Article

Biochemical changes during the reproductive cycle of the deep-sea decapod Nephrops norvegicus on the south coast of Portugal

December 2002
Marine Biology 141(6):1001-1009

December 2002
141(6):1001-1009

DOI:10.1007/s00227-002-0911-9

Authors:

Rui Rosa

University of Lisbon

Maria leonor Nunes

Instituto Português do Mar e da Atmosfera

The objectives of the present study were to characterize the changes in the proximate chemical composition, lipid classes, fatty-acid profiles, glycogen and cholesterol contents of the muscle, ovary and hepatopancreas of Nephrops norvegicus (L.), during the reproduction cycle of this species. The gonadosomatic index increased significantly in May and June and during maturation, suggesting that spawning may start in late spring or summer. The hepatosomatic index also increased throughout the ovarian maturation, suggesting that the hepatopancreatic resources are not depleted. Positive correlations between lipid levels in the ovary and the gonadosomatic index (r=0.51, P<0.05) and the hepatopsomatic index (r=0.27, P<0.05) were found. In fact, ovarian lipid levels increased with maturation, but no concomitant decrease occurred in hepatopancreatic lipids. The muscle showed very low lipid levels (mainly polar lipids), presenting a significant increase during May and June (P<0.05). Higher proportions of neutral lipids, mainly triacylglycerols, were observed in the ovary and the hepatopancreas. Since both ovarian and hepatopancreatic cholesterol increased with maturation, the mobilization of hepatopancreatic cholesterol stores to build up ovarian cholesterol was not clear. On the other hand, protein and glycogen contents in the muscle, ovary and hepatopancreas did not vary as a function of ovary maturity stage. Among the various tissues analysed, the glycogen was mainly stored in the hepatopancreas and to a lesser extent in the muscle. In both ovary and hepatopancreas the major fatty acids were 16:0, 18:1(n-7), 18:1(n-9), 20:5(n-3) and 22:6(n-3), and significant increases (P<0.05) in the levels of monounsaturated and polyunsaturated fatty acids were observed in the ovary during sexual maturation, which indicates these compounds are the major sources of energy during embryonic and early larval development. It was evident that reproduction has profound effects upon the biochemistry of this species, because there are large associated energy costs, owing to the increase in biosynthetic work, which will support the lecithotrophic strategy of the embryos and first larval stages.

Reproductive biology and biochemical changes in female mantis shrimp Oratosquilla oratoria (Stomatopoda) with ovary development from the Tianjin coastal zone of Bohai Bay

Article

Mar 2021
AQUACULTURE

Overexploitation and preliminary artificial breeding have led to an increasing interest in studying the reproductive biology and biochemical changes during gonad development in Oratosquilla oratoria. In this study, we established an accurate one-to-one correspondence between physical (and ovarian) morphology and ovarian histology during different maturity stages and improved the understanding of trophic dynamics with the progress of maturation, which will aid the aquaculture and artificial breeding techniques for this commercially important species. Based on ovarian histology and morphology, the ovaries were differentiated into six developmental stages, with five changes in color: immature stage (black), previtellogenesis (black), primary vitellogenesis (faint yellow), secondary vitellogenesis (golden yellow), maturation (light orange) and spent stage (brownish yellow). The visible colors of the median triangular structure of the telson can be used as an external morphological indicator of ovarian development status, and indicates that the females are near-ripe broods stocks when median triangular structure is almost filled with yellow. The gonadosomatic index (GSI) showed a statistically significant inverse correlation with the hepatopancreatic index (HPI) and muscle-somatic index (MSI). GSI significantly increased until stage III and HPI significantly decreased at stage II and recovered slowly thereafter. Nevertheless the MSI increased during the first two stages and decreased thereafter. A continuous decline in feeding intensity of females with ovarian development was found. The protein level in the muscle and hepatopancreas increased with protein accumulation in the ovary. Ovarian lipid concentration continued to increase, while, as in the hepatopancreas and muscle, lipid content decreased significantly at stage II and then recovered rapidly, followed by a sharp decline. Glycogen concentrations in the ovary kept steady, while in the hepatopancreas and muscle, there was a downward trend after a rise to the highest value. In conclusion, the energy for supporting ovarian development inevitably relies on energy reserves in the hepatopancreas and muscle and attention should be given to how to promote the transfer of organic reserves and energy to the ovaries during stock culture.

Biochemical composition of the hemolymph, hepatopancreas, ovary, and muscle during ovarian maturation in the penaeid shrimps Fenneropenaeus merguiensis and F. penicillatus (Crustacea: Decapoda)

Article

Jan 2013

The present study quantifies the concentrations of proteins, carbohydrates, and lipids in the hemolymph, ovary, hepatopancreas, and muscle of Fenneropenaeus merguiensis and F. penicillatus during ovarian maturation. Proteins were the major constituent in the hemolymph and ovaries of the 2 species, while lipids were the major constituent in the hepatopancreas. The protein, carbohydrate, and lipid contents in the ovaries of both species increased as ovaries matured. The increase in the protein, carbohydrate, and lipid contents in the ovaries during maturation indicates that the ovaries utilize these constituents to mature. Concentrations of lipids in the hepatopancreas decreased with ovarian maturation in both species. It appears that the lipid demands of ovarian maturation are met by the hepatopancreas reserves, as lipid decrease in the hepatopancreas coincided with an increase in fully mature ovaries. The increase of protein, lipid, and carbohydrate contents in the hemolymph with ovarian maturation in both species shows that the hemolymph serves as a vehicle for the mobilization of organic reserves. Proteins, carbohydrates, and lipids in the muscles of the 2 species did not seem to be related to ovarian maturation. In the present study, both the gonadosomatic index and the hepatopancreatic index also increased with ovarian maturation in F. merguiensis and F. penicillatus.

Biochemical changes during vitellogenesis in the red claw crayfish, Cherax quadricarinatus (von Martens)

Article

Mar 2010
AQUACULTURE

Redclaw crayfish (Cherax quadricarinatus) females at different stages of vitellogenesis were sampled to investigate variations in soluble protein, lipid and water content and in the amino acid and fatty acid composition of the hepatopancreas and ovaries. During vitellogenesis, the changes in the content of soluble proteins and lipids in the hepatopancreas and ovaries were dependent on both diet and the reserves from the hepatopancreas. However, in comparison to the ovary, the fluctuation of the amino acid composition in the hepatopancreas suggested that the protein resources mobilized from this organ was compensating for those gained from feeding. Changes in the fatty acid composition of the hepatopancreas showed limited compensatory function as for the quick accumulation of lipids in the ovaries. The proportional amounts of saturated fatty acids/mono-unsaturated fatty acids/poly-unsaturated fatty acids (PUFA) and the predominant fatty acids in both tissues indicated that the mobilization and utilization of fatty acids in freshwater species are different from that in marine species. Based on the redclaw's feeding habits, the commercial pellets used in this study may not be optimal, and a diet with less PUFA may suffice for its vitellogenesis and reduce the feeding costs.

Seasonal variations in the feeding ecology of Nephrops norvegicus in the Adriatic Sea: insights from stomach contents and stable isotope analyses

Article

Aug 2022

Norway lobster Nephrops norvegicus is one of the most important commercial species in the Mediterranean. This study focused on its feeding ecology in an important fishing ground within the Adriatic Sea, using an integrated approach of stomach content (SCA) and stable isotope (SIA) analyses. The simultaneous use of these tools represents a modern and complete approach that provides reliable data over time and reflects the feeding strategy of the analysed species. Monthly sampling was carried out (January-December 2019, July and October 2020; 589 specimens) to investigate seasonal changes in diet and trophic level. Variations in fullness, gonadosomatic and hepatosomatic indices were analysed to explore changes in feeding and variations in energy requirements linked to reproductive needs. Results showed that N. norvegicus mostly prey on decapod crustaceans and fish. Seasonal variations in prey consumption were likely linked to the reproductive patterns of the species. SIA results confirmed SCA findings and placed N. norvegicus at a high position within the benthic food web. Overall, considering that the Adriatic Sea represents one of the most important and productive fishing areas for Norway lobster, this study provides critical information for an effective ecosystem approach to fisheries management of this resource.

Ovarian development in swimming crabs: Comparative histochemistry and ultrastructure of Callinectes ornatus and Arenaeus cribrarius (Brachyura, Portunidae)

Article

Jun 2020
TISSUE CELL

The ovarian development of Callinectes ornatus and Arenaeus cribrarius was described using histochemistry and ultrastructure. Both species shows the same ovarian stages, which are the juvenile (JUV), adult rudimentary (RUD), developing (DEV), intermediary (INT), mature (MAT), and spent (OV) stages. The JUV and RUD stages showed similar characteristics, and previtellogenesis is characterized by meiotic prophase chromosomes. In the primary vitellogenesis, the oocyte cytoplasm shows many small and large cytoplasmic glycoprotein vesicles. These vesicles correspond to the dilated cisternae of the rough endoplasmic reticulum (RER), which produces the immature (endogenous) yolk. Secondary vitellogenesis (exogenous phase) begins at the DEV stage with the fusion of pinocytic vesicles and vesicles with immature yolks to form mature yolk granules. At the INT stage, the formation of the chorion begins, and the mature yolks increase in size and number, while the RER diminishes. In the MAT stage, the oocytes are completely formed, and the cytoplasm is filled with mature yolk, lipid droplets, and glycogen. There are no significant variations between the gonadosomatic and hepatosomatic indices, which allows us to infer that the transfer of reserves from the hepatopancreas is nearly constant during ovarian development, since we observed primiparous and multiparous females in the same sampled population.

A unified scale for female reproductive stages in the Norway lobster ( Nephrops norvegicus ): Evidence from macroscopic and microscopic characterization

Article

Dec 2018
J MORPHOL

Knowledge of the reproductive cycle in exploited species is important for a sustainable management of fisheries. Standardized scales to assess maturity stages are a fundamental tool to understand the demographic composition of exploited populations. Staging scales for female Norway lobster, Nephrops norvegicus, have been subject to a series of changes, and multiple inconsistent scales are in use in different fisheries regions. A unified, evidence‐based scale has not previously been established. We reviewed previous staging scales for the female ovary maturation and propose a revised scale based on the correlation between macroscopic and microscopic ovary characteristics. To provide better‐informed tools for future stock assessment, female stages were characterized through external observation on ovary color and size, and the progress of vitellogenesis. This study clarifies several biological phases that were conflated in previous scales. First, we demonstrate how to distinguish between immature ovaries in juvenile females (Stage 0) versus the earliest ovary maturation stage in adults. Second, the new scale differentiates between “mottled” ovaries seen in two separate biological stages: the spent ovaries that undergo partial resorption in berried females, versus ovaries of females which failed to spawn and undergo full resorption. To ensure consistent application, colors are assessed relative to international standards (RAL/Pantone). This new, practical staging scheme clarifies the correlation between microscopic characteristics and macroscopically observable details in ovary maturation. Adoption of this unified staging scale will improve maturity analyses, help to identify stocks with potentially reduced reproductive capacity, and facilitate broad‐scale comparisons.

Chemical composition of the freshwater prawn Cryphiops caementarius (Molina, 1782) (Decapoda: Palaemonidae) in two populations in northern Chile: Reproductive and environmental considerations

Article

Full-text available

Sep 2015

Reductions of its natural populations have led to recent efforts in small-scale aquaculture of the freshwater prawn Cryphiops caementarius, either for conservation or commercial purposes. However, the lack of knowledge about its nutritional requirements has been one of the major obstacles for its successful culture. Given its importance, this study determines and compares the chemical composition (moisture, ash, crude protein, total lipids and nitrogen free extract) of whole animals and main storage tissues (gonad, hepatopancreas and muscle), of C. caementarius adult prawns from two natural populations. Moreover, the relation of this composition with reproductive and environmental parameters (sex, maturation and habitat) is discussed. The specimens were collected in Limarí and Choapa rivers (Coquimbo, Chile) during reproductive season, and divided into six categories according to capture location, gonad maturation stage, and gender. The chemical composition of whole animals and storage tissues was compared among categories. Significant differences were observed between tissues, sexes, maturity stages and locations. Regarding tissues, the muscle and the gonads were rich in protein, whereas the hepatopancreas had high lipid content. According to results, factors such as sex, habitat and stage of gonad maturation can modify the biochemistry of C. caementarius. Nonetheless, the main chemical variations were observed in tissues involved in regulatory processes (hepatopancreas and gonads), and to a lesser extent in structural tissues (muscle). This is the first study known that reports information about the biochemistry of C. caementarius and its findings may be useful to improve feeding practices in aquaculture.

Dinâmica do desenvolvimento gonadal de Aegla platensis Schmitt (Decapoda, Anomura, Aeglidae)

Article

Full-text available

Jan 2007

The effects of seasonal variation on the nutritional condition of Nephrops norvegicus (Astacidea: Nephropidae) from wild populations in the western Mediterranean

Article

Full-text available

Jun 2014

The Norway lobster, Nephrops norvegicus is a target fishery species in European waters. The stock assessment of N. norvegicus is complicated because it is caught in commercial gear only when it emerges from its burrow. Landings are lower in winter, and feeding limitations have been hypothesized as the cause. Wild large-sized male lobsters were sampled each season (winter, spring, summer and autumn), and two groups of animals were kept in captivity for 90 d (fed and fooddeprived). The hepatopancreas and muscle were dissected, weighted, frozen for biochemical analyses (proximal analyses and DNA/RNA) and fixed in Bouin solution for microscopic observations. The oxygen consumption rates in the wild individuals caught in the spring and in the captive animals after the treatments were measured. Significant differences among the experimental groups were observed in the lipid concentration of the hepatopancreas and muscle, the water content in the hepatopancreas, and the numbers of vacuoles and pyknotic nuclei in the cells of the tubules of the hepatopancreas. The results showed that the wild Norway lobsters generally presented intermediate values between those observed in the fooddeprived and the fed lobsters kept in captivity, but the values were closer to those obtained for the fed animals. This finding indicates that the wild animals exhibit a good nutritional condition throughout the year. Therefore, the wild males of N. norvegicus do not face food deprivation during winter as is suggested by the pattern of commercial catches, the flow of organic matter, and the moulting period/reproductive behaviour of the species.

Dynamics of gonadal development of Aegla platensis Schmitt (Decapoda, Anomura, Aeglidae)

Article

Full-text available

Dec 2006
REV BRAS ZOOL

One way to estimate gonadal development through the reproductive cycle is to observe the growth of the gonads related to the organs used to store energy. The aim of this study was to follow the gonadosomatic and hepatosomatic indexes during annual cycle of Aegla platensis Schmitt, 1942. Adult animals were collected in Taquara, Rio Grande do Sul, Brazil (29°46'S, 50°53'W). Males and females were initially weighed and dissected and had their gonads and hepatopancreas (HP) removed and weighed in order to estimate the Gonadosomatic (GI) and hepatosomatic (HI) indexes. In females, the indexes were also compared to the degree of development of the ovaries. In males the GI showed a peak of gonadal development in the autumn (p < 0.05), just when the HI showed a decrease (p < 0.05). Females showed a rise in the GI at the end of summer and beginning of autumn (p < 0.05). In females, GI values increased as the ovary matured. In A. platensis, for both males and females, the HI never showed values lower than the GI, which may indicate that these aeglids show a different pattern of energy utilization from other decapods, where as gonadal development peaks the HI decreases markedly.

Inter-individual and within brood variability in the fatty acid profiles of Norway lobster, Nephrops norvegicus (L.) embryos

Article

Full-text available

Dec 2011
MAR BIOL

The present study investigated the existence of inter-individual and within-brood variability in the fatty acid (FA) profile of developing embryos of Nephrops norvegicus. In all surveyed females (n = 5), the quantitatively most important FAs were as follows: 22:6n-3 (20.8 ± 3.9% average of total FA ± standard error), 18:1n-9 (19.5 ± 2.0%), 16:0 (15.2 ± 3.4%), 20:5n-3 (10.2 ± 1.4%), 16:1n-7 (8.9 ± 1.6%), and 18:1n-7 (5.7 ± 1.3%). Differences in FA profiles of embryos in the same clutch were assessed using brooding chamber side (left and right) and pleopod (1st and 2nd, 3rd and 4th, and 5th) as predictive factors. There were no significant differences in the FA composition of embryos sampled from both sides of the brooding chamber in 4 of the 5 surveyed females. However, all females exhibited significant differences in the FA profiles of embryos sampled from different pleopods. Both saturated FA (SFA) and highly unsaturated FA (HUFA) present in developing embryos exhibited marked differences along the breeding chamber. Overall, FA reserves appeared to vary significantly within broods, which can ultimately be reflected on early larval survival. A potential cause for the within-brood variation recorded in the FA profile of developing embryos include (1) differential female investment during ovarian maturation, mainly due to variation in food quality/availability; (2) differential lipid catabolism during the incubation period of developing embryos, as a consequence of embryos position within the female’s brooding chamber; or (3) differential female investment during ovarian maturation amplified by differential lipid catabolism during the incubation period.

Temporal variations in fatty acid composition of deep-sea holothurians: Evidence of bentho-pelagic coupling

Article

Full-text available

Jan 2004
MAR ECOL-PROG SER

Fatty acid biomarkers were used to examine the diet of deep-sea holothurians. We collected 3 species from the Porcupine Seabight and Porcupine Abyssal Plain, NE Atlantic, between 800 and 4850 m in August 2001 (summer), March 2002 (pre-spring bloom), and October 2002 (autumn). Of these, 2 species, the abyssal Amperima rosea and the bathyal Bathyplotes natans, showed significant variations in fatty acid compositions. These are likely to be seasonal. Polyunsaturated fatty acids (PUFAs) were dominant within muscle tissue of both species during August 2001 and October 2002, in particular 20:4 (n-6), 20:5 (n-3) and 22:6 (n-3). During March 2002, prior to the spring bloom, there were substantially lower proportions of PUFAs in both species, and increased amounts of mono-unsaturated fatty acids (monoenes), particularly the bacterially-derived biomarkers 18:1 (n-7) and non-methyl uninterrupted dienes (NMIDs). In contrast, the fatty acid composition of the third species, the abyssal Deima validum, remained relatively stable, with muscle tissue containing a high proportion of PUFAs during pre- and post-spring-bloom periods. A further 6 species were sampled in March 2002 and October 2002. Across all these species, 3 patterns of fatty composition were evident: (1) Laetmogone violacea had higher proportions of PUFAs in October than in March; (2) Psychropotes longicauda and Benthogone rosea had lower proportions of PUFAs in October than in March; (3) Deima validum, Oneirophanta mutabilis, Paroriza pallens and P. prouhoi had unchanged fatty acid compositions during these contrasting periods. These differences may be related to the varying reproductive strategies of the species. The implications of changes in fatty acids for reproductive processes, and how these could be factors determining allocation of lipid resources in gonads, is discussed.

Temporal fatty acid dynamics of the octocoral Veretillum cynomorium

Article

Nov 2011

The objectives of the present work were to investigate the temporal variation in the fatty acid (FA) composition of the octocoral Veretillum cynomorium, examine the effects of reproduction and environmental factors on FA variation, and establish a chemotaxonomic identification for this species. Mean oocyte size-frequency distributions showed that the majority of the oocytes had an intermediate size (Group II) before spawning (April and June). The late-vitellogenic oocytes (Group III) became absent in August and October and, during this post-spawning period, oocytes were primarily of small size (Group I). Most of the major FA, 16:0, 18:0, 20:4n-6, 20:5n-3, and the tetracosapolyenoic fatty acid (TPA), 24:6n-3, varied significantly throughout the year (p<0.01), with two peaks in August/October and February. The boost in early oogenesis, also associated with warmer temperatures, seemed to be responsible for the observed increase in FA content between June and August. The highest values of FA content were observed in February when intermediate oogenesis (Group II) was at its peak and there were considerable levels of available food in the environment. Also, the increase in food availability seemed to trigger the final stages of gametogenesis. The high quantity of 18:1n-7, odd-numbered and branched FAs, suggested the presence of a dynamic bacterial community in V. cynomorium, probably as an adaptive response to the lack of symbiotic microalgae. Although the presence of TPAs is the main feature distinguishing octocorals from other coral species, here we showed that there was no single FA clearly dominating the FA composition of V. cynomorium throughout the year. Instead, four main FAs share similar concentrations: 16:0, 20:4n-6, 20:5n-3 and 24:6n-3. The predominance of these four FAs combined with the higher amount of 24:6n-3 when compared to 24:5n-6 may serve as a chemotaxonomic feature to distinguish this octocoral species (or genus).

Biochemical Composition of Eggs, Larvae and Tissues of Macrobrachium tenellum Females Fed Diets with Different Lipid and Protein Levels

Article

Full-text available

Apr 2024

One way to approach the nutritional requirements of native shrimp, necessary to consolidate their culture, is to know their biochemical composition. The effect of feeding two levels of lipids (4 and 12% L) and four levels of proteins (30, 35, 40 and 45% P) in M. tenellum females was evaluated with respect to the biochemical composition of their eggs (EG), larvae (LR), gonad (GO) and hepatopancreas (HP). Total protein (TP), total carbohydrate (TC) and total lipid (TL) were estimated. In EG, L and P levels influence TP and TL; TP increases in diets higher than P35. In LR, there are no differences (p > 0.05) in TP and in TL, only diets L4P40 and L12P30 were different (p < 0.05). In GO, there is no trend in TP differences; in TC there was variation in the range of the data and TL was higher in L4P30 and L4P35. In HP, the diets with L4 obtained the highest TP values (p < 0.05); the L12 diets were higher in TL (p < 0.05). In general, diets with an inclusion of L12 showed the highest TP, TC and TL means, within this lipid level the P30 diet stood out; therefore, it is recommended to use a diet with L12P30 in the formulation of balanced feed for the species. Key Contribution: Different levels of lipids and proteins in diets affect the biochemical composition of eggs, larvae and tissues of M. tenellum. The diet with 12% lipids and 30% proteins obtained the best results.

Insight of vitellogenesis patterns: A comparative analysis of the differences between the primary and secondary vitellogenesis period in the ovary, hepatopancreas, and muscle of mud crab, scylla paramamosain

Article

Full-text available

Aug 2022

The mud crab, Scylla paramamosain, has abundant nutrients in its edible parts, ovary, hepatopancreas, and muscle during the ovarian maturation stage. The ovary of S. paramamosain can re-mature after spawning during the secondary ovarian maturation period. We aimed to analyze the characteristics of the first vitellogenesis period (FVP) ¹ and second vitellogenesis period (SVP) ² of S. paramamosain during ovarian maturation to understand the differences in vitellogenesis patterns between the first and second ovarian maturation periods. Accordingly, the gonadosomatic index (GSI) and hepatopancreatic index (HSI), the external and histological characteristics of the ovary and hepatopancreas, the Sp-Vg (vitellogenin, Vg) expression levels in the hepatopancreas and ovary, and the dynamics of the biochemical components in the ovary, hepatopancreas, and muscle were determined. Based on the results, the GSI was significantly positively correlated with HSI during the FVP and significantly negatively correlated with HSI from stage Ⅳ to stage Ⅴ of the SVP. A significant difference was found between the FVP and SVP in the hepatopancreas. Notably, the hepatopancreas displayed a gradual degeneration trend during the SVP. The expression level of Sp-Vg was significantly higher in the hepatopancreas than that in the ovary during the FVP and SVP. Seventeen amino acids were detected in the hepatopancreas, ovary, and muscle during the FVP and SVP, with glutamate as the predominant amino acid. During the FVP and SVP, the C16:0 and C18:1n9c were the dominant fatty acids in the hepatopancreas and ovary, the MUFA gradually increased in the ovary and hepatopancreas, and a significant difference was found in the dynamic trend of the HUFA and SFA contents from stage Ⅳ to stage Ⅴ between the FVP and SVP. These findings indicate that the ovary can re-mature after spawning in S. paramamosain and can maintain the status of the first ovarian maturation; however, the hepatopancreas gradually degenerate during the SVP.

Fatty Acid Composition in the Hepatopancreas of the Barents Sea Red King Crab

Article

Jul 2020

Development of enzymes during ontogeny of two freshwater Decapoda: Aegla uruguayana (Aeglidae) and Macrobrachium borellii (Palaemonidae)

Article

Full-text available

Oct 2018

The similarities or differences among species of the same family or among different families suggest a relationship with their feeding habits or a preference for the various types of food. The aim of this study was to identify the presence of digestive enzymes lipases, total protease, amylases and cellulose, and the effects of sex and size in these activities in two decapod freshwater crustaceans. Specimens of different sizes and sexes of Aegla uruguayana and Macrobrachium borellii were collected in the natural environment. In laboratory, enzymatic preparation consisted in homogenising the digestive gland in a buffer Tris‐HCl. The homogenates were centrifuged and the lipid layer was removed. Enzyme activities were determined using standard protocols. There were no statistically significant differences between sexes in any of the species under study. However, there were changes in the activity of amylases during the ontogeny of A. uruguayana, indicating that in juveniles the values of said activity are significantly higher than in the rest of the groups. M. borellii showed ontogenetic differences in total proteinase activity: organisms of range 2 (intermediate sizes) presented enzymatic activities much smaller than organisms of range 4 (larger sizes). The comparisons of enzymatic activities between both species yielded significant differences, being higher the values in the species A. uruguayana with respect to M. borellii. The results obtained in this work indicate that although both species are omnivorous and consume similar items, the activity of these digestive enzymes could be an evidence of different strategies of utilisation of the resource.

Insights Into Sexual Maturation and Reproduction in the Norway Lobster (Nephrops norvegicus) via in silico Prediction and Characterization of Neuropeptides and G Protein-coupled Receptors

Article

Full-text available

Jul 2018

Multiple biological processes across development and reproduction are modulated by neuropeptides that are predominantly produced and secreted from an animal's central nervous system. In the past few years, advancement of next-generation sequencing technologies has enabled large-scale prediction of putative neuropeptide genes in multiple non-model species, including commercially important decapod crustaceans. In contrast, knowledge of the G protein-coupled receptors (GPCRs), through which neuropeptides act on target cells, is still very limited. In the current study, we have used in silico transcriptome analysis to elucidate genes encoding neuropeptides and GPCRs in the Norway lobster (Nephrops norvegicus), which is one of the most valuable crustaceans in Europe. Fifty-seven neuropeptide precursor-encoding transcripts were detected, including phoenixin, a vertebrate neurohormone that has not been detected in any invertebrate species prior to this study. Neuropeptide gene expression analysis of immature and mature female N. norvegicus, revealed that some reproduction-related neuropeptides are almost exclusively expressed in immature females. In addition, a total of 223 GPCR-encoding transcripts were identified, of which 116 encode GPCR-A (Rhodopsin), 44 encode GPCR-B (Secretin) and 63 encode other GPCRs. Our findings increase the molecular toolbox of neural signaling components in N. norvegicus, allowing for further advances in the fisheries/larvae culture of this species.

Energy reserves in the water louse Asellus aquaticus (Isopoda, Crustacea) from surface and cave populations: Seasonal and spatial dynamics

Article

Full-text available

Jul 2018
FUND APPL LIMNOL

The depletion of energy reserves in animals has already been recognized as a useful indicator of environmental pollution with potentially high ecological significance. However, apart from being affected by pollution, energy reserves in organisms also vary depending on natural abiotic and biotic factors. Seasonal and spatial dynamics of energy reserves in Asellus aquaticus (Isopoda, Crustacea) are presented here to determine the reference values of energy biomarkers. A. aquaticus are abundant and ubiquitous freshwater crustaceans and, as such, very suitable organisms for biomonitoring. Individuals were collected in spring, summer and autumn at two surface localities and one cave locality along the sinking river Pivka (Slovenia), and analysed for lipid, carbohydrate and protein content. The obtained values of energy reserves are discussed together with the physical and chemical parameters of water determined at the time of sampling. The surface-water populations in particular show a seasonal and spatial variability of energy reserves. Carbohydrates follow a distinct seasonal pattern of decreasing values toward autumn in all three populations. The spring protein content in both surface populations is much lower compared with the summer and autumn levels, while no distinct pattern was observed for lipids. The quantity of energy reserves in cave specimens does not differ much from the surface ones, but are less variable. Our data reveal that energy biomarkers differ between both season and locality, which should be taken into consideration in biomonitoring studies. We also suggest the use of only male specimens of comparable size where possible. To enable a valid comparison between different studies, the methods for the analysis of energy reserves should be harmonised. © 2018 E. Schweizerbart'sche Verlagsbuchhandlung, Stuttgart, Germany

A baseline study of the metallothioneins content in digestive gland of the Norway lobster Nephrops norvegicus from Northern Adriatic Sea: Body size, season, gender and metal specific variability

Article

Jun 2018
MAR POLLUT BULL

Abstract Metallothioneins content was investigated in digestive gland of two wild-caught Norway lobster Nephrops norvegicus populations from the Northern Adriatic Sea, in relation to body size, season and gender. Concomitant accumulation of cadmium, mercury, arsenic, lead, chromium and manganese, reactive oxygen species concentration and energy reserves in digestive gland were also assessed. While differences between genders were not recorded, metallothioneins content seasonal trends were affected by body size. Most of parameters displayed inconsistent trends across sampling sites. Significant correlation between metallothioneins content and cadmium, arsenic and mercury concentrations was recorded only for larger lobsters. A negative correlation of reactive oxygen species concentration and metallothioneins content was observed for small, but not large lobsters. Energy reserves, in particular lipids, could considerably influence biochemical and chemical parameters variations. The present results constitute the essential baseline for future studies aimed at evaluating the N. norvegicus health in relation to metal contamination of coastal sediments.

Evaluation of genes involved in Norway lobster (Nephrops norvegicus) female sexual maturation using transcriptomic analysis

Article

Full-text available

Dec 2018
HYDROBIOLOGIA

The Norway lobster Nephrops norvegicus is the most important commercial crustacean species in Europe. Recent decline in wild captures and a reduction in total abundance and size at first maturation indicate that the species is overexploited. Increasing knowledge of its reproduction, specifically at the molecular level will be mandatory to improving fisheries management. The current study investigated differences between immature and mature N. norvegicus females using Next Generation Sequencing technology applied to multiple tissues. Ovarian maturation-related differential expression patterns were observed for 4362 transcripts in ovary, hepatopancreas, eyestalk, brain, and thoracic ganglia in N. norvegicus. Transcripts detected in the study include vitellogenin, crustacean hyperglycaemic hormone, retinoid X receptor, heat shock protein 90 and proteins encoding lipid and carbohydrate metabolizing enzymes. From the study, data were collected that can prove valuable in developing more comprehensive knowledge of the reproductive system in this lobster species during the ovarian maturation process. Additional studies will be required, however, to identify potential novel genes and to develop a molecular toolkit for crustacean species that can be applied to improving sustainable future production.

ECOLOGÍA TRÓFICA Y ENERGÉTICA DEL CANGREJO DE MANGLE Aratus pisonii (CRUSTACEA: BRACHYURA: GRAPSIDAE) (H. MILNE EDWARDS)

Thesis

Full-text available

Jul 2010

Beatriz López Sánchez

Aratus pisonii (H. Milne Edwards, 1837) is one of the most common crustaceans in American mangroves. Certain features of their life history and population dynamics, such as size and percentage of mature females have been correlated with the structural development of mangroves. In particular, it has been documented that the size of crabs increases progressively from less developed mangroves located in hypersaline lagoons, to a maximum in mangroves at the mouths of rivers with greater structural development. The aim of this study was to investigate whether a structural gradient of mangroves leads to a variation in energetic condition and food resources used and assimilated by A. pisonii and also to assess possible variations between periods of drought and rain. The results show that the quality of the body reserves varied along the structural gradient of mangroves, suggesting the consumption of resources with diverging nutritional quality. There was an increase in the level of body reserves in hypersaline habitats with lower structural development during the dry season. The variables that described the structure of mangroves (basal area, height of mangroves) were more important than the nutritional characteristics of the leaves (Nfoliar, polyphenols), in explaining the variation in the level and quality of body reserves and gonads of this crab along the mangrove gradient. The crabs in the estuarine mangrove, the habitat with the highest structural development within the gradient evaluated, exhibited low levels of body reserves. The body stores as expressed by the C / N of the hepatopancreas, showed an increase to the habitats with higher salinity and lower structural development. The same trend was observed in nitrogen levels in skeletal muscle. Have been reported the largest body sizes of these crabs in the mangrove estuary, as well as the maximum percentage of mature females and a continuous and balanced reproduction throughout the year. It is proposed that estuarine mangrove crabs are constantly compensating for the metabolic requirements, without having to store body reserves, therefore, are directing energy to both, growth and reproduction throughout the year. The results of the analysis of stomach contents showed that in the mangrove estuary was high availability of resources in both seasons of the year, suggesting that these crabs have enough resource, which coincides with a lower storage of body reserves. The body condition of crabs decreased to less structural development mangrove with hypersaline condition, in line with a foliar resource of lower quality in these environments. Populations of A. pisonii of hypersaline environments with lower structural development seem to rely heavily on stored reserves during the drought, to achieve reproductive success in the rainy season. The storage of body reserves would be necessary for crabs in these habitats with seasonal reproduction, gather the necessary energy and achieve reproductive success. It was shown that populations of crabs that inhabit the mangroves of lower structural development (stunted) and hyper salinity conditions are limited by the resource. A trade-off was observed between the energy directed to growth and reproduction in stunted mangrove. This was confirmed by the inverse relationship observed between the energy directed to growth and reproduction. Cannibalistic behavior occurred with greater intensity in these crabs, supports the limitation of resources of these populations. In addition, these crabs have the lowest nitrogen content of muscle and lower body sizes. Stable isotope analysis showed that with decreasing the structural development of the mangroves and increasing salinity, the crabs exhibited a greater assimilation of the fraction of C and N from insects. It is likely that the crab body condition influencing the selection of the resource, especially during the drought in the hypersaline mangrove scrub, where cannibalism was detected. This behavior may be a consequence of the low quality of available resources in that habitat. Trophic relationships of A. pisonii change along the structural gradient of mangroves. In crabs living in more structural development mangrove was observed a greater assimilation of C and N of leaves. However towards the mangroves with intermediate structural development, Aratus populations behave as generalists, meaning that treated more equitably funding sources. These results contribute to a better understanding of the relationship “mangrove – crab” and extensive knowledge of the ecology of this species in the Americans mangrove.

Histological profile and fatty acid composition in hepatopancreas of blue swimming crab, Portunus pelagicus (Linnaeus, 1758) at different ovarian maturation stages

Article

Jan 2016

The study of the hepatopancreas structure is important to provide the morphological and molecular information for future research involving the nutrition requirements of Portunus pelagicus culture. Thus, the study of histological characteristics and fatty acid (FA) composition in hepatopancreas of different ovarian maturation stages of the P. pelagicus were investigated. There are five stages in ovarian maturation of P. pelagicus which are: Stage I (immature), Stage II (early maturing), Stage III (advance maturing), Stage IV (mature) and Stage V (spawned/re-maturation/spent stage). The histological study of hepatopancreas showed that the lumens of most of the tubules were irregular-like shape in Stage I, circle-like shape in Stage III and ovul-like shape in Stage IV. A total of 29 types of FA were found in the hepatopancreas of P. pelagicus. The most dominant FA was C16:0 (Palmitic acid) with concentration of 456.10±266.23 mg/g(38.73±4.12%) at stage II. Second most dominant FA was C18:0 (Stearic acid) with concentration of 203.99±120.28 mg/g (13.97±1.62%) at stage III and followed by C20:5n3 (Eicosapentanoic acid) with concentration of 131.19±84.70 mg/g (8.98±1.13%) at stage III. In conclusion, the tubules structure and FA concentration of hepatopancreas play an important role in reproduction and diet formulation for portunid crab broodstock. © Published by Central Fisheries Research Institute (CFRI) Trabzon, Turkey.

Growth and reproduction of the mangrove crab Goniopsis cruentata (Latreille, 1803) (Crustacea: Decapoda: Grapsidae) in southeastern Brazil

Article

Full-text available

Jun 2015

Goniopsis cruentata is a common semi-terrestrial crab in Brazilian mangroves and an important fishery resource for traditional communities in the northeastern Brazilian coast. Aiming to contribute to the knowledge about the species, this study evaluated the carapace width and weight growth curves, the relative growth of weight versus carapace width, and the temporal variation of gonadosomatic and hepatosomatic indices for the species. A total of 524 crabs were collected in a mangrove area of Ubatuba municipality, state of São Paulo. The growth-curves parameters and longevity (tmax) were estimated for males (CW∞=50.6 mm, WE=56.4 g, k=2.24, t0=0.003631502 year-1, tmax=1.3 years) and females (CW∞=50.7 mm, WE∞=58.8 g, k=2.50, t0=0.003247209 year-1, tmax=1.2 years). The age at onset of sexual maturity was 0.23 years for both genders. The weight-growth model was isometric for the immature developmental stages and allometric negative for adults. The species exhibited a continuous reproduction, with breeding peaks in spring and summer months. The weight dynamics of gonads and hepatopancreas were not clearly related. The growth and reproductive patterns indicated that Goniopsis cruentata has a life-history that prioritizes reproduction instead of survival. The species exhibited some of the highest growth rates and lowest longevity estimates reported for brachyuran species in Brazil.

Dynamics of gonadal development of Parastacus varicosus (Crustacea, Decapoda, Parastacidae)

Article

Full-text available

Dec 2006
IHERINGIA SER ZOOL

The level of gonadal development of a species can be evaluated by the determination of the gonadossomatic (GSI) and the hepatossomatic (HSP) indices. The hepatopancreas is the most important centre for storage of reserves in decapods, which can be transferred to the gonads during their development. The aim of this study was to estimate gonadal development of Parastacus varicosus Faxon, 1898 by means of macro and microscopic observations, as well by the inspection of the variations of gonadossomatic and hepatossomatic indices. The crayfishes were collected in the Gravataí hydrographic basin, Cova do Touro locality, State of Rio Grande do Sul, Brazil. Female's gonads were weighted for the recognition of the gonadossomatic index and histological analysis. Hepatopancreas weight was also obtained to determine the hepatossomatic index. The results showed a decrease of the hepatossomatic index and an increase of the gonadossomatic index in females during the seasonal transition period from spring to summer, suggesting a possible transfer of the hepatopancreatic reserves to the gonads during the reproductive period. However, considering that this decrease did not show significance at p>0.05 level, it is likely that other tissues contribute for this transfer, as hemolymph, for instance.

Contenido bioquímico del ovario y hepatopáncreas de Uca longisignalis y Uca nr. minax

Article

Full-text available

Sep 2006
SCI MAR

Biochemical composition of ovary and hepatopancreas tissues in wild populations of Uca longisignalis and Uca nr. minax were monitored during the reproductive season. Total lipid (concentration and content), C (carbon), N (nitrogen), and C:N ratios of the ovary and hepatopancreas were quantified over the course of ovarian maturation. Ovary lipid and C concentration varied significantly over the course of ovarian maturation for both species, but there was no relationship between lipid concentration or hepatopancreas content and the stage of ovarian development in females. Hepatopancreatic lipid and C concentration did not differ between sexes of U. nr. minax. Lipid demands of ovarian maturation thus appear to be met in large part by increased dietary intake and not purely by translocating lipid stores from the hepatopancreas. In both Uca longisignalis and U. nr. minax, the color of the hepatopancreas may be used as an indicator of the lipid and C levels of the hepatopancreas. Cadmium-yellow and lemon-yellow hepatopancreas tissues had the highest lipid concentrations. No evidence could be found to demonstrate depletion of lipid or C concentrations in the hepatopancreas concomitant with ovarian maturation.

Tissue composition and haemolymphatic metabolites during gonadal development in Aegla platensis (Crustacea, Decapoda) maintained in experimental culture

Article

Full-text available

Mar 2011

Georgina Bond-Buckup

Guendalina Turcato Oliveira, Cristina Hack, Mauricio Almerão, Georgina Bond-Buckup & Bibiana Kaiser Dutra. ABSTRACT: (Tissue composition and haemolymphatic metabolites during gonadal development in Aegla platensis (Crustacea, Decapoda) maintained in experimental culture). This study describes the variation of tissue composition and haemolymphatic metabolites in the anomuran crab A. platensis, which was maintained for 90, 120, 150, and 180 days under laboratory conditions, and relates the data collected to reproductive aspects of this species. Individuals were collected during the winter from Mineiro Creek, in Rio Grande do Sul, Brazil. Some of the individuals were killed when collected and the remaining animals were maintained in a laboratory for different time periods using a commercial diet. Haemolymph, hepatopancreas and gonads were removed at different times of cultivation to determine their biochemical composition using spectrophotometric methods. Hepatosomatic and gonadosomatic indexes were determined. Statistical analysis revealed significant differences between the sexes in all metabolites except in the proteins levels in the haemolymph. We observed an increase of ovigerous females kept under the same culture conditions between 120 and 150 days and we found an increase in the gonadosomatic index and a decrease in the hepatosomatic index in both sexes for the same times. Results showed that the regular food supply caused an increase in the gonadosomatic index in both sexes during all the time periods when compared to the results of animals from the natural environment. We also observed that the females used part of their hepatopancreatic reserves for vitellogenesis and gametogenesis, but the nutrients obtained from the other tissues and the diet were very important for supporting reproduction. Males used the metabolic reserves for growth, gametogenesis, and reproductive behaviors. This study indicates that reproductive events depend on a regular food supply. Keyword: Crustacea, Aeglidae, biochemical composition, Aegla platensis, diet, reproduction.

Lipid biomarkers reveal geographical differences in food supply to the cold-water coral Lophelia pertusa (Scleractinia)

Article

Full-text available

Dec 2009

Despite its importance as an ecological engineer, little is known about the feeding ecology of the widespread reef framework-forming cold-water coral Lophelia pertusa. This is the first study to compare lipid signatures of L. pertusa from different areas in the North Atlantic using samples from 2 sites in the eastern Atlantic and 2 seamounts in the western Atlantic. Lipid samples were collected in February, May, July and November from the Mingulay reef complex off western Scotland, but no clear seasonal pattern was observed. High lipid content and large wax ester fractions were recorded from all sites, with the highest values recorded at the shallowest site (Mingulay). Here the prevalence of copepod lipid biomarkers-monounsaturated fatty acids 20: 1 (n-9) and 22:1 (n-11) and their fatty alcohols-indicates L. pertusa feeds predominantly on calanoid copepods. At deeper offshore sites, the abundance of the fatty acid 18:1(n-9) and fatty alcohol 16:0 suggest a significant dietary input from non-calanoid copepods. Our results imply that the shallow Mingulay site is likely to receive a greater input of fresh surficial material and a higher abundance of herbivorous calanoid copepods, while at the deeper sites, carnivorous or omnivorous non-calanoid copepods are likely to be more abundant. L. pertusa therefore appears to be an opportunistic feeder capable of taking a variety of zooplankton prey. Further investigation is required to assess site-specific dependence on prey sources.

Variable within-brood maternal provisioning in newly extruded embryos of Homarus gammarus

Article

Full-text available

Apr 2013

Offspring quality of decapod crustaceans has been widely studied, with special emphasis on the sources of variability determining embryonic and larval quality. Nevertheless, maternal provisioning has commonly been overlooked as a potential source of offspring within-brood variability. In the present study, the existence of variable maternal provisioning was assessed through the analysis of the fatty acid (FA) profile of newly extruded embryos from different regions of the brooding chamber of Homarus gammarus. Significant differences in the FA profile of embryos sampled from different pleopods and sides of the brooding chamber were recorded. Significant deviations of the overall mean of each surveyed female were also observed for essential FA, particularly 20:4n-6, 20:5n-3 and 22:6n-3. Lipid energy available to fuel embryogenesis also varied among embryos sampled from different regions of the brooding chamber. Results suggest variable female investment at oocyte production, which may be amplified during the incubation period of developing embryos by differential lipid catabolism. For the first time, maternal provisioning is evidenced as an additional source for within-brood variability in the FA profile of embryos.

Muscle and exoskeleton extracts analysis of both fresh and marine crustaceans Procambarus clarkii and Erugosquilla massavensis

Article

Full-text available

Nov 2011
AFR J PHARM PHARMACO

Salwa A H Hamdi

Both fresh and marine edible crustaceans Procambarus clarkii and Erugosquilla massavensis, respectively, are now important components of our local aquatic fauna in Egypt that have a small yet growing economic importance in our markets. So, the purpose of the present work was, therefore, to assess the protein, amino acids, fatty acids, minerals, vitamins, protein electrophoresis and dendrogram analysis of their extracts for the first time in Egypt which may be in the future play an important role in some pharmaceutical industries and may be used as a specific health foods (functional supplement). In the present study, nutritional analysis of muscle and exoskeleton extracts of P. clarkii and E. massavensis indicated the presence of a high amount of protein, 9 essential amino acids and 9 non essential amino acids including taurine which has a very scientifical action and benefit for men. Also, the results showed the presence of 9 unsaturated fatty acids which included essential fatty acids linoleic acid (Omega 6) and alpha linolenic acid (Omega 3) which have many functions for man (food supplement) in addition to 4 saturated fatty acids. The minerals recorded were Cu, Zn, Mn, Fe, Mg, Ca, K and P and the vitamins were Vitamims A, D, E, B 1 , B 2 , Bp, B 6 and B 12 . From the electrophoretic analysis of protein, the dendrogram analysis showed the highest similarity between the muscle and exoskeleton extracts of P. clarkii.

Seasonal changes in nucleic acids, amino acids and protein content in juvenile Norway lobster ( Nephrops norvegicus)

Article

Sep 2003

The objective of this study was to describe the seasonal variations in nucleic acid contents and amino acid profiles in the muscle of juvenile Nephrops norvegicus. RNA and protein contents, and RNA:protein and RNA:DNA ratios varied significantly between seasons, being highest in spring and lowest in autumn/ winter (P < 0.05). Though DNA content increased significantly from autumn to summer (P < 0.05), protein:DNA ratio did not show significant seasonal variations (P>0.05). In respect to protein-bound amino acid content (BAA), a significant increase was observed from winter to summer (P < 0.05). Both essential (EAA) and non-essential amino acids (NEAA) increased significantly (27.6% and 27.8%, respectively; P < 0.05), mainly due to the considerable increase in arginine and proline (59.1% and 225.2%, respectively; P < 0 .05). A significant decrease was observed in the free amino acid content (FAA) from winter to summer (P < 0.05); and a higher percentage decrease occurred in free non-essential (FNEAA; 27.9%) in comparison to free essential amino acids (FEAA; 21.8%). The significant increase in RNA and BAA contents from winter to spring may be related to protein synthesis. On the other hand, the lowest values obtained in winter may be due to a reduction in feeding activity; in this period the muscle protein must be progressively hydrolysed, which is evident with the higher FAA content. The liberated amino acids enter the FAA pool and become available for energy production.

The dual functions of sea urchin gonads are reflected in the temporal variations of their biochemistry

Article

Feb 2006

Fatty acid analyses are emerging as a powerful technique to probe trophic interactions between organisms. In this paper, the application of both this procedure and gonad index (GI) determination on two populations (intertidal and subtidal) of the echinoid Psammechinus miliaris is reported. The investigation spanned the 3-month spawning period of Scottish west coast populations. In both populations a progressive decrease in the GI was found, coupled with an increasing maturity stage (from mature to spent). Sexual maturation and decrease in GI was synchronous between the two populations. In conjunction, there were distinct changes in gonad biochemistry. Differences in the fatty acid composition of the gonad reflected the changes in sexual maturation. Mature males and females had significant differences in the fatty acid composition of their gonads, whereas post-spawned individuals showed no gender differences. Male urchins had higher levels of polyunsaturated fatty acids (PUFAs) compared to females, and there was a dramatic reduction in the fatty acids 22:6(n−3) and 20:5(n−3) with increasing maturity stage. Using multivariate statistical techniques, these changes in the fatty acid composition of the sea urchin gonad were linked to habitat related diet differences combined with gender differences. These changes in the fatty acid signatures clearly reflect the dual function of the gonad as both a nutrient store and a reproductive organ.

Embryogenesis of decapod crustaceans with different life history traits, feeding ecologies and habitats: A fatty acid approach

Article

Full-text available

Apr 2007

Variations in embryo size and fatty acid (FA) dynamics during embryogenesis were evaluated in deep-sea pandalids and portunid swimming crabs from the Portuguese continental margin and Madeira Island slope and compared with previous data on neritic and deep-sea lobsters and shrimps (collected between February 2001 and March 2004). Inter-specific variations in embryo size seem to be dictated primarily by phylogeny rather than by differences in reproductive or early life history traits. FA reserves were significantly correlated with embryo size (P<0.001). Principal component analysis revealed differences among three groups (1—neritic caridean shrimps, 2—deep-sea pandalids of the genus Plesionika, and lobsters, 3—portunid crabs and the deep-sea pandalid Chlorotocus crassicornis, Costa 1871). Group 1 was clearly separated by PC1 mainly due to the higher percentage of essential C18 (linoleic and linolenic acids) and C20 (namely eicosapentaenoic) polyunsaturated FA (specific markers of primary producers). PC2 separated Group 2 from Group 3 due to differences in the percentage of several saturated FA (including odd-numbered FA—bacterial markers) and C18 monounsaturated FA (namely 18:1n−9, a general marker of carnivory). Therefore, these differences among groups seem to result from distinctions in diet and ecological niche. Intra-specific differences in FA composition between western and southern Plesionika martia martia (A. Milne-Edwards, 1883) populations may reflect higher water temperatures on the south sub-tropical coast. Lobster embryonic development was more demanding of lipid energy than that of the other decapod species, which may reflect an evolutionary trend in decapod taxa related to an increasing degree of lecithotrophy. However, a lower FA catabolism can be interpreted as an enhanced independence of the newly hatched larvae from external energy sources. Higher FA content at hatching and, as a consequence, a greater independence from the external environment should increase the chances of larval survival.

Codend selection in deep-water crustacean trawl fishery in Portuguese southern waters

Article

Jun 2007
FISH RES

In this paper, the potential improvement of size-selectivity by increasing codend mesh size and changing twine type is addressed for the main commercial species exploited by crustacean trawlers in waters off the Portuguese south coast. Three cruises were conducted between autumn 1998 and summer 1999 onboard the F/V “Porto Bravo”, resulting in a total of 93 valid hauls using 3 different sizes of diamond mesh in the codend (stretched nominal sizes of 55, 70 and 80 mm) and 2 types of twine, polyamide and polyethylene. A non-linear mixed-effects model was employed to include the effect of covariates and between-haul variation in the estimation of codend selectivity parameters for the main target species in this ﬁshery, Norway lobster, Nephrops norvegicus (L.), rose shrimp, Parapenaeus longirostris (Lucas 1846), and ‘blue and red’ shrimp, Aristeus antennatus (Risso, 1816). The chosen selectivity model found a signiﬁcant (p < 0.001) linear effect of mesh size for all three target species, and a signiﬁcant effect of cruise for Norway lobster (p < 0.05) and rose shrimp (p < 0.001). The cruise effect was due to a difference between the autumn 1998 cruise and the two latter cruises. This effect coincides with a change from polyamide twine in the autumn cruise to the use of polyethylene twine in the latter cruises. Other covariates, such as depth, codend-catch weight and species catch weight did not show any systematic effect on selectivity and thus were not included in the ﬁnal models. The retention of a high number of undersized (or immature) individuals, while using the legal minimum mesh sizes, suggests the need for a change in the status quo ﬁshing pattern.

Energy reserves and gonad steroid levels during the reproductive cycle of the Japanese mantis shrimp Oratosquilla oratoria De Haan, 1844 (Stomatopoda: Squillidae) in Pikou Bay, Dalian, China

Article

Mar 2017
J CRUSTACEAN BIOL

This study aimed to characterize the seasonal cycles of energy storage and depletion in different organs of both sexes of the mantis shrimp Oratosquilla oratoria (De Haan, 1844). We sought to relate these findings to the reproductive cycle and environmental factors affecting such cycles and identify the link between steroid concentrations and the reproductive cycle. Individuals were collected monthly (May 2014 to April 2015) in Pikou Bay, Dalian, China, and the biochemical compositions of muscle, hepatopancreas, and gonads analyzed. Two peaks of protein levels were observed in the ovaries in May and November in accordance with the seasonal variations in gonadosomatic index (GSI). An increase in the lipid content of ovaries during gonad maturation was also observed. Protein levels in the hepatopancreas and muscle decreased before May and November in both sexes. Glycogen concentration in the muscle of females peaked in February and September, decreasing during the reproductive months. These subsequently decreased during the peaks in reproduction. In the hepatopancreas of male as well as in the ovaries, the largest reserves of glycogen were observed in the autumn and a subsequent decrease was seen during the transition from autumn to winter. These finding suggest that in O. oratoria both protein and lipids serve as energy reserves for reproduction. Besides, glycogen from either the ovaries or the hepatopancreas of males might be used during periods of intense activity and starvation. Two vertebrate sex steroids, 17β-estradiol and testosterone, were also identified in testes and ovaries, respectively, by means of ELISA. Fluctuating levels of these steroids during the reproductive cycle suggest they might be related to gonadal development in O. oratoria. © The Author 2017. Published by Oxford University Press on behalf of The Crustacean Society. All rights reserved.

Nephrops species

Chapter

Jul 2013

Nephrops norvegicus (L.) is widely distributed in the north-east Atlantic and Mediterranean. The species forms burrows in muddy sediments and is found wherever conditions are suitable. Important fisheries for Nephrops have developed since the 1950s, and it is now one the most valuable demersal species in the north-east Atlantic. Research into the biology of Nephrops dates back over at least a century, and this chapter reviews the current state of knowledge of its biology, ecology and fisheries. The chapter also reviews research into the biology of similar Metanephrops species that are also becoming the focus of important fisheries in New Zealand, Australia and elsewhere.

Fatty Acids of Densely Packed Embryos of Carcinus maenas Reveal Homogeneous Maternal Provisioning and No Within-Brood Variation at Hatching

Article

Apr 2016
BIOL BULL-US

Embryonic development of decapod crustaceans relies on yolk reserves supplied to offspring through maternal provisioning. Unequal partitioning of nutritional reserves during oogenesis, as well as fluctuating environmental conditions during incubation, can be sources of within-brood variability. Ultimately, this potential variability may promote the occurrence of newly hatched larvae with differing yolk reserves and an unequal ability to endure starvation and/or suboptimal feeding during their early pelagic life. The present study evaluated maternal provisioning by analyzing fatty acid (FA) profiles in newly extruded embryos of Carcinus maenas Also assessed were the dynamics of such provisioning during embryogenesis, such as embryo location within the regions of the brooding chamber (left external, left internal, right external, and right internal). The FA profiles surveyed revealed a uniform transfer of maternal reserves from the female to the entire mass of embryos, and homogeneous embryonic development within the brooding chamber. Although C. maenas produces a densely packed mass of embryos that are unevenly distributed within its brooding chamber, this factor is not a source of within-brood variability during incubation. This finding contrasts with data already recorded for larger-sized brachyuran crabs, and suggests that the maternal behavior of C. maenas promotes homogeneous lipid catabolism during embryogenesis.

Biochemical contents of the ovary and hepatopancreas of Uca longisignalis and Uca nr. minax

Article

Sep 2006

The Crustacean Nephrops norvegicus

Chapter

Jan 2008

Immunorecognition and Distribution of Progesterone Receptors in the Chinese Mitten Crab Eriocheir sinensis During Ovarian Development

Article

Apr 2014

Progesterone is an important sex steroid that plays a vital role during ovarian development in crustaceans. In vertebrates, progesterone mediates reproduction via the progesterone receptor (PR). Previous studies have shown that PR is present in the ovary, hepatopancreas, and nerve tissues of some crustacean species. The Chinese mitten crab, Eriocheir sinensis, is an important aquaculture species in China and has become an invasive species in Europe and North America. A better understanding of the relevant reproductive mechanisms could potentially benefit artificial propagation and production of E. sinensis. Our intention was to immunorecognize and immunolocalize PR in the ovary, hepatopancreas, optic ganglion, brain ganglion, and thoracic ganglion of female E. sinensis using Western blot and immunohistochemistry. Changes in the distribution of PR were also investigated in these tissues during ovarian development. With an apparent molecular weight of 70 kDa, PR was identified in the optic, brain, and thoracic ganglion of female E. sinensis. During ovarian development, follicle cells were stained with positive PR at each ovarian stage. In germinal cells, positive PR was found in the cytoplasm only during the early ovarian development stages (I-III), whereas positive PR stained in the nucleus of germinal cells from stage III-stage V. In the hepatopancreas, PR was localized in the nucleus of resorptive cells as well as in the cytoplasm and nucleus of fibrillar cells for all stages of ovarian development. On the contrary, no PR-like substance was found in the other types of hepatopancreatic cells, such as blisterlike cells and embryonic cells, during ovarian development. However, a PR-like substance was detected in the nerve tissues of female E. sinensis. In the optic ganglion, PR was localized in the nucleus only of nerve cells. In the thoracic ganglion, PR was detected in the cytoplasm and nuclei of nerve cells during all ovarian development stages, with stronger detection during late ovarian development (stages III-V) rather than early (stages I and II). In addition, PR was localized in the brain ganglion, which is supported by evidence that the nuclei of nerve cells stained positively for PR antibody during all ovarian development stages. We suggest that progesterone not only regulates vitellogenesis and ovarian development directly by binding PR in the ovary and hepatopancreas, but also modulates indirectly ovarian development through nerve tissue.

Quantitative Protein Profile of Three Macrobrachium Species during Reproductive Cycle

Article

Jul 2011
Asian J Anim Vet Adv

The total protein content of Hepatopancreas, hemolymph and ovary of adult freshwater prawns Macrobrachium malcomsonii (H. Milne Edwards) Macrobrachium rosenbergii, (H. Milne Edwards) Macrobrachium lammarei (H. Milne Edwards) was studied in relationship with gonadosomatic index during different stages (early-mature, mature and spent) of reproductive cycle. The gonadosomatic index increased drastically during maturation in all three species, when compared to the respective early-mature ovaries. The protein content in different organs was estimated by Bradford method. The protein content in hepatopancreas and hemolymph recorded a gradual decline during maturation stages while a marked increase was noted in ovary during maturation and at the spent stage, protein content was highest in hepatopancreas, whereas very lowest in hemolymph and ovary during the reproductive cycle in all three freshwater prawn species.

INFLUENCE OF ENVIRONMENTAL CONDITIONS ON BIOGEOCHEMICAL PROCESSES IN THE ARABIAN SEA: OXYGEN AND BENTHOS

Article

Rachel Jeffreys

Reproduction disorders in the benthic amphipod Monoporeia affinis: An effect of low food resources

Article

Full-text available

May 2008
AQUAT BIOL

The aim of the present study was to investigate the influence of food availability on reproduction by comparing the response of reproductive biomarkers of a deposit-feeding amphipod Monoporeia affinis in 2 Swedish lentic environments (Lake Vanern and Lake Vattern) differing in eutrophication level, during the period between 1995 and 2002. In ultraoligotrophic Lake Vattern, a very low fecundity (living eggs female(-1)) was found and severe embryo aberrations in terms of undifferentiated eggs (% female(-1)), dead eggs (% female(-1)) and the percent of females with dead broods were recorded. A significant negative correlation between fecundity and (1) undifferentiated eggs and (2) dead eggs and broods were obtained in both lakes. Amphipods collected in Lake Vattern in 2001 showed significantly lower concentrations of lipids-mainly triacylglycerols (TAG)-and of fatty acids (FAs) than amphipods collected in the more eutrophic Lake Vanern. Dramatically increased spring bloom diatom abundance in Lake Vattern resulted in increased fecundity and lipid and fatty acid concentrations (namely monounsaturated fatty acids, MUFA) and decreased embryo aberrations. A significant relationship between fecundity and diatom biovolume in Lake Vanern and total algal biovolume in Lake Vattern was found. No other alga taxa influenced the fecundity. In Lake Vattern total algal biovolume was negatively related to undifferentiated eggs. MUFA and saturated fatty acids (SFAs) seem to be important for vitellogenesis and oogenesis and also constitute fuel during embryogenesis. Other environmental variables in bottom waters (i.e. oxygen, pH and temperature) and sediment organic content did not influence the reproduction variables. Our findings strongly suggest a relationship between embryo aberrations (e.g. undifferentiated eggs and dead broods) and low food resources.

Biochemical composition and digestive enzyme activities during the embryonic development of the redclaw crayfish, Cherax quadricarinatus

Article

Sep 2008

The biochemical composition and the activity of five digestive enzymes of embryos were studied during embryonic development in the redclaw crayfish, Cherax quadricarinatus (Von Martens, 1868), in order to investigate the relationship between embryonic development and the utilization of yolk. Carbohydrates remained a minor constituent of the yolk as a whole. The contents of total proteins and total amino acids (TAA) were all observed to decrease. Among the essential amino acids (EAA), the contents of leucine and arginine were relatively high, while of the non-essential amino acids (NEAA), the most important components were glutamine and aspartic acid. The contents of total lipids (TL) decreased during embryonic development, and the predominant fatty acids of both neutral lipids (NL) and polar lipids (PL) were C16:0, C18:0, C18:1ω9, and C18:3ω3. The five digestive enzymes tested all showed changes in their activities. The specific activities of pepsin and trypsin gradually increased in the earlier stages of embryonic development, pepsin decreased rapidly in later stages, while trypsin still kept a high level of activity. The specific activity of amylase changed in a "V" shape and reached high values again in later stages. The specific activities of cellulase and lipase showed relatively low values. It is shown that carbohydrates may play an important role in synthesizing many specific compounds to participate in signal transmission and in forming the carapace. Proteins and lipids were the dominating construction and energy substances; proteins were primarily consumed in the early stages, as against lipids in later stages. Saturated fatty acids (SFA) (16:0 and 18:0) and monounsaturated fatty acids (MUFA) (16:1ω7 and 18:1ω9) were always used for energetic purposes and polyunsaturated fatty acids (PUFA) (20:5ω3 and 22:6ω3) were important as structural components of cell membranes and in the development of the central nervous system. The activities of the digestive enzymes were controlled by their genes and expressed sequentially during embryonic development. They hydrolyse the yolk and provide construction substances and energy sources for the formation of tissues, organs, and various systems in general. French La composition biochimique et l'activité de cinq enzymes digestives d'embryons ont été étudiées au cours du développement embryonnaire de l'écrevisse à patte rouge, Cherax quadricarinatus (Von Martens, 1868), dans le but d'investiguer les inter-relations entre le développement embryonnaire et l'utilisation du vitellus. Les glucides représentent un constituant mineur du vitellus. Les contenus en protéines totales et en acides aminés totaux (TAA) diminuent. Parmi les AA essentiels (EAA), les contenus en leucine et arginine ont été relativement élevés, tandis que parmi les acides aminés non-essentiels (NEAA), les composés les plus importants ont été la glutamine et l'acide aspartique. Les contenus en lipides totaux (TL) diminuent au cours du développement embryonnaire, et les acides gras prédominants parmi, à la fois les lipides neutres (NL) et les lipides polaires (PL), étaient C16:0, C18:0, C18:1ω9, et C18:3ω3. Les cinq enzymes digestives testées montrent toutes un changement dans leur activité. Les activités spécifiques de la pepsine et de la trypsine augmentent progressivement au cours des premiers stades du développement embryonnaire, la pepsine décroît rapidement dans les derniers stades, tandis que la trypsine conserve un degré d'activité élevé. L'activité spécifique de l'amylase change selon une forme en V et atteint à nouveau un niveau élevé dans les derniers stades. Les activités spécifiques de la cellulase et de la lipase montrent des valeurs relativement basses. Il est montré que les glucides pourraient jouer un rôle important en synthétisant de nombreux composés spécifiques pour participer au signal de transmission et à la formation de la carapace. Les protéines et les lipides ont été les substances dominantes pour la construction et l'énergie; les protéines ont été prioritairement utilisées dans les jeunes stades et les lipides dans les derniers stades. Les acides gras saturés (SFA) (16:0 et 18:0) et les acides gras mono-unsaturés (MUFA) (16:1ω7 et 18:1ω9) ont toujours été utilisés pour les besoins énergétiques, et les acides gras poly-unsaturés (PUFA) (20:5ω3 et 22:6ω3) ont été important comme composés structurels des membranes cellulaires et dans le développement du système nerveux. Les activités des enzymes digestives ont été contrôlées par leur gênes et exprimés séquentiellement au cours du développement. Elles hydrolysent le vitellus et fournissent les substances de construction et la source d'énergie pour la formation des tissus, des organes et des différents systèmes.

Eyestalk hormones on molting and reproductionconcepts of Neuropeptide hormones in crab

Book

Full-text available

Jan 2012

The reproductive cycle of Norway lobster

Article

Full-text available

May 2009
J ZOOL

The reproductive biology of female Norway lobster Nephrops norvegicus was studied throughout an annual cycle from January to December 2007 in Pagasitikos Gulf, a large semi-enclosed Gulf in the central west Aegean Sea, in Greece. Six ovarian maturation stages were described to follow gonadal development, based on the combined external observation and histological examination of the ovary. Reproduction showed clear seasonality both in terms of ovarian maturation and brooding period. The proportion of fully mature females in the catch increased from January to the summer months with a peak in June. The species has a protracted brooding period that peaks in November and December, while the release of eggs from females' pleopods occurs from January to March. The size at which 50% of females reached sexual maturity was estimated, using a logistic model, to be 28.1 mm of carapace length. The undiscovered reproductive dynamics will be valuable for optimizing population models and management strategies for this important fishery resource.

Nephrops Species

Chapter

Nov 2007

Population decline of amphipod Monoporeia affinis in Northern Europe: Consequence of food shortage and competition?

Article

Full-text available

Dec 2008
J EXP MAR BIOL ECOL

In the present study, we investigate the effects of food quality (with three distinct algal diets) and quantity (high vs. low carbon and nitrogen contents) and competition (with natural polychaete competitor, Marenzelleria spp) on the semelparous amphipod Monoporeia affinis fitness and reproduction. Contrary to other studies on this species, our results showed that amphipod females have the ability to adjust their offspring investment when conditions were significantly altered before mating in terms of food quantity, while food quality was of less importance. In fact, there was only a low beneficial effect on amphipod reproduction and embryonic development of a presumed high quality diatom diet. Also, the presence of a natural competitor did not affect amphipod reproductive outcome. The results are viewed in the context of a dramatic decline observed on the amphipod populations in the Gulf of Bothnia. Though, several plausible hypotheses have been suggested for the decline, including competition, new anthropogenic substances, hypoxia and predation, we hypothesize that the population decline is related to food shortage and malnutrition due to an increased percentage low quality terrestrial carbon (rich in humus) from river outflow into the Gulf of Bothnia. Concomitantly, the bacterial food web was enhanced, which has a lower trophic efficiency. We also suggest that a secondary effect of malnutrition is an increased susceptibility to other types of stressors such as contaminants and parasites.

Influence of eyestalk hormones on the Metabolism and Ionic Regulation of the Crab Poryunus pelagicus (Lineaus, 1857)

Article

Feb 2011

Biochemical studies are very important from the nutritional point of view. The biochemical constituents in animals are known to vary with season, size of the animal, stage of maturity, temperature and availability of food also to elucidate the osmoregulatory ion concentration. The present study quantified the nutritive value of sea food and the ionic regulation which is good measure for leading a fruitful aquaculture. So for methods used for the detection of sodium and chlorideion concentrations are Elico digital flame photometer. Biochemical composition of hemolymph and different tissues was carried out and it has been observed that more protein content were found in eyestalk extract injected female crabs (64.0%) while as less percentage was found in normal female crab (10.66%) and lipids were found more in injected female and ablated male (16.8 mg mL-1) while it is very low in normal male crab (12.6 mg mL-1). Carbohydrate percentage was found more in ablated male (7.6%) and less in eyestalk extract injected male (3.3%). The variations of the sodium and chloride ionic level in the hemolymph were studied by comparing the levels in the experimental animals with that of control animals. In the ablated animals of male crabs, the hemolymph showed decreased sodiumionic level (428 milliequivalent L-1) when compared to control animals while as in female it showed increase in the Na+ ion concentration (454 milliequivalent L-1). However, eyestalk extract injected animals of both sexes at the final stage showed a much increase in the sodium ionic level when compared to control and ablated animals.

Survival, food consumption and growth of Norway lobster (Nephrops norvegicus) kept in laboratory conditions

Article

Full-text available

Sep 2010
Integr Zool

Eleni Mente

Successful commercial aquaculture of crustacean species is dependent on satisfying their nutritional requirements and on producing rapidly growing and healthy animals. The results of the present study provide valuable information for feeding habits and growth of Nephrops norvegicus L., 1758) under laboratory conditions. The aim of the present study was to examine food consumption, growth and physiology of the Norway lobster N. norvegicus under laboratory conditions. N. norvegicus (15 g wet weight) were distributed into 1001 tanks consisting of five numbered compartments each. They were fed the experimental diets (frozen mussels and pellets) for a period of 6 months. A group of starved Nephrops was stocked and fasted for 8 months. Although Nephrops grew well when fed the frozen mussels diet, feeding on a dry pellet feed was unsatisfactory. The starvation group, despite the fact that showed the highest mortality (50%), exhibited a remarkable tolerance to the lack of food supply. The study offers further insight by correlating the amino acid profiles of Nephrops tail muscle with the two diets. The deviations from the mussel's diet for asparagine, alanine and glutamic acid suggest a deficiency of these amino acids in this diet. The results of the present study showed that the concentrations of free amino acids are lower in relative amount than those of protein-bound amino acids, except for arginine, proline and glycine. The present study contributes to the improvement of our knowledge on nutritional requirements of the above species.

A comparative study of the feeding ecology of Nephrops norvegicus (L.), (Decapoda: Nephropidae) in the bathyal Mediterranean and the adjacent Atlantic

Article

Full-text available

Dec 1998

A comparative study of the feeding ecology of Nephrops norvegicus was carried out on a seasonal basis simultaneously in seven locations in the Eastern and Western Mediterranean and the adjacent Atlantic: the south coast of Portugal, Faro; the Alboran Sea, Malaga; the Catalan Sea, Barcelona; the Ligurian Sea, Genoa; theTyrrhenian Sea, Pisa; the Adriatic Sea, Ancona and the Aegean Sea, Gulf of Euboikos, The major groups observed (frequency of occurrence method) in the stomachs of Nephrops norvegicus were decapod crustaceans, other crustaceans (euphausids and peracarids) and fish. The results obtained showed no significant differences between sites or seasons, and can be considered very consistent. All major taxa were present in the diet at all sites and for all seasons, a fact that can be explained by the great similarity of the bathyal fauna in all sites, which provide a major trophic resource for N. norvegicus. The percentage of fullness was also estimated per site and season, and we registered a clear decrease of this value during the summer period for all sites, except the Tyrrheanian Sea, where the lowest value was found in autumn. PCA - analysis did not clearly separate the regions (sites). The Shannon-Weaver (H'), index of diversity, was also determined per site and season, and we found a significant difference between the values of the Atlantic coast and the Western Mediterranean when compared with those of the Eastern Mediterranean.

The decapod hepatopancreas

Article

Full-text available

Jan 1979
OCEANOGR MAR BIOL

Glycogen depletion and altered copper and manganese handling in Nephrops norvegicus (L.) following starvation and exposure to hypoxia.

Article

Full-text available

Jan 1994

Nephrops norvegicus exposed to starvation and hypoxia in the field as well as in the laboratory exhibited marked differences in glycogen reserves, haemolymph haemocyanin concentrations, and tissue copper and manganese contents. Muscle glycogen concentration was reduced by ca 50 % in lobsters collected from hypoxic field conditions. Glycogen concentrations were reduced to ca 3 % of initial values in muscle and 10 % in midgut gland following 7 mo starvation in the laboratory. Haemolymph haemocyanin concentration was markedly reduced in N. norvegicus exposed to severely hypoxic conditions although haemolymph copper concentration remained virtually unchanged. Starvation resulted in a slower reduction of haemocyanin concentration than was associated with hypoxia. Starvation resulted in a net loss of copper after 7 mo. Experimental exposures to moderate or severe hypoxia were not associated with net losses of copper, although in long-term moderate hypoxia the whole body copper load was redistributed, especially to the midgut gland increasing the concentration there 4 times. Redistribution of copper to the midgut gland did not occur in N. norvegicus exposed to severe hypoxia in the field. Three- to four-fold lower copper concentrations were found in the midgut glands of hypoxic lobsters (compared to controls from normoxic areas). As well as low copper concentrations, these lobsters had 2 to 4 times higher manganese concentrations in internal tissues. In the absence of sediment, manganese concentrations and contents were not influenced by laboratory exposure to hypoxia.

Diets of deep-water pandalid shrimps on the Western Mediterranean slope

Article

Full-text available

Jun 1993

Joan Cartes

The feeding habits of 3 deep-water species of pandalid shrimps occurring in the Catalan Sea (Western Mediterranean) were studied. All specimens were collected from 1988 to 1990 using bottom trawls at depths ranging between 380 and 1249 m. A total of 71 specimens of Plesionika edwardsi, 176 of P. martia, and 213 of P. acanthonotus were analyzed. Pandalid shrimps were active predators of macroplankton species. The diets of P. edwardsi and P. martia were quite similar and consisted primarily of benthopelagic eucarid crustaceans (Pasiphaea sp., euphausiids). P. acanthonotus is smaller, and its diet was based on smaller prey (siphonophores, hyperiids, euphausiids). Seasonal changes in the diets of bathyal pandalids were important. Planktonic organisms were their main food resource, and pandalid diets corresponded with changes in the abundance of available planktonic resources in the Western Mediterranean. Thus, bathymetric distribution and abundance of pandalid shrimps along the slope were related to the influence of the mesopelagic fauna on bathyal communities, which is commonly accepted to decrease with depth, The bathymetric distribution of pandalids is also discussed in relation to a possible competitive interaction for similar resources among certain pandalid species.

Biochemical composition of Nephrops norvegicus - Changes associated with ovary maturation

Article

Full-text available

Sep 1997

Changes in the biochemical composition of the ovary of Nephrops norvegicus (L.) were examined throughout maturation at stations with fast and slow growing individuals in Scottish waters and in the Mediterranean. Ovary index (ovary wt:total body wt) increased significantly with maturation. Lipid, protein and water content of the ovary increased with maturation, while carbohydrate content decreased. Similar changes were also identified in the hepatopancreas. Significant spatial differences in ovary and hepatopancreas composition were identified, which may be related to whole-body growth rate. The ovary maturation scale commonly used for N. norvegicus was shown to reflect biochemically distinct stages in ovary development.

Direct Transesterification of All Classes of Lipids in a One-Step Reaction

Article

Full-text available

Feb 1986

Conventional techniques for the determination of fatty acid composition of lipids require solvent extraction, purification, hydrolysis, and derivatization procedures that are both lengthy and cumbersome. A 1-hr direct transesterification procedure carried out in methanol-benzene 4:1 with acetyl chloride circumvented all these steps and was applicable for analysis of both simple (triglycerides) and complex lipids (cholesteryl esters, phospholipids, and sphingomyelin). Recoveries (greater than 95%) of standards unaffected by the presence of 5% water and 200 mg of silica suggested that the technique could be used for the quantitative analysis of total fatty acids as well as of fatty acids in classes of lipids separated on silica from biological samples. When compared to the Folch procedure, the technique led to a 20.1% increase in total fatty acids for plasma, 3.9% for feces, 7.4% for bile, and 9.7% for rat liver. We therefore conclude that this one-step direct transesterification procedure is superior to currently used methods, not only because of its simplicity and speed, but also because of its added precision.

Accumulation of ovarian ecdysteroids in synchronization with gonadal development in the giant freshwater prawn, Macrobrachium rosenbergii

Article

Jan 1991

Interrelationship between ascorbic acid and trace elements in ovarian development in fish

Article

Jan 1984

Lipid Metabolism in Destalked Prawn Penaeus Japonicus: Induced Maturation and Transfer of Lipid Reserves to the Ovaries

Article

Jan 1988

Double tracer experiment using radioactive fatty acids was conducted in order to verify the transfer of lipid reserves to the ovaries during the ovarian maturation of the prawn Penaeus japonicus. The prawns were fed with a diet containing both palmitic acid (16:0)-3H and linolenic acid (18:3ω3)-14C, held for 1 day, and then maintained for 5 days with and without destalking. One day after feeding of the diet, both lipids-3H and lipids-14C were mainly distributed in the hepatopancreas as phosphatidylcholines (PC) and free fatty acids (FA) and in the muscle as PC. Bilateral destalk-ing resulted in the induction of ovarian maturation and also the increase in ovarian radioactive triglycerides (TG) and PC with a concomitant decrease in hepatopancreatic radioactive TG and PC. Thus, the destalking enhanced a transfer of body lipid reserves, particularly hepatopancreatic lipids, to the ovaries which accumulated TG and PC as the major lipid classes. From the 3H/14C ratios of ovarian PC and TG, it is likely that the major ovarian PC accumulated during the induced ovarian maturation are rich in ω3-fatty acids, possibly 18:30, 20:5ω3, 22:6ω3, etc., rather than 16:0 and its metabolites, whereas the major ovarian TG consist of 16:0 and its metabolites rather than ω3-fatty acids as acyl groups.

Effect of Dietary Phospholipids and n-3 Highly Unsaturated Fatty Acids on Ovarian Development of Kuruma Prawn

Article

Jan 1993

The influence of diets complete in or free from either phospholipid (soybean lecithin) or n-3 highly unsaturated fatty acids (n-3 HUFA. squid liver oil) on the gonadosomatic index (GSI) and tissue lipid composition of ablated female Penaeus japonicus (mean weight=20,2±0.9 g) were determined. Bilateral eyestalk ablation was performed 31–37 days after feeding on experimental diets and GSI was examined after 20 days of each prawn’s ablation. Supplementation of both phospholipid and n-3 HUFA resulted in the highest GSI (3.0±0.8, P<0.05). The absence of either phospholipid or n-3 HUFA significantly retarded GSI develop-ment (1.3±0.6 and 1.4±0.5, respectively). The complete diet produced higher total lipid in ovaries, hepatopancreas, and muscle than the incomplete diets. Regardless of diets, ovaries and muscle had greater polar lipid deposits, in contrast to the hepatopancreas wherein neutral lipid was dominant. Triglycerides and phosphatidylcholine were the dominant lipids in the ovaries. © 1993, The Japanese Society of Fisheries Science. All rights reserved.

The role of nutrition in maturation, reproduction and embryonic development of Decapod crustacean: A review

Article

Jan 1990

K.E. Harrison

Relationship between Maturation and Biochemical Composition of the Gonads and Digestive Glands of the Shrimps Penaeus aztecus Ives and Penaeus setiferus (L.)

Article

May 1989

Maturation in Penaeus aztecus and P. setiferus was evaluated by visual, histological, and biochemical observations. Changes in carbohydrate, lipid, and protein contents were described in gonads and digestive glands of both males and females, and in the terminal portion of the male reproductive tract (terminal ampullae and vasa deferentia combined). During gonadal maturation of both species, carbohydrate, protein, and lipid contents of the ovaries increased. The largest absolute changes were in the amount of protein and the greatest relative increases occurred in the amount of lipid. In digestive glands of females, changes in biochemical composition differed between the species: in P. aztecus carbohydrate and protein contents of the digestive glands increased during maturation, but in P. setiferus the lipid content of the digestive glands decreased during maturation. Results suggest that mobilization of stored lipid from the digestive gland to ovaries may be more important in P. setiferus than in P. aztecus. The testes were relatively small and the terminal ampullae and vasa deferentia made up a larger portion of the male reproductive system than did the testes. In mature males, the protein, lipid, and carbohydrate contents of testes were larger in P. setiferus than in P. aztecus, but protein, lipid, and carbohydrate contents of combined terminal ampullae and vasa deferentia were larger in P. aztecus than in P. setiferus. In P. setiferus, protein contents of both testes and combined terminal ampullae and vasa deferentia were larger in mature males than in developing males. Protein and lipid contents of digestive glands of males did not differ between the species or among the maturation stages.

In Vivo Conversion of Cholesterol to Steroid Hormones in the Spiny Lobster, Panulirus japonica

Article

Jan 1971
NIPPON SUISAN GAKK

The present study deals with the in vivo conversion of cholesterol-14C to steroid hormones in the spiny lobster, Panulirus japonica. Two days after injection of cholesterol-14C to the spiny lobster, the separation of bioconversion products was carried out about the hepatopancreas, ovaries, and blood. As the bioconversion products, the radioactive progesterone, 17α-hydroxyprogesterone, and-rostenedione, and testosterone were identified from the hepatopancreas, ovaries, and blood. Moreover, from the hepatopancreas, deoxycorticosterone and corticosterone were detected. From these results, it is suggested that the spiny lobster, Panulirus japonica, may possess the enzyme systems catalyzing the conversion of cholesterol to steroid hormones.

Biostatistical Analysis. 3rd Ed

Book

Jan 1999

Jerrold H. Zar

Variation in Lipid Compositions during the Ovarian Maturation of the Prawn

Article

Jan 1983
NIPPON SUISAN GAKK

This paper presents the variation in lipid compositions during the ovarian maturation of the prawn Penaeus japonicus. The ovarian lipid concentrations increased during the slight mature and yellow ovarian periods, remained at roughly constant levels during the subsequent ovarian period to spawning, and then decreased to low levels at the spent ovaries. The hepatopancreatic lipid concentrations increased with increasing maturity of the ovaries, reached a maximum level at the yellow period of ovaries, and then decreased during the subsequent period to spawning. These results suggest the possible movement of hepatopancreatic lipids to the ovaries during the ovarian maturation. Both triglycerides and phospholipids were responsible for the increase in ovarian lipid concentrations during the sexual maturation. The fatty acid composition of lipids, trigly-cerides, and phospholipids of the ovaries did not vary markedly during the ovarian maturation.

Changes in lipid and protein during starvation and the moulting cycle in the Tiger Prawn, Penaeus esculentus Haswell

Article

Apr 1983
J EXP MAR BIOL ECOL

Tiger prawns, Penaeus esculentus Haswell (mean wt 20.8 ± 0.3 g, range 13.9–27.7 g) contained 1–2% extractable lipid, 13% protein (biuret method) and 71–74% water (wet wt). In 21 days, the weight of fed prawns increased by 3% and that of starved prawns decreased by 4.4%. Protein was the major energy source during 14 days of starvation, with a loss of 550 mg of total protein compared with a loss of 84 mg of total lipid. The absolute amount of water present remained constant. Of three different tissue compartments, abdomen, cephalothorax, and digestive gland, the abdomen contributed the most protein (330 mg) and lipid (35 mg) during 14 days of starvation. Digestive gland, although containing the largest percentage wet wt of lipid, accounted for only 8.3% of the total lipid in the prawn, and contributed only 18 mg of lipid in 14 days of starvation. Lipid concentration in the digestive gland increased during early premoult (stage D4) and dropped in late premoult (stage D4). Resting oxygen consumption rate remained constant at ≈0.1 ml · g−1 · h−1 at 25°C during 21 days of starvation.

Patterns of resource use in deep-water decapods

Article

Jul 1999

The distribution patterns and feeding habits of 4 deep-water decapod species were investigated from samples collected in experimental trawl surveys carried out along the continental slope of Crete (Eastern Mediterranean) in 1994 to 1995, at depths between 100 and 1000 m. Despite their distribution overlap, the differences in the distribution patterns of the species along the depth gradient were clear, with Plesionika ensis and Polycheles typhlops occurring at greater depths than Parapenaeus longirostris and Plesionika heterocarpus. Stomach content analysis revealed that all species were active predators of benthic invertebrates, while scavenging activity became more important at depths below 500 m. The species exhibited highly diverse diets, but dietary diversity was higher for those inhabiting shallower depths. Ontogenetic dietary shifts were pronounced, although dietary patterns were also significantly affected by season and depth. Interspecific dietary overlap was less than intraspecific overlap between size classes and between months. Feeding intensity was associated with the distribution patterns of the species and decreased with depth, thus it was significantly lower for the species at the deepest depths, P. typhlops and P. ensis. Dietary patterns of the species examined were quite similar and differences noted were more consistent with depth-related changes in available food resources than with changes in the position of the species in the food web. Since dietary overlap among the species when they co-occur was high, it is possible that competitive trophic interactions accounted for the low overlap in the bathymetrical distribution of the species examined. Such interactions may be of fundamental importance on the deep-sea bottoms in the Eastern Mediterranean since environmental parameters such as temperature and salinity are rather constant.

Effect of environmental conditions on fatty acid composition of the red alga Porphyridium cruentum: Correlation to growth rate

Article

Sep 1988

The lipid and fatty acid composition of Porphyridium cruentum was determined as a function of light intensity, temperature, pH, and salinity. In cultures cultivated at the optimal temperature under non-limiting light conditions, eicosapentaenoic acid was the main polyunsaturated fatty acid. When growth rate was reduced by decreased light intensity, increased cell concentration, suboptimal temperature, suboptimal PH, or increased salinity, the content of eicosapentaenoic acid decreased and that of arachidonic acid increased, the latter becoming the major polyunsaturated fatty acid. Key index words: arachidonic acid; eicosapentaenoic acid; environment effects, microalgal mass cultivation; Porphyridium

Glycogen depletion and altered copper and manganese handling in Nephrops norvegicns (L.) following starvation and exposure to hypoxia

Article

Dec 1995

A review of dietary study with shrimp and prawn

Article

Oct 1976
AQUACULTURE

Michael B. New

The results of dietary trials with shirmp and prawns published in the decade ending in early 1976 are reviewed. Current knowledge and priorities for future work are assessed under the headings: palatability and physical dietary structure, lipids and sterols, protein, carbohydrate, minerals, vitamins and larval feeding. The problems of drawing quantitative comparisons between the work of different authors are discussed and suggestions for standardizing techniques for dietary trials are made.

Changes in mass and chemical composition during the molt cycle and ovarian development in immature and mature Penaeus indicus Milne Edwards

Article

Dec 1980
Comp Biochem Physiol Physiol

1.1. Absolute changes in body composition (mass, water, protein, lipid, ash, energy) during the moult cycle and ovarian development were expressed in terms of a standard prawn of given length.2.2. During postmoult (A-B) the water content remains approximately constant but increases significantly to reach a maximum at stage D2. Water is lost with increasing ovary maturation.3.3. Changes in fresh mass, protein and lipid follow a similar pattern during the moult cycle but during ovary development, due to water loss, the fresh mass declines while the mass of the organic body constituents increase.4.4. The inorganic body constituents rise sharply from stage A to B of the moult cycle and then remain constant but do not change during ovary development.

Lipid metabolism of the prawn Penaeus japonicus during maturation: Variation in lipid profiles of the ovary and hepatopancreas

Article

Dec 1989
Comp Biochem Physiol B Biochem Mol Biol

1.1. Lipids (TL) were extracted from the ovary and hepatopancreas of prawns, Penaeus japonicus, with varying degrees of ovarian maturation and were analysed for lipid class composition, fatty acid composition of triglycerides (TG) and phosphatidylcholine (PC), and possible fatty acid combination of PC and phosphatidylethanolamine (PE).2.2. The concentrations (% of fresh wt) and quantities (mg/prawn) of ovarian TL increased slightly and drastically, respectively, with increasing maturity in terms of gonadosomatic index (GSI). TG, PC and PE were the major lipid classes responsible for increases in the quantity of ovarian TL during maturation.3.3. In the ovary and hepatopancreas, as ovarian maturation proceeded, TG showed increases in the proportion of monoene fatty acids such as 16:1 and 18:1, whereas PC exhibited increases in the proportion of highly unsaturated fatty acids such as 20:5ω3 and 22:6ω3 with a concomitant decrease in 16:0 and 16:1.4.4. No marked variation was found in the proportion of the possible fatty acid combinations, in terms of carbon numbers, of both ovarian PC and PE during maturation.

Lipid metabolism of the crab Pachyrapsus marmoratus during vitellogenesis

Article

Jan 1988
BIOCHEM SYST ECOL

Vitellogenesis in the female crab Pachygrapsus marmoratus induces important variations in all lipid classes of the whole animal, the hepatopancreas, hemolymph and ovary. Exuviation (moulting), which happens during the reproductive cycle of Pachygrapsus marmoratus, reduces the mobilization of the lipids in the hepatopancreas and their transfer via the hemolymph to the ovary. All lipid fractions decrease after egg laying. Eggs are rich in phospholipids which are essential constituents of embryonic membranes and in triglycerides which serve as nutrients. The polyunsaturated fatty acids increase during the ovocyte maturation and are transported to the eggs.

Lipid metabolism of the male crab Pachygrapsus marmoratus during the molting cycle

Article

Nov 1986
BIOCHEM SYST ECOL

The moult induces important variations in the concentrations and fatty acid composition of lipid classes during the moulting cycle of the male crab Pachygrapsus marmoratus. Phospholipids are the predominant lipid class. The high levels in total saturated fatty acids but also in oleic and palmitic acids result of the semi-terrestrial ethology of this grapsidae. The hepatopancreas presents the most notable variations in the lipid concentration during the moulting cycle. Transport of hepatopancreatic lipids through the hemolymph to the periphery occurs during the end of premolt, just before the new tissues constitution.

In Biostatistical Analysis

Article

Jan 1999

J. H. G. Zar

Nephrops norvegicus population and morphometrical characteristics in relation to substrate heterogeneity

Article

May 1997
FISH RES

Norway lobster (Nephrops norvegicus) populations were sampled by trawling over the Catalan Sea (NW Mediterranean) continental shelf and slope, covering the whole depth range for the species in the area studied (about 100–700 m). Sediment samples were collected and analysed to characterise the substrate of this burrowing decapod crustacean. Univariate and multivariate statistical methods were employed to study some biological parameters of the Nephrops populations and their relationship to environmental parameters. Cluster analysis of sediments indicated two main substrate environments in the study area: shelf and slope. Statistical analysis of Nephrops morphometrical and population data showed that Norway lobsters dwelling on the shelf differed significantly from slope-dwelling individuals in morphometrical measurements, relative growth and female sexual maturity. Canonical correlation analysis allowed us to establish a correspondence between these biological differences and some variables of the sediment, grain size and redox potential. It is argued that grain size and, to a lesser extent, redox potential determine relative growth and morphometrical differences in NW Mediterranean Nephrops populations. Temperature differences play a minor role, explaining only the advancement of sexual maturation in female individuals of the slope.

Determination of Starch and Cellulose with Anthrone

Article

Jan 1949

Change in fatty acid profile during larval development of freshwater prawn Macrobrachium rosenbergii (de Man)

Article

Dec 2001
AQUAC RES

The fatty acid profile of Macrobrachium rosenbergii (de Man) larvae grown under hatchery conditions was studied during development from larval stage I to IX. The larvae were reared under a ‘modified static green water’ system with a modification in which the tanks were not seeded by green water at the beginning of culture period. Feeding with newly hatched Artemia nauplii started at stage II with five or six Artemia per larva, which was then gradually increased to 60 organisms per larva at stage IX when the study was terminated. In general, fatty acid composition changed during larval development, with the greatest variations observed from stage I to stage III. Monounsaturated fatty acids constituted the major moiety of fatty acids of stage I whereas polyunsaturated fatty acids were the dominant fatty acid class in later developmental stages. Moreover, polyunsaturated fatty acids were dominated by n-6 series in stage I and by n-3 series for the rest of the larval stages. The major fatty acids of the stage I larvae were palmitic (16:0), oleic/vaccenic (18:1) and linoleic (18:2n-6) acids, whereas for the rest of the larval stages, palmitic (16:0), stearic (18:0), oleic/vaccenic (18:1), linolenic (18:3n-3) and eicosapentaenoic (20:5n-3) acids were the prominent fatty acids. Although decreases in total saturated fatty acids and monounsaturated fatty acids were observed, polyunsaturated fatty acids tended to increase during larval development. Unlike penaeid larvae, M. rosenbergii larvae appeared to have sufficient capability to convert palmitic (16:0) acid to stearic (18:0) acid. Moreover, dietary linoleic (18:2n-6) and linolenic (18:3n-3) acids appeared to be converted to arachidonic (20:4n-6) and eicosapentaenoic (20:5n-3) acids to meet larval demand for such highly unsaturated fatty acids respectively.

Effect of environmental conditions on fatty acid composition of the red algaPorphyridium crientum: correlation to growth rate. J. Phycol. 24: 328-332

Article

Mar 2008
J PHYCOL

The lipid and fatty acid composition of Porphyridium cruentum was determined as a function of light intensity, temperature, pH, and salinity. In cultures cultivated at the optimal temperature under non-limiting light conditions, eicosapentaenoic acid was the main polyunsaturated fatty acid. When growth rate was reduced by decreased light intensity, increased cell concentration, suboptimal temperature, suboptimal pH, or increased salinity, the content of eicosapentaenoic acid decreased and that of arachidonic acid increased, the latter becoming the major polyunsaturated fatty acid.

Biosynthesis of sterols in the lobster, Panulirus japonica, the prawn, Penaeus japonicus, and the crab, Portunus trituberculatus

Article

Mar 1971
Comp Biochem Physiol B Biochem Mol Biol

1.1. In the present study, the sterol-synthesizing abilities of the lobster, Panulirus japonica, the prawn, Penaeus japonicus, and the crab, Portunus trituberculatus, were investigated by using acetate-1-14C.2.2. It was found that the three species of marine crustaceans are capable of synthesizing fatty acids and some non-saponifiable materials. However, under the present experimental conditions, these animals did not incorporate acetate-1-14C into sterols.

Lipid absorption and utilization in the Norwegian lobster, Nephrops norvegicus (L.)

Article

Feb 1981
J EXP MAR BIOL ECOL

W. Dall

The role of the digestive (mid-gut) gland in absorption, distribution, and utilization of lipids was investigated in Norwegian lobsters, Nephrops norvegicus (L.) during summer. Glycerol tri[1-14C]palmitate was incorporated into food pellets and the subsequent distribution of label followed throughout the body. Digestion and absorption from the foregut was completed 8–12 h after ingestion, but label began leaving the digestive gland after only 4 h and became distributed in tissues and organs in direct proportion to their lipid content, there being no evidence that lipid was accumulated in the digestive gland in preference to other tissues. 75% of the lipid ingested appeared to have been oxidized within 24 h of feeding.Analysis of organs and tissues showed that the digestive gland was the only potential fat depot in males (lipids 8.89 ± 1.36% of body wet wt), the levels in the rest of the body being only ≈ 1% wet wt). No significant decrease in any lipid concentrations occurred during 18 days starvation of males or 35 days starvation of females, but in males the non-lipid dry matter decreased 6% of the total wet wt (other solids were not measured in the females). It was concluded that this was due mainly to loss of muscle protein and it is suggested that the large abdominal muscle mass of macrurous Reptantia, used principally for emergency escape swimming, could provide a reserve that may be partly metabolized without serious detriment to the animal.The concept that the decapod digestive gland has a key role in general lipid metabolism is critically reviewed. In many Decapoda, digestive gland lipid could provide for only a short period of total starvation, but the lipid may have a principal role in the moulting cycle, with perhaps a secondary function in oogenesis.

The effects of Hematodinium sp.-infection on aspects of the respiratory physiology of the Norway lobster, Nephrops norvegicus (L.)

Article

Dec 1996
J EXP MAR BIOL ECOL

Populations of the Norway lobster Nephrops notvegicus from the west coast of Scotland are infected with a dinofagellate parasite belonging to the genus Hematodinium. The rates of oxygen consumption of infected N. norvegicus were significantly greater than those of uninfected lobsters. This may be attributed partly to the oxygen demands of the very large numbers of parasite cells present in the haemolymph and in the body tissues since the rates of oxygen consumption of the haemolymph of heavily-infected lobsters were approximately 5 times greater than those of uninfected or less heavily infected lobsters. The presence of such large numbers of cells in the haemolymph, which may block haemal sinuses in the gills, appears to compromise oxygen delivery to the tissue of the host since the PO, of the haemolymph of heavily-infected lobsters (PaO, = 2.9910.91 kPa) was significantly lower than that of uninfected lobsters (%O, = 9.4? 1.39 kPa). The oxygen carrying capacity of the haemolymph of heavily-infected lobsters was reduced by approximately 50% compared with that of uninfected animals. In addition, the haemolymph pH was lower and the L-lactate concentration was significantly higher in infected lobsters indicating that these animals resort, in part, to anaerobic metabolism.

Tissue biochemical composition in relation to multiple pawning in wild and pond-reared Penaeus vannamei broodstock

Article

May 2000
AQUACULTURE

The effect of the number of spawnings on several biochemical components of ovary, hepatopancreas, and haemolymph was investigated. Shrimps of two origins were compared; wild-caught and pond-reared spawners. Individually tagged females were sampled at the end of a production period in a commercial hatchery. Females with multiple spawnings had a higher Ž . gonadosomatic index GSI , increased levels of protein in the ovary, and increased levels of Ž . acylglycerides AG and total protein in the hepatopancreas. Wild shrimps had a higher fecundity and higher levels of AG in hepatopancreas, and AG, cholesterol, protein, and glucose in haemolymph. Pond-reared shrimps had a higher hepatosomatic index than wild counterparts. The biochemical composition of the ovary reflected the typical nutrient accumulation associated with maturation. The capacity for multiple spawning could be related to metabolism of energetic lipids that are accumulated in the hepatopancreas, which in turn depends on size and origin of the broodstock. Females with multiple spawning capacity may be adequate for production purposes, although more research is needed to address the possibility of specific metabolic indicators of a multiple spawning capacity without a decline in spawn quality, and to define whether this is an inherited characteristic that can be selected in an improvement program. q 2000 Elsevier Science B.V. All rights reserved.

Maturation of penaeid shrimp: Dietary fatty acids

Article

Mar 1979
J WORLD AQUACULT SOC

Comparisons were made between fatty acid profiles of gonad, digestive gland, and tail muscle samples of immature and mature male and female Penaeid shrimp obtained at sea. The major fatty acids of the lipids from mature ovaries were C20 and C22 polyunsaturated fatty acids. An annelid rich in lipids containing these acids was used as a dietary supplement for shrimp grown in the laboratory, and spawning was achieved with Penaeus setiferus. The possible role of polyunsaturated fatty acids in ovarian maturation is discussed.

Tissue Lipid Content and Fatty Acid Composition of Penaeus monodon Fabricius Broodstock from the Wild

Article

Jun 1990
J WORLD AQUACULT SOC

Tissues (hepatopancreas, muscle, gonad) of wild Penacus mordon females with ovaries in different stages of development and males were analyzed for Upid content and fatty acid composition. Hepatopancreatic tissue had the highest mean levels of lipid at 15.72–25.20% in females and averaged 46.20 ± 1.53% in males. Levels of Lipid in the muscle were low with no marked variation throughout the maturation s-es. Ovarian lipid levels increased significantly at stage II (early maturing ovaries) and remained high through stage IV (fully mature ovaries). Peak lipid level was found at stage III (late maturing ovaries) and coincided with a decline in hepatopancreas lipid. Ovarian and hepatopancreatic lipids declined drastically in spent females. Profiles of fatty acid in the tissues consistently showed the presence of PUFA 204n-6, 20:5n-3 and 22611-3, with high levels in the polar lipid fraction of vitellogenic ovaries. These values were reflected in the male testis and spawned eggs. The finding suggest storage and utilization of lipids for maturation and spawning processes and that the phospholipids were mainly responsible for increases in ovarian lipids. The type of fatty acids present in maturing prawn ovaries is indicative of their importance in reproductive physiology.

Variations de la composition lipidique tissulaire au cours de la vitellogenese chez la crevette Penueus indicus MILNE EDWARDS

Article

Dec 1984
J EXP MAR BIOL ECOL

Robert Galois

Changes in lipid composition are observed in the ovary, the hepatopancreas, the haemolymph and the muscle of the female Penaeus indicus Milne Edwards, during the increase of the gonad-somatic index (GSI). Vitellogenesis is characterized by a large accumulation of lipids in the ovary, which seems to be practically linear when expressed as a function of GSI, if there is no interference from moulting. Phospholipids and triacylglycerols are the major lipid fractions in the ovary, but some classes of minor importance, like wax esters, hydrocarbons, and glyceryl ethers, are also incorporated. These last components may play a rôle in the maturation process.The lipid reserves of the hepatopancreas contribute partially to the formation of vitellin, but direct input of lipids from feeding seems to be preponderant. An intraovarian synthesis of lipids may be possible, but probably restricted, considering the low concentrations of free fatty acids and partial acylglycerols found in the ovary. Phospholipids are the main components involved in the increase in lipid concentration of the haemolymph during vitellogenesis. This increase, and the potential rise in the turnover of circulating lipids, suggest a deep alteration in the lipid metabolism of the females during the breeding period.

Midgut gland as monitor organ for the nutritional value of diets in Penaeus monodon (Decapoda)

Article

Aug 1985
AQUACULTURE

Midgut gland cells of Penaeus monodon postlarvae were investigated by electron microscopy after starvation and refeeding with different diets.Well nourished postlarvae could be starved for 5 days without irreversible detriment. They recovered easily on a good diet. Only R cells were affected by a short starvation period. After 13 days of food deprivation the structures of all cell types were disintegrated. The postlarvae were able to starve for a maximum of 15 days. The most diversified ultrastructure was obtained by refeeding with cod liver oil and 2s (mixed diet). Casein was not well utilized. Sucrose was the poorest diet. The midgut gland of Penaeus monodon seems to be lipid oriented. Only fat was used as storage material; glycogen was lacking.Different ultrastructures were induced in R cells by a given diet after longer starvation periods. The reestablishment of their ultrastructure by means of a definite diet seems to be impossible after a certain period of starvation (point of no return).R cells are very sensitive to different diets. B cells show slight reactions, while F and E cells remain relatively unchanged. This indicates that R cells could be used to monitor the nutritional value of prawn diets in aquaculture.

Effect of highly unsaturated fatty acids, α-tocopherol and ascorbic acid in broodstock diet on egg composition and development of Penaeus indicus

Article

Nov 1995
Comp Biochem Physiol Physiol

Experiments were conducted by feeding Penaeus indicus broodstock with compound diets containing different concentrations of highly unsaturated fatty acids (HUFA), α-tocopherol and ascorbic acid. In the range of dietary HUFA concentration, from 1.4% to 2.5% of dry matter, the HUFA concentration in eggs was maintained at a constant value, 3.8% of dry matter, promoting embryonic development. Eggs with poor HUFA concentration (2%/dry matter) were obtained by feeding broodstock with low dietary HUFA content, resulting in low ability to develop. These results suggest that this concentration is insufficient to sustain membrane development during embryogenesis. The α-tocopherol and ascorbic acid concentrations in broodstock diet affected their concentration in eggs and hatchability. The action of these two vitamins in preventing HUFA oxidation in developing eggs is discussed.

Metabolic rates and energy content of deep-sea benthic decapod crustaceans in the Western Mediterranean Sea

Article

Nov 1998
DEEP-SEA RES PT I

A total of 23 species of deep-sea benthic decapod crustaceans were collected in the Catalan Sea (western Mediterranean) at different depths (200–1250 m) but at the same environmental temperature (13°C) in winter 1992 and winter 1993. Studies on oxygen consumption and energy content were carried out on crustaceans exhibiting two life strategies: nektobenthic species (benthic species with a slight locomotory ability) and benthic-endobenthic species (strictly benthic species). The two deep-sea life styles were associated with two different patterns of metabolic rate and energy content. On the whole, metabolic rates, energy contents, and organic matter contents were higher for the nektobenthic life strategy than for the benthic-endobenthic life strategy. When results were related to depth of maximum abundance of the species consid-ered, it appeared that the nektobenthic species in the upper slope community (200–450 m depth) had a significantly lower energy content (as kJ g-1 of ash-free dry mass) than the nektobenthic species in the middle slope community (550–1250 m depth), but no significant trend was found when the energy content was expressed as a function of wet mass. The benthic-endobenthic species exhibited a significant decrease in metabolic rates, an increase in energy content (when expressed as a function of ash-free dry mass), no significant trend in energy content (as a function of wet mass) and a significant increase in water content with increasing depth over the two depth strata considered (200–450 and 550–1250 m). It was concluded that the lower metabolic rates of deeper-living benthic-endobenthic species, when compared to the shallower-living species, were the result of general locomotory reduction. It is likely that the shallower-living species rely more heavily on visual predation than the deeperliving species (light-limited environment), and this fact is discussed as an explanation of the general metabolic reduction for the benthic-endobenthic Mediterranean species along the depth gradient considered in the present study (200–1250 m).

Aspects of blood physiology and ammonia excretion in Nephrops norvegicus under hypoxia

Article

Dec 1990
Comp Biochem Physiol Physiol

1.1. Circulating haemocyanin, glucose, lactate, and ammonia concentrations and ammonia excretion rates of Nephrops norvegicus were studied in normoxia and in various hypoxia levels for periods up to 3 weeks.2.2. Increases in circulating glucose and lactate took place in oxygen tensions PwO2; = < 30 Torr only, indicating aerobic metabolism down to this oxygen tension.3.3. In moderate hypoxia (half saturation), N. norvegiens synthesised haemocyanin; in more severe hypoxia some haemocyanin catabolism occurred.4.4. Mean normoxic blood ammonia concentration was 130 μM NH+4/1 with large individual variation. Blood ammonia levels decreased with time in both normoxia and hypoxia showing a lowered metabolic rate (activity level) over the experimental period. In short term experiments, blood ammmonia levels decreased in hypoxia.5.5. Mean ammonia excretion rate was O.16μ M NH+4 g/wet wt/hr under normoxia and excretion rate showed a negative, linear relationship to external oxygen tension.

The biochemical composition of eggs from Macrobrachium rosenbergii in relation to embryonic development

Article

Dec 1990
Comp Biochem Physiol B Biochem Mol Biol

1.1. The proximate (water, protein, lipid, mineral ash) and elemental (carbon, nitrogen, phosphorus) composition of eggs of the freshwater prawn Macrobrachium rosenbergii (de Man, 1879) (Crustacea, Decapoda) were determined in relation to embryonic development. Eggs were sampled at four intervals during development, ranging from day 1 (newly spawned) to day 16 (about to hatch).2.2. Egg dry mass, lipid and carbon content all decreased during development as reserves were utilized; at the same time both water and mineral ash content increased. Although the mean content of both nitrogen and protein declined during development these were not statistically significant due to a high variance. Egg phosphorus content remained constant throughout development.3.3. In the lipid fraction triacylgycerol fatty acids provided the major fuel, although phospholipid was also utilized. The most important substrates were 16:0 and 18:1 fatty acids.4.4. There were strong suggestions of an initial increase in egg lipid content during the first 5 days of development, though this was not statistically significant and the source of the extra material is unknown.

Ca balance during moulting in the prawn Aristeus antennatus (Risso, 1816): the role of cuticle calcification in the life cycle of decapod crustaceans

Article

Aug 1989
J EXP MAR BIOL ECOL

The present paper discusses the role of various organs and tissues, carapace, hepatopancreas, gastral epithelium, gastroliths and hemolymph, in the general Ca metabolism of the deep-water penaeid Aristeus antennatus (Rosso, 1816) (Decapoda, Natantia). Data obtained by the authors and data from the literature were considered in terms of the Ca balance and comparative organ function to shed light on possible differences between poorly calcified species (Natantia) and highly calcified species (Reptantia). Two patterns of Ca metabolism related to the life and reproductive strategies of decapod crustaceans are described, one for heavily calcified species (Reptantia) and the other for weakly calcified species (Natantia). Brachyuran species are also discussed but are not associated with either of the metabolic patterns described.

Variation in lipid classes and fatty acid content in tissues of wild Macrobrachium rosenbergii (de Man) females during maturation

Article

Feb 2001
AQUACULTURE

This study describes the variations in total lipid, lipid classes and fatty acids in the midgut gland (MG), ovary, and muscle tissue of wild-caught Macrobrachium rosenbergii to elucidate the importance of these components during sexual maturation. Mature females were captured in the Mae Klong River, Thailand, from July to September 1998, and divided into five groups according to their ovarian development. Total lipid levels in the ovary increased with maturation, but no concomitant decrease in MG lipids was observed. Thus, the lipid requirements of the developing ovary are thought to be more dependent on the immediate ingestion of dietary lipid than on MG reserves. Higher proportions of neutral lipids (NL), mainly triacylglycerols (TG), were observed in both MG and ovary, whereas polar lipids (PL) predominated in muscle. In the ovary, total NL increased significantly along with maturation mainly due to an increase of TG and sterols. Phosphatidylcholine (PC) and phosphatidylethanolamine (PE) formed the bulk of ovarian PL and also increased significantly as maturation progressed. Major fatty acids in both MG and ovary were 14:0, 16:0, 18:0, 18:1n−9, 18:2n−6, 18:3n−3, 20:4n−6, 20:5n−3 and 22:6n−3. Significant increases in the levels of saturated and mono-unsaturated fatty acids were observed in both MG and ovary. The levels of n−3 highly unsaturated fatty acids (HUFA), particularly 20:5n−3, decreased in the MG as ovarian development proceeded. In contrast, an increase in the ovarian contents of n−3 HUFA was detected.

Influence of dietary lipid sources on fecundity, egg hatchability and fatty acid composition of Chinese prawn (Penaeus chinensis) broodstock

Article

Feb 1994
AQUACULTURE

The effect of feeding four semi-purified diets containing different lipid sources (anchovy oil, linseed oil, corn oil and pork lard) on fecundity, egg hatchability and egg and spent gonadal tissue fatty acid composition of Chinese prawn (Penaeus chinensis) broodstock was compared with a fresh clam diet in a 60-day feeding trial. Broodstock prawn fed the diet containing pork lard showed poor fecundity and low egg hatchability. Broodstock fed the diets containing linseed or corn oil showed improved egg production (P<0.05); however, no significant improvement in hatchability was observed. When broodstock were fed the diet containing anchovy oil, both fecundity and egg hatchability were significantly improved (P<0.01).Eggs from broodstock fed anchovy oil as sole dietary lipid had a higher n−3 highly unsaturated fatty acid (HUFA) content (27.6%) compared with those of prawn fed diets containing linseed oil (19.5%), corn oil (14.0%) or pork lard (12.8%). Good correlations between the 20:5n−3 content of the egg lipid and fecundity and between 22:6n−3 content and hatchability were observed. The results suggest that each of these n−3 HUFAs may play different and specific roles in crustacean reproduction and that either or both must be included in the broodstock diet.

Influence of phospholipid and highly unsaturated fatty acids on SR and egg and tissue composition in Penaeus vannamei fed semi-purified diets

Article

Sep 1994
AQUACULTURE

In order to study the influence of dietary phospholipids (PL) and highly unsaturated fatty acids (HUFA) on spawning rate and egg and organ lipid composition of P. vannamei, three batches of eyestalk-ablated spawners were fed semi-purified diets for a period of 45 days. The semi-purified diets differed only in their lipid composition: diet HR had high HUFA and PL concentrations, diet HD had low HUFA and high PL concentrations, while diet PLD had low PL and HUFA concentrations. Control spawners were fed fresh mussel. The spawning rate of the PLD group was one-third of that obtained in the other three groups. Egg numbers per spawning were similar in groups fed the semi-purified diets but significantly inferior (P<0.05) to the number observed in the control group. A large lipid deposition, mainly due to neutral lipid (NL), was observed in the hepatopancreas of animals fed semi-purified diets. The total lipid concentration of eggs did not significantly change with the different diets, but PL concentration of eggs was affected by that of diet. Fatty acid composition of both PL and NL of hepatopancreas, muscle and eggs was widely affected by dietary fatty acid composition. The time course variation of egg fatty acid composition during the feeding period notably showed that the HUFA concentration in eggs of HD and PLD groups fell below 2.5% dry matter after 20 days while it was maintained at up to 4% in eggs of the control group. The ability of eggs containing such a low level of HUFA to sustain lecitotrophic development is discussed with reference to previous studies.

Maturational Changes In The Ovarian Lipid Spectrum Of The Pink Shrimp, Penaeus Duorarum Duorarum (burkenroad)

Article

Nov 1974
Comp Biochem Physiol Physiol

William R. Gehring

1.1. Excised ovaries of the pink shrimp, Penaeus duorarum duorarum Burkenroad, were assigned to one of four sequential developmental stages ranging from Stage 1, undeveloped, to Stage 4, ripe.2.2. Ovarian lipids were extracted and the total lipids determined.3.3. The major phospholipid and neutral lipid classes were separated using thin-layer chromatography.4.4. Total lipids, total neutral lipids, total phospholipids, and the two major neutral lipid fractions, triglycerides and sterols, all followed the same pattern: a significant increase between Stages 1 and 2 and Stages 2 and 3, followed by a decline in Stage 4.5.5. No qualitative changes were detected in the ovarian lipid spectrum as development proceeded.

Nucleic acids as indicators of nutritional condition in the Norway lobster Nephrops norvegicus

Article

Feb 2001

Changes in nucleic acid concentration of the gill, hepatopancreas and abdominal muscle tissue of the Norway lobster Nephrops norvegicus (L.) were examined after 6 and 12 wk of,starvation. Significant decreases in RNA concentration, RNA:protein ratio and RNA:DNA ratio were recorded in abdominal muscle tissue following starvation, but not in gill or hepatopancreas tissue. Samples of abdominal muscle tissue were taken from lobsters from 2 sites in the Clyde Sea area, Scotland. These were south of Ailsa Craig, where N, norvegicus are thought to be nutritionally limited as a result of the high population densities that occur in this area, and south of Little Cumbrae island, where population density is lower. Evidence of nutritional limitation was provided by nucleic acid analysis which showed that the RNA concentration, RNA:protein ratio and RNA:DNA ratio of lobsters from south of Ailsa Craig were significantly lower than in lobsters of equivalent size from south of Little Cumbrae. Further studies demonstrated that animals from each site were capable of obtaining nucleic acid levels similar to those at the other site after a few weeks when exposed to different feeding regimes.

Detection of unconjugated and conjugated steroids in the ovary, eggs, and haemolymph of the decapod crustacean Nephrops norvegicus

Article

Jun 1989

Gas chromatography/mass spectrometry with selected ion monitoring has been employed to examine extracts from the ovary, eggs, and haemolymph of the marine prawn, Nephrops norvegicus, to demonstrate the presence of steroids. Both free and conjugated steroids were isolated by solvent partitioning and chromatography (lipophilic Sephadex, reversed-phase Sep Pak, and normal phase medium-pressure liquid chromatography) and steroidal conjugates were cleaved enzymatically. Steroids were determined as their methyloxime derivatives, trimethylsilyl (TMS) ethers or methyloxime-TMS ethers. All assignments were based on the detection of characteristic ions and cochromatography with the authentic steroid derivatives. 5 alpha-Dihydrotestosterone, testosterone, pregnenolone, and 20 alpha-hydroxypregn-4-en-3-one were detected in unconjugated form in the ovary. The eggs and haemolymph were found to contain unconjugated 17 beta-estradiol. Conjugated 5 alpha-dihydrotestosterone was detected in both the ovary and haemolymph, but no conjugated steroids were found in the eggs.

Endocrine control of reproduction in Decapod Crustacea

Article

Jun 1970

The biosynthesis of the emulsifiers of the crab Cancer pagurus L

Article

Apr 1966
Comp Biochem Physiol

André van den Oord

1.1. The incorporation of acetate-1-C14 into the emulsifiers (fatty acylsarcosyltaurines) occurring in the gastric juice of the crab Cancer pagurus L. was studied. The isotope was incorporated into the fatty acid and sarcosine constituents of the emulsifier, not into the taurine part.2.2. It was concluded that the emulsifiers are of endogenous origin.

Biochemical changes during the reproductive cycle of the deep-sea decapod Nephrops norvegicus on the south coast of Portugal

Abstract

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