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Endocrine control of reproduction in Decapod Crustacea
... confined only to induced maturation and breeding in attempt for seed production of a few commercially important species (Thomas et al., 1974a,b;Muthu & Laxminarayana, 1977;Radhakrishnan & Vijayakumaran, 1984;Muthu et al., 1986;Mohamed & Diwan, 1991, 1994Mohamed et al., 1993;Radhakrishnan et al., 2000;Sunil & Suryanarayanan, 2002;Zacharia & Kakati, 2003;. The neuroendocrine system plays pivotal role in reproductive endocrinology of crustaceans by transducing the environmental stimuli into physiological processes (Adiyodi & Adiyodi, 1970Anilkumar & Adiyodi, 1985;Quackenbush, 1986;Nagabhushanam et al., 1992;Yano, 1992;Yano & Wyban, 1992;Subramoniam, 1999Subramoniam, , 2011Huberman, 2000;Pandey & Kumar, 2006;. Therefore, an attempt has been made to record histomorphological changes occurring in the NSCs of eyestalk, brain and thoracic ganglia of the commercially important giant tiger prawn, Penaeus monodon, in relation to the ovarian maturation along with the histochemical tests on these NSCs to find out chemical nature of the neurosecretion. ...
... stylifera) have also recorded similar changes in the eyestalk of crustaceans in relation to ovarian maturity. It may be likely that B and C cells exert inhibitory influence on ovarian maturation by elaborating maturation-inhibiting hormone (MIH) (Adiyodi & Adiyodi, 1970Anilkumar & Adiyodi, 1985;Pandey & Kumar, 2006;. ...
... Neurosecretory cells (NSC) were described in Crustacea for the first time by Enami (1951) who distinguished three types of cells in the brain of the crab, Sesarma. Reproduction in Crustacea has been hypothesized to be controlled by dual endocrine factorsone inhibitory and other stimulatory both originating from the neuroendocrine centers such as eyestalk ganglia and brain as well as thoracic ganglia (Adiyodi & Adiyodi, 1970Sarojini et al., 1983;Mohamed & Diwan, 1991;Huberman, 2000;Diwan, 2005;Pandey & Kumar, 2006Wilder et al., 2010;Subramoniam, 2011;). Otsu (1963) reported that accumulation of the yolk granules in oocytes was stimulated by repeated implantation of pieces of thoracic ganglion in the immature female crab, Potomon dehanni. ...
... Crustacean eyes function as an important neuroendocrine system, and eyestalk ablation influences gonadal development (21). Eyestalk ablation is commonly used to accelerate maturation and synchronize spawning in shrimp and prawn hatcheries worldwide (22)(23)(24). The maturation of the gonad is regulated by gonad-inhibiting hormone (GIH) secreted from the X-organ-sinus gland (XO-SG) complex of the eyestalk and gonad-stimulating factor (GSF) produced by the brain and thoracic ganglion (22,25). ...
... Eyestalk ablation is commonly used to accelerate maturation and synchronize spawning in shrimp and prawn hatcheries worldwide (22)(23)(24). The maturation of the gonad is regulated by gonad-inhibiting hormone (GIH) secreted from the X-organ-sinus gland (XO-SG) complex of the eyestalk and gonad-stimulating factor (GSF) produced by the brain and thoracic ganglion (22,25). Histological Novel Virus Associated with Sexual Precocity changes with eosinophilic inclusions and in situ hybridization signals in the cells of a variety of tissues in the eyes of IPV-infected M. rosenbergii were observed by comparison with the normal tissues of the prawns without IPS. ...
The iron prawn syndrome (IPS), also described as sexual precocity, results in the reduced size of farmed prawns at harvest and significant economic losses. IPS has been frequently reported in populations of farmed
Macrobrachium rosenbergii
... As it is well known that decapod hepatopancreas serves to absorb nutrients as well as stores reserve materials like glycogen, lipid, calcium etc. The organic reserves from hepatopancreas are known to be cyclically mobilized to the gonads during reproduction as well as to epidermis during moulting (Adiyodi and Adiyodi, 1970).The cell size and dominance of cell type (E, B, F, R) depends on the activity of hepatopancreas in accordance with the gonadal cycle (Franceschini-Vicentini, 2009 and Silva, 2018). Almost similar findings, as observed in present study have been reported in atyid prawn C. weberi (Nagabhushanam et al., 1984), in C. rajadhari (Victor, 1987) and in M. lanchesteri (Narsimha et al., 1981). ...
... The antagonistic relation between ovary and hepatopancreas lipid contents has been observed by various workers like Kumar, (1980) in P. hydrodromus; Varadarajan and Subramoniam, (1982) in C. cilibanaricus and Mohammed and Diwan, 1992 in P. indicus may also be true for antagonistic relation between cell size of hepatopancreas and ovarian development observed in present study (Kale et al., 2011 andRevathi et al., 2012). The carbohydrate content of hepatopancreas have also been reported to fluctuate according to the maturation stage of gonads particularly ovary as observed in P.hydrodromus (Adiyodi and Adiyodi, 1970) in P. hardwickii (Kulkarni and Nagabhushanam, 1979) and in Caridina weberi (Nagabhushanam and Joshi, 1985 and Mohammed and Diwan, 1992) who observed active mobilization of the carbohydrate from hepatopancreas to the ovary during metabolism. The mobilization of organic reserves mainly affect the activity of R and B cells of the hepatopancreas (Gibson andBaker, 1979 andRevathi et al.,(2012) which may be the reason for change in histological architecture of hepatopancreas according to gonadal maturation as observed in present study. ...
The present study was conducted on the experimental animals, Macrobrachium dayanum (Henderson) (Crustacea: Decapoda) to analyze the seasonal changes in reproductive cycle of female, found at different locations in river Gomti (26°55´; 80°59´ E), in and around Lucknow (U.P. India). The reproductive activities were found in cyclic manner in M.dayanum, which breeds continuously throughout the year but with two distinct peaks one major in the month of May-July and one minor in the month of January – Feburary. Five stages of Oogenesis i.e. proliferative, meiotic, previtellogenic, vitellogenic and resorbtion or atretic oocyte phase have been recorded in M. dayanum. Mature ova were noticed in two peaks i.e. major in month of July – August and September and minor in months of February and March. Histoarchitecture of hepatopancreas showed seasonal changes in accordance with the gonadal development. The reproductive cycle of M.dayanum is reported for the first time and very little work is known on the seasonal changes with respect to reproduction and its correlation with hepatopancreas.
... Beruashttps://scofci.stipwunaraha.ac.id/ ruas dan mempunyai aktivitas berganti kulit luar (eksoskeleton) secara periodik seperti kelompok udang pada umumnya (molting). Bagian tubuhnya mengalami modifikasi, sehingga dapat digunakan untuk bergerak, membenamkan diri dalam lumpur, menopang insang (Adiyodi & Adiyodi, 1970). Tubuh bagian luar terbagi atas bagian depan (cephalothorax), bagian belakang (abdomen), dan belakang disebut (uropod) (Mudjiman & Suyanto, 1989). ...
... Kadar pigmen akan berkurang seiring pertumbuhan udang, oleh karena saat mengalami molting sebagian besar pigmen pada kulit ikut terbuang. Keberadaan pigmen memberikan warna putih kemerahan pada tubuh udang (Adiyodi & Adiyodi, 1970;Haliman & Adijaya, 2005). ...
The aim of this research is to know the effect of fertilization and density on survival rate and the absolute growth of post-larvae of shrimp vanname (Litopenaeus vannamei). The study was conducted from 18 August to 5 September 2013 at Oensuli ponds, Kabangka, Muna Regency, Indonesia. The research used animal test of vaname shrimp stadium PL6, fertilizer of Urea and TSP. The study used styrofoam container, 75 cm long, 37 cm wide, and 27 cm high. Research using Factorial RAL, fertilization and density used three levels, three replications, so that the experiment of 27 units. The fertilizer treatment consisted of no-fertilizer (Control), combination Urea 0.5 g/TSP 0.7 g (P2), combination Urea 0.7 g/TSP 0.9 g (P3). The density treatment consists of density 9 ind/container (Control), density 14 ind/container (KP2) and density 19 ind/container (KP3). Parameters observed survival rate (SR) and absolute growth (G). Data analysis using ANOVA (a0,05) with IBM SPSS Statistic 22. The results showed that fertilization and stocking density had a significant effect on survival and post larvae growth of vaname shrimp. The optimum use of 0.7 g/TSP 0.9 g urea per container. The optimum fertilizer composition of growth was Urea 0.5 g/TSP 0.7 g per container. The best survival rate through a combination of Urea 0.7 g/TSP 0.9 g, density 9 ind per container, equivalent Urea 26 kg/TSP 33 kg density 333.000 ind per ha. The best growth through a combination of Urea 0.5 g/TSP 0.7 g, density 9 ind per container or Urea 19 kg/TSP 26 kg, density 333.000 ind per ha.
... In several Uca populations, males are larger than females (Spivak et al. 1991;Litulo 2005a, b, c;Castiglioni et al. , 2010Costa and Soares-Gomes 2009). The size difference between sexes in brachyuran is probably due to males showing a higher growth rate and a longer growth period, while females spend a significant amount of energy in the development of the gonads and to supply the mass of eggs during laying, thus making her somatic growth to diminish (Warner 1967;Adiyodi and Adiyodi 1970;Wenner 1972;Díaz and Conde 1989;Hartnoll 2006). Different mortality rates, migration, spatial and temporal utilization of resources, differences in foraging efficiency, acquisition or assimilation of food, distinct behavior patterns, and higher tolerance of one sex to environmental adversity may be cited as other factors that may influence the differential growth rates between males and females in brachyuran crabs (Giesel 1972;Wolf et al. 1975; Crane 1975; Montague 1980). ...
... The sex-ratio of U. maracoani in size classes showed a standard pattern, as described by Wenner (1972), in which the predomination of males in the larger size classes means that there might be different population growth rate between the sexes. This may be associated with a higher energy requirement for reproduction, because while females are incubating eggs, the somatic growth, which is antagonistic to the reproductive process, ceases, thus slowing their growth (Warner 1967;Adiyodi and Adiyodi 1970;Hartnoll 2006). A similar pattern in the size-class sex-ratio has been observed in this same species by Hirose and Negreiros-Fransozo (2008) in Paraty, state of Rio de Janeiro, southeast Brazil, and other Uca species along the Brazilian coast, as U. rapax Silva et al. 2013), U. burgersi (Benetti et al. 2007), and U. victoriana (Castiglioni et al. 2010). ...
The aim of the present study was to characterize the population dynamics of the fiddler crab Uca maracoani in a mangrove area of the Formoso River, state of Pernambuco, northeast of Brazil. Samplings were performed monthly (April 2009 to March 2010) by one collector during 30 min at the low tide. A total of 1198 individuals (753 males and 445 females) were sampled, and all of them had measured the carapace width (CW), the major cheliped propodus length of males (CPL) and the abdomen width of females (AW). Sex and the ovigerous condition were recorded. Mean size of males (CW) (22.9 ± 6.61 mm) was significantly greater than that of females (20.2 ± 5.2 mm). Morphological sexual maturity estimated for males and females was 15.8 and 13.8 mm of CW, respectively. In the size-frequency distribution of both sexes, the population showed two cohorts, consisting of a juvenile group and an adult group. Sex ratio was diverted in favor of males (1.6:1.0), and males were more frequent in larger size classes. The reproductive period was based on the low rate of ovigerous females found throughout the year, occurring from June to August 2009. The recruitment was continuous throughout the year, but more intense during spring. Results of the present study are the first recorded from the state of Pernambuco and not only enabled a better comprehension of the population biology of U. maracoani along its latitudinal distribution, but also allowed to observe the population stability in the Formoso River mangrove.
... presenta células especializadas para el almacenaje, digestión y absorción de compuestos orgánicos e inorgánicos obtenidos de los alimentos; c) se destaca por el papel que cumple como centro de almacenamiento de reservas energéticas, principalmente lípidos, y en menor proporción carbohidratos y proteínas; e) es responsable del 85% de la asimilación de nutrientes en cangrejos decápodos; mucho más que el intestino medio, el cual absorbe apenas entre 5-10% de los nutrientes (Adiyodi & Adiyodi, 1970;Gibson & Baker, 1979;Herreid & Full, 1988). ...
... El peso de las gónadas se ha interpretado como un reflejo de la actividad gonadal y como una expresión de la preparación para el desove en hembras (De Vlaming et al., 1983;Kyomo, 1988;Kennish, 1996Kennish, , 1997Kyomo, 2000). Es aceptado ampliamente que en el hepatopáncreas de los crustáceos ocurre una acumulación cíclica de reservas orgánicas (Adiyodi & Adiyodi, 1970). Estas reservas son usadas para la formación del nuevo exoesqueleto durante el periodo de muda (Adiyodi, 1969) y también son transferidas hacia las gónadas para la producción de gametos con fines reproductivos (Pillay & Nair, 1973;Kyomo, 1988;Yamaguchi, 2001;Lee & Kwo, 2002;Dutra et al., 2008). ...
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.
... This gland secretes a hormone involved in the differentiation of primary, secondary and behavioral aspects of the male (King, 1964). According to Adiyodi & Adiyodi (1970), this hormone is also involved in the differentiation of testicles and sperm ducts, and in the stimulation of spermatogenesis. In malacostraceans, the gland is generally located in the subterminal part of the vas deferens (King, 1964;Charniaux-Cotton et al., 1966;Ginsburger-Vogel, 1983;Taketomi, 1986;Lima, 1995;Fowler & Leonard, 1999). ...
... Cross-sections of the vas deferens show the andronic gland of both U. cordatus and G. cruentata as a sinuous string of irregularly shaped cells, matching descriptions of brachyurans by Adiyodi & Adiyodi (1970). According to these authors, the cell strings of the androgenic gland may be sinuous or convoluted. ...
The androgenic gland has been shown to control sexual differentiation in decapods by secreting a hormone capable of determining the primary, secondary and behavioral aspects of the male. The objective of this paper was to make a histological and histochemical description of the androgenic gland of two mangrove crab species, Ucides cordatus and Goniopsis cruentata, at the Ceará River estuary, Brazil, based on a forty-specimen sample of each species. Fragments of the vas deferens were preserved in Bouin's solution for 24 hours and submitted to routine histological analyses. The androgenic gland of the two species was observed microscopically to lie along the vas deferens, beginning at the location where the latter penetrates the musculature of the endofragmal skeleton. The gland consists of a sinuous string of irregularly shaped cells overlying a thick, circular and striated muscle layer, not restricted to the subterminal region. The morphology of the androgenic gland of U. cordatus and G. cruentata is similar, matching the general descriptions published for other decapod species. A glândula androgênica tem sido mostrada como controladora da diferenciação sexual nos decápodes, deter minando a diferenciação das características primárias, secundárias e comportamentais dos machos. O objetivo deste trabalho foi realizar uma descrição histológica e histoquímica da glândula androgênica de Ucides cordatus e Goniopsis cruentata. Quarenta indivíduos de cada espécie foram coletados no estuário de Rio Ceará. Fragmentos do vaso deferente foram fi xados em mistura de Bouin por um período de 24 horas e submetidos à rotina histológica padrão. A glândula androgênica dos caranguejos estudados foi visualizada, microscopicamente, ladeando o vaso deferente, iniciando na região onde este órgão penetra na musculatura do esqueleto endofragmal. Esta glândula apresenta-se como um cordão sinuoso de células de formato irregular apoiado numa espessa camada muscular circular estriada não estando restrita à região subterminal. De modo geral, a morfologia da glândula androgênica dos caranguejos Ucides cordatus e Goniopsis cruentata é semelhante, seguindo o padrão descrito para outras espécies de Decapoda.
... The muscle of the Fresh water crab Spiralothelphusa hydrodroma is highly rich in protein. Due to the environmental stimulations, the neuroendocrine organs produce significant alterations in physiology of crustaceans (Adiyodi and Adiyodi, 1970). The effect of eyestalk ablation reduces the GIH and causes accelerated growth of ovary. ...
... arine water prawn Penaeus indicus are available in the various coast of india in different seasons. The environmental stimuli induces the neuroendocrine system of crustaceans that plays an important role in physiological changes (Adiyodi and Adiyodi, 1970;Anilkumar and Adiyodi, 1985). ...
... The reproductive physiology of decapods is directly affected by air and water temperature, as they promote the growth of gonadal tissues [124][125][126]. In addition, the average diurnal interval (Hydro2), which analyzes the fluctuation of the maximum and minimum water temperature throughout the year, was important in the construction of the models of M. jelskii and M. amazonicum. ...
Biological invasions pose significant challenges in the Anthropocene, impacting ecosystem
biodiversity and functioning. Ecological Niche Modeling is widely used to evaluate potential areas at
risk of invasions, aiding in the prevention of invasive-species expansion and guiding conservation
efforts in freshwater ecosystems. The main objectives of this study were to model the ecological niche
and evaluate remaining suitable habitat areas for the occurrence of five potentially invasive species
of freshwater decapods in South America: Dilocarcinus pagei, Macrobrachium amazonicum, M. jelskii,
M. rosenbergii, and Procambarus clarkii. Occurrence data from the Global Biodiversity Information
Facility were complemented with a literature systematic review. Variables used in the models were
obtained from the Worldclim and EarthEv databases. Ecological Niche Modeling was performed
using the Biomod2 and sdm package algorithms. Our results indicated a suitable area of up to 11%
of South America. Model evaluations yielded favorable TSS and AUC values (>0.7 and >0.8). The
suitable areas projected for South America included several hydrographic basins and Protected Areas.
The information generated in our study can help identifying areas susceptible to decapod invasion in
South America and support local management and decisions.
... This result also supports the hypothesis of multiple spawning. Assuming that in the case of multiple spawning, it is expected that the number of eggs would tend to decrease during later spawning, resulting in a wide variation in the number of eggs produced by females in each size class (Adiyodi and Adiyodi 1970;Teixeira et al. 2017). While these reproductive patterns are not well understood in U. maracoani, the findings of the present study provide an important preliminary insight into this phenomenon. ...
In this study, aspects of the reproductive biology of a Uca maracoani population from northern Brazil were examined. Ovigerous females monthly captured from December 2013 to November 2015 were measured and dissected to count, collect morphometric data, and classify the eggs. Ovigerous females were encountered throughout the two-year period but were absent during the months with the highest rainfall and lowest salinity, which indicates a seasonal–continuous reproductive pattern. The fecundity varied from of 12,233 to 85,000 eggs per female, and mean was 36,840 ± 3,361 eggs. The egg size increased progressively and significantly over the course of embryonic development. We found a direct relationship between the size of the females and their fecundity, and a clear trend was seen in which the larger females produced more eggs with larger sizes, which increased less in size during embryonic development. The presence of early- and late-stage eggs together in the same ovigerous mass in a considerable number of the ovigerous females suggests multiple spawning. The fecundity of U. maracoani is greater than that of other Atlantic fiddler crab species, and its reproductive strategy ensures its survival in the estuaries of the Amazon coast, which are subject to considerable fluctuations in salinity.
... Cette neurosécrétion pourrait aussi être une des cibles des Wolbachia féminisantes. L'étude des sacculines chez les crabes a d'ailleurs révélé que les différents centres neurosécréteurs sont la cible du parasite féminisant (Rubiliani and Payen, 1979), le contact entre ce dernier et les GA étant facultatif (Rubiliani-Durozoi et al., 1980 (Kegel et al., 1989;Fanjul-Moles, 2006)) et une sous-famille de neuropeptides régulant notamment la mue via la MIH (Molt Inhibiting Hormone) (Webster and Keller, 1986), la synthèse de méthylfarnésoate via la MOIH (Mandibular Organ Inhibiting Hormone) (Wainwright et al., 1996) et la fonction sexuelle via la GIH (Gonad Inhibiting Hormone) (Adiyodi and Adiyodi, 1970;Lacombe et al., 1999;Chan et al., 2003). Comme évoqué précédemment au sujet de Wolbachia, les neurosécrétions semblent en effet impliquées dans la physiologie sexuelle chez les Malacostracés (Legrand et al., 1982). ...
La différenciation sexuelle des Isopodes dépend d'une hormone sexuelle protéique, l'hormone androgène (HA), caractéristique des Malacostracés. Cet Insulin-Like Peptide suffit à induire par sa présence la différenciation mâle de ces Crustacés. Nous avons identifié in silico le transporteur circulant de l'HA, l'IGFBP-rP1, chez de nombreuses espèces d'Isopodes ainsi qu'à l'échelle des Crustacés. De la même façon, nous avons identifié deux récepteurs transmembranaires, l'IR1 et l'IR2, issus d'une duplication de gène spécifique des Malacostracés. Les patrons d'expression de ces gènes ont été étudiés sur notre espèce modèle, Armadillidium vulgare. Av-IGFBP-rP1 et Av-IR1 sont exprimés de manière ubiquiste et tout au long du développement. Av-IR2 est aussi exprimé à chaque stade de la différenciation mais ce transcrit est quasi-spécifique des glandes androgènes et ovaires. Une approche par ARNi a confirmé l'implication de ces trois protéines dans la voie de signalisation de l'HA. En effet, l'inhibition de l'HA, Av-IGFBP-rP1 et Av-IR1 provoquent l'hypertrophie des glandes androgènes, suggérant leur implication dans une boucle de rétro-contrôle de l'HA. L'inhibition de Av-IR2 semble seulement provoquer la différenciation d'ouvertures génitales femelles. Ces phénotypes sont comparables à ceux des intersexués mâles induits par la bactérie féminisante endogène Wolbachia. Nous montrons cependant que la bactérie altère seulement l'expression de l'HA et pas celle des récepteurs. Enfin, nous avons testé l'effet du bisphénol A mais nous n'observons pas d'altération de la différenciation sexuelle des larves lors d'expositions à ce perturbateur endocrinien exogène.
... DTFS can be thought as a trait indirectly measuring maturation and ovulation rate, which does depend on hormonal control of vitellogenesis and ovulation. Ovulation in shrimp depends on gonad development, which in turn is controlled by the gonadinhibiting hormone (GIH) among others (Adiyodi and Adiyodi, 1970;Fingerman, 1987). Therefore, it can be postulated that this hormone might also had the largest heritability of all evaluated traits. ...
El factor más limitante del crecimiento de la camaronicultura es la
insuficiencia en cantidad y calidad de postlarvas, por lo cual las
investigaciones sobre la reproducción en cautiverio se ha enfocado hacia la
identificación/optimización de técnicas y factores (ambientales,
nutricionales bioquímicos-fisiológicos y endocrinos) que están
involucrados en el proceso de maduración apareamiento y desove, con el
fin de lograr un optimo desempeño de los reproductores con la obtención
de larvas de calidad. Con base en los resultados obtenidos en algunas
especies de peces como la trucha, recientemente se ha enfatizado que la
aplicación de programas de mejoramiento genético en camarón, basados
sobre conocimientos fisiológicos y genéticos de caracteres productivos y
reproductivos que contribuirán a incrementar la producción con la
obtención de larvas de calidad. Sin embargo actualmente los programas de
mejoramiento genético que existen están basados principalmente en
caracteres del crecimiento y no en caracteres reproductivos, esto se debe
principalmente a que la base genética y la existencia de variabilidad
genética para esos caracteres no ha sido evaluada en camarón, a pesar de
que la optimización de la reproducción es tan importante como el
crecimiento.
... Santiago (1977) stated that crustacean eyestalks are known to be the distribution centre of the vitellogenin and Moult Inhibiting Hormones (MIH). Adiyodi and Adiyodi (1970) have shown that precocious moulting or gonad development produced by eyestalk removal depends on the relative interaction of other ambient environmental factors and age of the treated animal. ...
Many crustacean species including mud crab, genus Scylla are incapable of natural maturation under captivity, thus putting high pressure on the wild catch. Therefore, to increase the availability of mature broodstocks in captivity, this study determined the effect of Eyestalk Ablation (EA) and Methyl Farnesoate (MF) administration on ovarian maturation stages of the orange mud crab, Scylla olivacea. The study was conducted using a control group (T1) consisting of 95% alcohol (widely used as a chemical solvent), and three treatment groups consisting of: 5 µl/g oral administrated MF in the diet (T2), EA (T3) and a combination of both treatments of MF and EA (T4). The highest percentage of ovarian maturation Stage 4 was found in the T4 treatment (20.8%) compared to the other treatments which were T1 (0%), T2 (8.33%) and T3 (12.5%). Ovarian development of the treated groups (T2, T3, and T4) was significantly different compared to the control group (T1) (p < 0.05). However, there was no significant difference observed in the mean Gonadosomatic Index (GSI) in orally administrated MF (T2) compared to the EA group (T3) (p > 0.05), but it was significantly different when compared to the combination group of MF and EA (T4) (p < 0.05). It can be concluded that the combination method of oral administration of MF through diet and EA (T4) is the best technique for producing mature ovaries.
... The well-known reproductive regulatory hormones in crustaceans are gonad-inhibiting hormone/Vitellogenesis inhibiting hormone (GIH/VIH) synthesized and secreted from the X-organ-sinus gland complex located in eyestalk neural tissue [5,6] gonad-stimulating hormone (GSH) synthesized and released from brain and thoracic ganglion [7][8][9][10][11] and a sesquiterpene hormone methyl farnesoate a secretary product of mandibular organ (MO) [12][13][14][15]. In specific MF is a positive regulator for reproduction and is negatively controlled by mandibular organ inhibiting hormone (MOIH) [2,[16][17][18][19] which suppressed the synthesis and release of MF from MO. ...
... In females, reproduction is regulated by two neurohormones, i.e. gonad-inhibiting hormone (GIH) and gonad stimulating hormone (GSH). GIH is synthesized and secreted from the sinus gland of eyestalk which inhibits the gonad maturation (6,7). GSH, which secreted from the brain and thoracic ganglion, stimulates gonad maturation (8)(9)(10). ...
Background: Crustacean reproduction is under the control of various peptide and steroid hormones including vertebrate steroids. In the present study, we examined the role of vertebrate steroids, progesterone and 17β-estradiol in the regulation of testicular development in the crab Oziotelphusa senex senex. Methods: The crabs were divided into eight groups, first group served as initial control and second group served as concurrent control received vehicle. Third, fourth and fifth groups were injected with progesterone and six, seven and eight groups were injected with 17β-estradiol each at the doses of 10-6 , 10-7 and 10-8 mole/crab respectively on 1 st , 7 th , 14 th and 21 st day of the experiment. After 28 days of the experiment the crabs were sacrificed on 30 th day and testis was collected and measured testicular indices and testicular follicle diameter. Results: The mean testicular indices and testicular follicle diameter were increased significantly (p<0.0001) in progesterone and 17β-estradiol injected crabs in a dose dependent manner when compared with controls. In the histological studies, the testes of controls and concurrent controls were in immature stage only. Whereas testes of vertebrate steroids injected were in mature stage. Conclusion: The results of the present study provide evidence that vertebrate steroids, progesterone and 17β-estradiol are involved in the regulation of testicular development and spermatogenesis in crabs.
... Uma base abdominal mais larga (marcos 1 e 9) pode ser justificada pela disponibilidade de parte de suas energias para a reprodução e durante o tempo em que as fêmeas incubam os ovos nos pleópodos (Adiyodi & AdiyodI, 1970;Hartnoll, 1985), comportamento característico da maioria dos decápodos límnicos (López-Greco et al., 2004). Entretanto, o estreitamento da porção dos marcos 3 e 7 apresentada no presente trabalho não foi relatada por outros autores em seus estudos. ...
RESUMO: Nos crustáceos, os estudos de dimorfismo sexual utilizando morfometria geométrica são particularmente adequados, devido à facilidade e acurácia na identificação dos marcos anatômicos. O objetivo do presente estudo foi identificar a existência de dimorfismo sexual e etário do caranguejo de água doce Goyazana castelnaui (H. Milne-Edwards, 1853), excetuando-se o dimorfismo do pléon, por tratar-se de um aspecto intrínseco aos Brachyura. Foram determinados 10 marcos anatômicos para vista ventral e 11 para a vista dorsal. Foi gerada uma matriz de covariância contendo fatores referentes aos sexos e aos grupos etários de cada sexo, sendo as imagens consideradas simétricas. A Análise de Variáveis Canônicas (CVA) e a análise discriminante (DA) foram realizadas com 999 permutações e as comparações foram feitas com base no teste de Hotteling (T2) da distância de Procrustes. Para a vista ventral não foi encontrada nenhuma variação na forma entre jovens e adultos de fêmeas e machos (p= 0,4548; p= 0,131, respectivamente) com base na distância de Procrustes. Na vista dorsal, foi observada uma separação entre as fêmeas adultas e os demais grupos, indicando uma modificação notória do volume do cefalotórax para alocação das gônadas.
... Aspects of fecundity, size at first maturity, reproductive output and spawning frequency are of great importance in establishing the reproductive potential of a species and constitute essential input parameters in determining yield or fecundity per recruit (Caddy, 1977;Somerton, 1980;Campbell, 1985). These parameters also provide insights into the reproductive strategy of an individual species (Adiyodi & Adiyodi, 1970). Reproductive investments vary considerably in marine invertebrates, as does reproduct- ive output, due to environmental factors like temperature, food availability, competition etc. ( Clarke et al., 1991). ...
Details on size at first maturity, embryo number and size, brood chamber volume and reproductive output of deep-sea armoured shrimp, Glyphocrangon investigatoris caught off the south-east coast of India by using EXPO trawl from 633 m depth in FORV ‘Sagar Sampada’ are reported here. Eighty-four female shrimps ranging from 17.29–36.31 mm carapace length and 2.28–16.54 g weight formed 7.73% of total catch, 30% of which was constituted by embryo-bearing females. Regression of weight on carapace length revealed negatively allometric growth (r ² = 0.85, P < 0.01). The size at first maturity was estimated as 19.96 mm. The embryo number ranged from 55 to 233 with a mean of 120.24 ± 34 embryos and showed a positive correlation to body size. Embryo diameter varied between 1.0 to 3.34 mm and more than 50% of embryos constituted the 2.0–2.5 mm size class. Brood chamber volume and percentage frequency of embryo stage development revealed a linear relationship with carapace length. Based on dry weight, mean reproductive output was estimated to be 0.16. The female armoured shrimps showed a high reproductive investment evidenced from few, large, yolky embryos, indicating their deep-sea adaptation.
... Ovarian maturation of crustacean is controlled by both internal and external causes. The external cause includes temperature, photoperiod, food availability and salinity; they all have great influence on reproductive performance [1] . Photoperiodism is known to affect the behavior and physiology of crustacean [2] . ...
... Ovarian maturation of crustacean is controlled by both internal and external causes. The external cause includes temperature, photoperiod, food availability and salinity; they all have great influence on reproductive performance [1] . Photoperiodism is known to affect the behavior and physiology of crustacean [2] . ...
The effect of photoperiodism on the ovarian maturation and ovarian indices of female freshwater prawn Macrobrachium lamarrei lamarrei {H. M. Edwards, 1837} was investigated in the laboratory over a period of 28 days. 90 healthy specimens of M. lamarrei lamarrei were taken with uniform weight (0.286-0.325gm) and length (35-40 mm). The experimental prawns were divided into three groups Viz, control, continuous dark and continuous light. The ovarian maturation was assessed by microscopic and histological observations. G.S.I (ovarian indices) of all the 3 groups has been calculated. The result from this study revealed that in continuous dark the ovaries are in more developed conditions as compare to control and continuous light. The GSI revealed after the study shows marked difference as that of control group. Therefore, it was concluded that complete darkness is useful to accelerate ovarian maturation in M. lamarrei lamarrei.
... The well-known reproductive regulatory hormones in crustaceans are gonad-inhibiting hormone/Vitellogenesis inhibiting hormone (GIH/VIH) synthesized and secreted from the X-organ-sinus gland complex located in eyestalk neural tissue [5,6] gonad-stimulating hormone (GSH) synthesized and released from brain and thoracic ganglion [7][8][9][10][11] and a sesquiterpene hormone methyl farnesoate a secretary product of mandibular organ (MO) [12][13][14][15]. In specific MF is a positive regulator for reproduction and is negatively controlled by mandibular organ inhibiting hormone (MOIH) [2,[16][17][18][19] which suppressed the synthesis and release of MF from MO. ...
The present study focused to elucidate the effect of methyl farnesoate (MF) on ovarian development and maturation in the freshwater giant prawn, Macrobrachium rosenbergii. Control, eyestalk ablated (ESX) and MF injected prawns were maintained during the experimentation and observed significant (p<0.001) increase in the mean ovarian index, oocyte diameter and ovarian vitellogenin levels in both eyestalk ablated and methyl farnesoate administered prawns when compared with controls. All the MF injected animals are in vitellogenic stage III, whereas ESX animals were showed all the reproductive stages at 30th day of experiment. The levels of protein and lipid in the ovary were also measured. The total protein and lipid content levels were also significantly increased in eyestalk ablated (145.07% and 72.05% respectively) and MF injected animals (315.21% and 118.39% respectively) than the controls. The outcome of the present study clearly suggests that MF stimulates the reproduction in female prawns than the conventional ESX method.
... The hepatopancreas synthesizes and releases serum vitellogenin, which is immunologically identical to lipovitellin, the major high-density lipoprotein in the fully-developed ovary (Paulus and Laufer, 1987). Reproductive processes in the brachyurans, including vitellogenesis, are governed by neuralhormonal mechanisms (Adiyodi and Adiyodi, 1970). Therefore, in addition to the oocytes, the cells in the hepatopancreas that synthesize vitellogenin are potential targets for hormonal factors regulating reproduction (Paulus and Laufer, 1987). ...
Female red swamp crayfish, Procambarus clarkii, were exposed for 21 days in the laboratory to different dissolved concentrations of zinc (1000 µg L-1 and 3000 µg L-1) and cadmium (10 µg L-1 and 30 µg L-1), determined in the Guadiamar River after the Aznalcóllar mining spill (SW Spain). Female gonadosomatic and hepatosomatic indexes were analyzed at the end of the bioassay, and a general decrease in the gonadosomatic index and increase in the hepatosomatic index were observed in individuals at the same maturation stage, exposed to increasing heavy metal concentrations. Only the decrease in the gonadosomatic index values was significant at the highest zinc concentration. Decreases in gonadosomatic indexes were associated with reduced fecundity.
... Assuming that in the case of multiple spawning, the number of eggs tends to decrease in the later spawning, the wide variation in the number of eggs produced and the high standard deviation for the fecundity of females in each size class found for this species could be related to multiple spawning. As Adiyodi and Adiyodi (1970) suggested, the antagonism in use of energy resources between the processes of molting and gamete production may be a factor that increases the variability in fertility. Bryant and Hartnoll (1995) assumed that the first egg mass produced by a female immediately after the puberty molt would be smaller than egg masses in subsequent spawning, because the female would have expended large amounts of energy during molting and growth. ...
The variation in reproductive investment (RI) and the hypothesis of multiple spawning were evaluated in the redfinger rubble crab Eriphia gonagra (Fabricius, 1781). The gonads and embryos showed synchronous development, and fecundity and RI varied widely among females of the same size class. The mean RI value recorded was 11.31%, with no significant differences among the means for different size classes. The allometric analysis of fecundity indicated RI decrease while body size increase, but we suggested that this occurs due to size overestimation where the largest width of carapace was used as body size reference in these analyzes. In addition, we found an isometric relationship for “female weight vs. egg number”, and also for “female weight vs. egg weight”, indicating that RI increased proportionally with size of females. Relatively high frequencies both of smaller females with rudimentary gonads, and of larger females with developed gonads were observed. This indicates that larger females take place more frequently in the population reproductive output over time. This difference could not be observed by means of RI analyses of captured and fixed crabs, for which only one stage of gonad development and/or one spawning is usually recorded.
... GIH/VIH is the major eyestalk neuropeptide that inhibits the ovarian activities in Crustacea. A gonad stimulatory hormone (GSH), secreted from the brain and thoracic ganglia, was first proposed to act in antagonism with the GIH (Adiyodi and Adiyodi, 1970). This concept was in vogue, until the other gonad stimulatory hormones from non-neural sources were discovered. ...
Hormonal control of oocyte maturation in crustaceans is reviewed. The bihormonal control of egg maturation is accomplished by the inhibitory neuropeptides originating in the X-organ/sinus gland neurosecretory system and a host of stimulatory hormonal factors secreted from various sources. Among the gonad stimulatory hormones, steroids play a pivotal role in the control of molting and reproduction in crustaceans. Whereas ecdysteroids control molting, vertebrate sex steroids such as estrogen and progesterone seem to control vitellogenic activities. A protocol to stimulate vitellogenesis and egg maturation in the commercially important marine and fresh water shrimps by combining eyestalk ablation with sex steroid hormone treatment is proposed.
... At this time, the causes that trigger growth retardation are remain to be explored. However, since the nervous system of shrimp, especially the optic lobe has found to control not only in motor and sensory, but also neurohormonal functions, such as molting activity by cells of the X-organ in eyestalk optic lobe, which is directly related to growth and body colors of shrimps and other crustaceans (28). The finding that MSGS P. monodon was infected by putative virus in its eyestalk optic lobe and other neural tissues also suggests a potential interference to their neurohormonal regulating system, and possibly resulting in abnormal body color and/or stunt growth. ...
To determine the cause of monodon slow growth syndrome (MSGS) in the black tiger shrimp Penaeus monodon, re-infection experiment was carried out by injection of bacterial free lymphoid organ extracts (LOE) from two commercial shrimp species into healthy juvenile P. monodon. The shrimps of which LOE were obtained, were MSGS P. monodon, specific pathogen-free (SPF) white Pacific shrimp P. vannamei that were co-cultured with MSGS P. monodon, SPF P. vannamei that were mono-cultured, and P. monodon that had normal growth rate. Both groups of the P. vannamei, from which LOE were taken, did not have growth retardation. Four and a half months post-injection, P. monodon groups that received LOE from MSGS P. monodon and P. vannamei that were co-cultured with MSGS P. monodon had clinical manifestations of MSGS, i.e., growth retardation, size difference and increased body color. Under light microscopy (LM), the lymphoid organ of the naturally occurred MSGS P. monodon contained several spheroids with inclusion bodies of different size and colors in the spheroidal cells and similar features were observed in the gills. Under transmission electron microscopy (TEM), numerous icosahedral virus-like particles at 25 nm in diameter, and without envelope, were observed in association with the inclusion bodies. Besides the lymphoid organ spheroids and the gills, the abdominal muscle, eyestalk optic lobe, brains, and the ventral nerve cord were also examined. All the tissues examined, especially in the neural tissues, contained the virus-like particles. The LM and TEM features of the experimentally induced MSGS P. monodon were also similar to those of the naturally infected shrimp, suggesting that the 25 nm agent may be a causative virus for MSGS. The virus was also observed under TEM in P. indicus and Macrobrachium rosenbergii that were co-cultured with MSGS P. monodon, although growth retardation of these two species has not been reported. This study showed another example of horizontal transmission of virus from one to the next shrimp species, in which the original G. ANANTASOMBOON et al. 90 species that were infected by the virus had no clinical manifestation but the species that received the virus showed morbidity.
... The higher concentration of salts in the water helps the juvenile integument to harden within a short time period, considering that juveniles have shorter intermolt periods than adults (Vogt, 2012). Studies on crustaceans have shown that difficulties in acquiring calcium and organic supplements to harden a new exoskeleton may increase the mortality rate (Adiyodi & Adiyodi, 1970;Lima & Oshiro, 2006). ...
The seabob shrimp Xiphopenaeus kroyeri ranks third in commercial importance among fisheries in southeastern Brazil. An important management question is whether the same offseason can be applied to different regions. The population dynamics of the seabob shrimp was compared in two regions of southeastern Brazil: Macaé, state of Rio de Janeiro and Ubatuba, state of São Paulo. All demographic categories of shrimp in the Macaé region were larger than those in the Ubatuba region. Lower temperatures and greater longevities in the Macaé region may account for this difference in size from Ubatuba. In Macaé, number of reproductive females and juveniles correlated with organic-matter content. In Ubatuba, only chlorophyll-a showed a correlation with reproductive females. The reproductive period and recruitment were correlated in both populations. The difference in environmental factors between these regions, resulting of the Cabo Frio upwelling, although they are located close together, directly influences the population dynamics of X. kroyeri. The Cabo Frio upwelling may be acting as a physical barrier, preventing gene flow and differentiating the seabob shrimp stocks in the two regions. These data suggest that different offseason periods for different regions could increase the sustainability of shrimp harvesting along the Brazilian coast.
... hydrodromoas. However, it is not clear whether the eyestalk principle/s exPgrt influence seminal plasrna synthesis directly or via the ar,drogenic gland (AGFas AG is larown to be under the control of GIH (Adiyodi & Adiyodi, 1970). Such influence of male sex hormones on Semen production are known to exist in vertebrates (Mann & Lutwak-Marur, 1981). ...
... Removal of eyestalks abolishes the daily rhythm and it is very clear that light, amongst other environmental factors, has an impact on timing of reproduction and the moult cycle via a complex network of neuropeptides and the sinus gland complex (Nagaraju, 2011). Although hormones and factors deriving from the eyestalk are known to control growth, moulting, heart rate, metabolic rate, metabolism of sugars and proteins, water balance, pigment movements and reproduction (Adiyodi & Adiyodi, 1970), to date the details of the mechanisms of reproductive regulation and moult cycle progression remain hazy. Based on examinations of the eyes of mesopelagic species, Gaten, Shelton & Herring (1992) suggest that the nebenauge is directed at the region of highest light intensity and may have a stabilising role or have something to do with the regulation of diurnal vertical migrations observed in such species. ...
Most caridean decapods have compound eyes of the reflecting superposition kind and some additionally possess an accessory eye-like organ of unknown function also referred to as the nebenauge. We examined 308 caridean genera to assess the general morphology of the eye, rostrum length, eye diameter and the presence or absence and, when present, the diameter of the nebenauge. We have attempted to relate these data to ecological and taxonomic considerations. We consider there to be 6 distinct eye types based on the margin between the eyestalk and cornea. The presence of nebenaugen appears to be generally linked to an active lifestyle, as evidenced by the fact that species that have nebenaugen tend to have larger eyes and are more likely to have a distinct rostrum. We suggest that the inconsistencies in its presence/absence under both systematic and ecological lenses may indicate that when present it has various roles relating to behavioural and physiological rhythms.
... In brachyurans, reproduction and moulting are programmed as antagonistic events (Adiyodi & Adiyodi, 1970); the intermoult period chiefly devoted to reproduction, whereas the premoult and postmoult for somatic growth (Adiyodi, 1988). The present study revealed that the first half of the ...
The present study examined the seasonal and moult related changes in spermatogenic process of the freshwater crab Travancoriana schirnerae using histo-logical methods. The annual spermatogenic process revived during March/April with gonadal proliferation and division of spermatocytes and attained its peak in May/June with acini containing mature sperms. A decline in activity was detectable during July/August, that corresponded to the mating season with inactive and resting secondary spermatocytes and spermatozoa. From September to February, the testis remained inactive, enclosing pycnotic gonia, spermatocytes and degenerating residual sperms. The premoult and postmoult testes exhibited inactivity with pycnotic gonia, spermatocytes and residual sperms whereas the intermoult testes appeared active with gonial proliferation, meiotic spermatocytes and mature spermatozoa. It has also been observed that there exists an antagonism between growth and reproduction in this species.
Histomorphology of the neurosecretory cells of eyestalk, brain and thoracic ganglia of Macrobrachium rosenbergii were recorded. There were five types of neurosecretory cells (NSCs) in eyestalk having size range of 5 - 35 um, shape varied from round to oval. The cells were distributed in medulla externa, medulla interna and medulla terminalis. Sinus gland measuring 30-35 um was located in medulla interna. Axonal terminals of the neurosecretory cells were found to terminate in this structure. Brain and thoracic ganglia possessed five types of neurosecretory cells such as giant neuron (>80 um), A (60-80 um), B (40-60 um), C (20-40 um) and D (<20 um). They were seen arranged in several groups in different parts of brain. While B, C and D cells were localized in anterior region, giant neurons and A cells dominated in posterior region. In lateral regions A, B, C and D cells were distributed. The thoracic ganglia could be divided into anterior, middle and posterior regions. NSCs were distributed in anterior and posterior portions but were lacking in middle part. A and B cells were present in anterior regions followed by C and D cells. In posterior region, giant neurons and A cells were present. Histochemical tests demonstrated the neurosecretory cells of the prawn to be strongly positive for acid fuchsin, aldehyde fuchsin and paraldehyde fuchsin and also exhibited feeble reaction to Sudan black B and periodic acid-Schiff (PAS) reagent.
This datasheet on Litopenaeus vannamei covers Identity, Overview, Associated Diseases, Pests or Pathogens, Distribution, Dispersal, Biology & Ecology, Environmental Requirements, Natural Enemies, Impacts, Uses, Management, Genetics and Breeding, Economics, Further Information.
This study was carried out to determine the reproductive characteristic of Liocarcinus depurator (Crustacea: Decapod: Brachyura) captured from South-eastern Black Sea between
December 2012 and November 2013. The samples were taken at depth of 0-30+ m by using 2 meters width beam trawl in Iyidere, Cayeli and the Centre Stations. The maximum GSI values were observed between August and November in females and in March in males. 50% sexual maturity length was calculated as 32.28 mm (KG) for males and 28.19 mm (KG) for females. The results of this study will be an important knowledge for further studies on the L. depurator species.
Pubertal molt is a vital stage in the cultivation of mature female crabs in the aquacultural industry of Scylla paramamosain. Since fasting occurs during molting, which requires a large supply of energy, internal energy reserves are critical. However, the dynamics of energy supply during pubertal molt is not clear. This study focuses on the variations of carbohydrates and lipids in serum during the pubertal molt of S. paramamosain via a metabolomics approach. Eleven lipid or carbohydrate metabolic pathways were significantly influenced postmolt. A remarkable decrease in carbohydrates in serum suggested that free sugars were consumed for energy. A significant decrease in glucose and alpha-d-glucosamine 1-phosphate showed that chitin synthesis exhausted glycogen, resulting in insufficient glucose supply. An increase in l-carnitine and acetylcarnitine, and a significant decrease in 15 fatty acyls and 8 glycerophosphocholines in serum indicated that carnitine shuttle was stimulated, and β-oxidation was upregulated postmolt. In addition, astaxanthin, ponasterone A, and riboflavin in serum were significantly decreased postmolt. Eleven potential metabolite biomarkers were identified for pubertal molt. Taken together, carbohydrates and lipids were possibly major energy reserves in pubertal molt. This study suggests that an increase in carbohydrate and lipid levels in crab feed may alleviate the effects of fasting during molt and improve farm productivity in mature female crabs.
The endosymbiont Wolbachia feminizes male isopods by making them refractory to the insulin-like masculinising hormone, which shunts the autocrine development of the androgenic glands. It was therefore proposed that Wolbachia silences the IR receptors, either by preventing their expression or by inactivating them. We describe here the two IR paralogs of Armadillidium vulgare. They displayed a conventional structure and belonged to a family widespread among isopods. Av-IR1 displayed an ubiquist expression, whereas the expression of Av-IR2 was restricted to the gonads. Both were constitutively expressed in males and females and throughout development. However upon silencing, altered gland physiology and gene expression therein suggested antagonistic roles for Av-IR1 (androinhibiting) and Av-IR2 (androstimulating). They may function in tandem with regulating neurohormones, as a conditional platform that conveys insulin signalling. Wolbachia infection did not alter their expression patterns: leaving the IRs unscathed, the bacteria would suppress the secretion of the neurohormones, thus inducing body-wide IR deactivation and feminization. Adult males injected with Wolbachia acquired an intersexed physiology. Their phenotypes and gene expressions mirrored the silencing of Av-IR1 only, suggesting that imperfect feminisation stems from a flawed invasion of the androstimulating centre, whereas in fully feminized males invasion would be complete in early juveniles.
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We analyzed the effects of 17β-estradiol (E2) injection and red light on the sexual maturation and vitellogenesis of the cleaner shrimp Lysmata amboinensis (De Man, 1888) by measuring the change of mRNA expression levels of eyestalk and vitellogenesis-related hormones induced by both factors. We examined the eyestalk crustacean hyperglycemic hormone (CHH) and vitellogenesis-inhibiting hormone (VIH) genes. The E2 injection did not affect changes of eyestalk hormones. The red light, however, caused a significant increase (P < 0.05) of CHH promoting maturity and a significant decrease of VIH, which suppressed vitellogenesis. The vitellogenin receptor (VTG-R) and mRNA expression (in situ hybridization) also caused the E2 injection and red-wavelength irradiation to induce synthesis of vitellogenin (VTG). Red-light-induced gonadal maturation, promoting hormone and VTG synthesis, but E2 did not change the eyestalk hormone. Red-light irradiation could thus be used as a novel, maturity-promoting alternative method in the culture of the species, which is different from the eyestalk-ablation method that has so far been used.
Estuarine crustaceans and fishes have highly evolved endocrine systems. Nevertheless, considerable endocrine involvement has been demonstrated in other estuarine invertebrates, particularly annelids and mollusks. Estuarine organisms face a wide variety of environmental problems, such as changes of salinity and temperature, that endanger them. Consequently, their endocrine systems have an important role in integrating the functions necessary to assure survival. Particularly important for survival of animals in an estuary, which is subject to wide salinity fluctuations, are the hormones that provide for salt and water balance, enabling the animals to regulate their “internal environment” within fairly narrow limits. Color changes also have adaptive significance, for example, by providing protective coloration. They are regulated by hormones in all crustaceans, and with few possible exceptions in all fishes. Furthermore, although hormonal regulation of growth and reproduction has been studied extensively in fishes and crustaceans, endocrine control of these two functions in other invertebrates also occurs. Other processes such as heart rate and carbohydrate metabolism are also hormonally controlled in at least some estuarine animals.
The suitability of bilateral eye stalk ablation as a means of induced breeding technique in S. hydrodroma was tested under laboratory conditions by considering growth and survival indices, reproductive indices, biochemical and histological indices. The daily growth rate (g) was higher for ablated males(0.3±0.2) against 0.16±0.09 in control males. A positive correlation with feed intake of 0.71±0.04 (g) in ablated males against 0.62±0.84 in control males and a negative correlation with Hepatosomatic Index (%) of 7.02±2.4 against 13.77±3.2 are recorded. Female crabs shows less survival rate (%)compared to males (64±12.7/88±10.33). Ovarian and testicular index in comparison to control were found to be higher (0.2±0.08/0.15±0.02 and 2.6±0.33/1.08±0.06 respectively). Nutrient mobilization was evident from decreased muscular protein and carbohydrates as of hepatopancreatic lipid after extirpation and increased gonadal proteins, carbohydrates and lipids. The double extirpation procedure increased the number of oocytes, follicle diameter and number in females and an increase spermatozoa and spermatocytes in males as reveled by histological indices
This chapter encapsulates information on food, feeding behaviour, moulting, growth and neuroendocrine regulation of moulting and reproduction in lobsters. A lot of research has been carried out worldwide on growth and the processes controlling it in lobsters, mostly on homarid and palinurid lobsters. This chapter, through a review of documented research, describes the moult cycle in lobsters, which is similar to that of other crustaceans, and the process of growth that occurs with moulting. It also discusses differences in growth rates with age, sex and varying external factors, including food. The feeding behaviour in lobsters is also discussed. The relationship between growth, moulting and reproduction and the internal factors that regulate these processes are also dealt with. A detailed account of neuroendocrine hormones and mechanisms that play an important role in the lobster physiology is presented. An insight into the aspects presented here will help in developing rearing protocols for commercially important cultivable lobsters.
Mussel farms are one of the most important modalities of aquaculture and constitute almost 80% of the total bivalve production in Brazil, representing about 5% of the national production. Brachyuran crabs are common inhabitants of these environments and represent an important link in coastal marine food chains. The aim of this investigation is to describe the population structure of Panopeus austrobesus Williams, 1983 in a Perna perna (Linnaeus, 1758) farm located at the southeastern Brazilian coast. The samplings were carried out in the northeastern coast of São Paulo State. From May 2002 to April 2003, one mussel net was recovered monthly, and all individuals of P. austrobesus were collected. Population size-frequency analysis indicated a unimodal and non-normal distribution. Males were significantly larger than females, and the overall sex ratio significantly skewed from 1:1, female-biased. Recruitment occurred during the entire period, and ovigerous females were found in 11 months. The onset of sexual maturity was estimated around 5 mm cephalothorax width. Mussel farms represent an anthropogenic intervention in the sea landscape, causing environmental changes. However, these structures must allow species introduction, increasing their ecological and geographical distribution, and provide available space and food to establish new populations. This is particularly important for species with small populations, such as P. austrobesus. The results of this study attest the environmental counterpart role of the mussel farms. Once they can support populations, they may also help to reintroduce them into the area and could therefore be used in a consortium generating economic profits and acting as bioremediation tool, assuring the maintenance of the genetic patrimony.
The relationship between the molting cycle and gonadal maturation was investigated in the Pleoticus muelleri population from coastal waters of Mar del Plata, Argentina. The analysis of the molting activity revealed activity patterns that vary conspicuously with both the changes in shrimp reproductive status and the season. Males and females exhibited a molt synchronism and the intermolt lengthened during the reproductive season. Intermolt and early premolt females presented ripe ovaries, but in late premolt females, ovaries were in resorbed condition. The reproductive activity begins in spring and extends until autumn, with the maximum of impregnated females in summer. Ovarian development from immature to ripe was rapid in spring and summer, probably due to the increase in temperature and photophase. The potentiality of impregnation is independent of the size of females at least 6 g in weight. The large quantity of reserves and food needed for oocyte development was evidenced by the increment of the gonadosomatic index during maturation. Females showed higher hepatopancreatic indexes than males, which could be related to the high energetic requirement.
1.Ovary development in worker honeybees is inhibited by 9-oxodecenoic acid or its vapour. A scent from the queen, in addition to her 9-oxodecenoic acid, also inhibits oogenesis in workers, but it is less effective than the acid. The scent and acid do not work together synergically. Neither 9-oxodecenoic acid nor queen scent, nor the two together, are as effective in inhibiting oogenesis in workers as access to a live queen. Older, mated queens are more effective than younger, virgin ones. Injection of 9-oxodecenoic acid partially inhibits ovary development in workers, but does not inhibit queen rearing by them. The mode of action of this acid is still uncertain.
Three types of neurosecretory cells, designated A, B, and C, occur in the central nervous system of Paratelphusa hydrodromous. They are distinguishable by their sizes, the nature of their nuclei, and the secretory products in the cytoplasm. Their distribution and neurosecretory activity are recorded in this paper. All the three types occur in the thoracic ganglion, while the brain and tritocerebral connective ganglia contain only the A and B types. Examined alive under the phase-contrast microscope, the conspicuous A-cells reveal the presence of numerous tiny granules and dark spheroids in the cytoplasm. These spheroids are stainable by neutral red. In Golgi preparations the spheroid walls become black. These are sudanophil and probably represent lipochondria. The spheroids contain phospholipid and vitamin C. The granules of the cytoplasm probably represent the mitochondria.
The brain and thoracic ganglia contain within them a rich network of delicate capillaries which surround individual neurosecretory cells as well as groups of cells. The secretory products are possibly discharged directly into the blood.
1. Blood glucose levels in the crab Cancer borealis ranged from 0.4 mg./100 ml. to 29.3 mg./100 ml. with a mean value of 8.6 mg./100 ml. In the same animals blood reducing substances were in the range 3.3-29.5 mg./100 ml. with a mean of 11.6 mg./100 ml. Blood glucose and reducing substances in the other two species of crabs tested, Cancer irroratus and Carcinas maenas, were in the same ranges.2. Changes in the blood glucose level account for most of the variations in reducing substances; the other components remain approximately constant, at about 3 mg./100 ml. The relationship between blood glucose and reducing substances is thus a simple straight line one.3. Variations of blood sugar levels during the molt cycle were found in Carcinas maenas and probably occur also in Cancer borealis. Qualitative changes in blood sugar composition also occur.4. Significant changes also occur in Cancer borealis females carrying eggs and at this time the relationship between blood glucose and reducing substances changes, ...
1. In this part of my contemplated series of papers are reported some results concerning the histological investigation of the incretory elements responsible for the production of the two chromatophorotropic hormones in Sesarma, whose activities and distribution were experimentally dealt with in the preceding study.2. On the basis of the present histological findings, and their comparison with the experimental data, it has been concluded that the sinus gland and the neurilemma are responsible for the secretion of S hormone, whereas N hormone has its origin in a type of neurosecretory cell (γ neurosecretory cell) occurring in abundance in both the brain and the medulla terminalis.3. The secretory activity in all of these hormone sources is alike in that it shows nuclear secretion, but there are differences in the secretory behavior.4. The close relationship between the sinus gland and the neurilemma was substantiated on the basis of their fundamentally similar histological structure and their secretory beh...
The male reproductive cycles of Cambarellus shufeldti and Cambarellus puer were compared. Although form I males in breeding condition and ovigerous females of each species can be found at almost any time throughout the year, two peaks of reproductive activity were shown; a major peak in January, February, and March and a lesser peak in July. C. shufeldti shows a strong tendency toward continuous, year-round breeding; while C. puer shows more clumping of reproductive activities into the two peak periods. Males of both species show two major cycles of sperm production as adults, the first occurring during the first breeding season following the one in which they were spawned. A second cycle of sperm production occurs when the males are approximately one year old. Growth increment studies showed an average growth increment of approximately 0.45 mm in cephalothorax length per molt for each species, with 12 to 13 molts required for reaching maturity in C. shufeldti and 13 to 14 for C. puer.
In Platynereis dumerilii a cerebral incretion controls sexual development, comprising simultaneous maturation of the germ cells and epitokous metamorphosis to the so-called heteronereis stage. Only results obtained from females are reported in this summary.In stages with oocytes ranging in size from 80 to 140 μ, removal of either the brain or of the prostomium may accelerate normal maturation slightly. In worms with smaller oocytes the same operations prevent or at least impair sexual development. However, animals decapitated in these stages readily mature upon implantation of isolated prostomia into their coelom; this applies even to small fragments comprising a few segments of such animals. The time needed for maturation depends mainly on the sexual state of the donor whereas that of the host appears to be of little importance. Thus, sexual development takes much longer with a prostomial implant from a juvenile than with one from a nearly mature adult animal. Larval heads may induce fragments of juvenile females to mature within an extremely short time; hence there is not a specific “epitoke hormone”. It is more likely that the brain produces the same type of incretion throughout the whole span of life; the qualitatively different effects of this incretion must be determined only by its relative concentration; this is high in the presence of juvenile prostomia, and low after implantation of prostomia from mature animals or from tiny larval heads.Thus sexual development is envisaged as being controlled under normal conditions by a gradually decreasing hormonal titer, different processes being assigned to each concentration. This assumption would also account for the fact that germ cell maturation and metamorphosis usually take place simultaneously, although in experiments they may occur independently of each other.Graded UV-irradiation of the brain of intact animals with germ cells results in precocious maturation. The average span of time between irradiation and maturation equals that between decrease of photoperiod and maturation in previous experiments. This supports the view that the lunar swarming periodicity observed under natural conditions is due to photoperiodic suppression of cerebral endocrine activity.Amputation of a number of posterior segments stimulates the production of the cerebral incretions that are necessary for regeneration of the lost segments. Since the same operation effects a retardation of sexual development, it may be inferred from these experiments as well as from those quoted above that rate and pattern of sexual development are determined exclusively by the intensity of cerebral incretory processes, a high titer of hormone inhibiting, and a low titer facilitating, sexual development.The effects of implanted prostomium fragments obtained by transverse section agree well with previous histological results, which indicate a neurosecretory origin of the prostomial incretion.
1. There are four cytologically distinct types of neurosecretory cells in the eyestalk and brain of Orconectes virilis. Two of these neurosecretory cell types are restricted in their distribution to the x-organ. The other two cell types occur in all neurosecretory cell groups in the eyestalk and brain except the x-organ.2. The distribution of neurosecretory cell types has been compared with that described by Enami (1951) for Sesarma.3. The Type 2 neurosecretory cells are the only neurosecretory cells that undergo histologically demonstrable changes in secretory activity in relation to the molting cycle. It is suggested, therefore, that the Type 2 neurosecretory cells are the source of the molt-inhibiting hormone.4. Arguments are presented in favor of the view that at some time before molt a decrease occurs in the rate of release of molt-inhibiting hormone from the axon endings of the Type 2 neurosecretory cells. This decrease seems to be correlated with a concurrent accumulation of stainable material obse...
The gonadal and hepatic indices were determined. Even though the crabPortunus pelagicus is a continuous breeder, there appears to be three maximal periods of development of the gonad and hepatopancreas. The gonad
index is high in the months of November-January and June and the hepatic index shows the greatest development in the months
of November-January and August. There appears to be a direct relationship between gonadal and hepatopancreatic development.
These results have been discussed in the light of previous work.
A female specimen of the crayfish Orconectes limosus (Rafinesque), in which the right second pleopod has the shape typical of that of the male, is here discussed. It proves to have no androgenous gland. The presence of one external male sexual character in a female not provided with an androgenous gland is not in agreement with the present theory of sexuality in the Crustacea. A study of the androgenous gland of Orconectes limosus reveals that this organ is supplied by a plexus of arterial capillaries. In small Decapoda, such as Hippolyte or Atyaephyra, the androgenous gland is very poorly provided with such capillaries. The blood supply, therefore, is correlated with the volume of this organ.
The androgenic gland discovered in 1954 in the amphipod Orchestia gammarellus has been described in all the superorders of the higher Crustacea, except the Syncarida which have not yet been investigated. The androgenic gland is localized in the last thoracic segment, against the subterminal, ejaculatory part of the vas deferens. In the Isopoda and the Tanaidacea the gland may occur, according to the species, in front of or along the testicular utricles, against the seminal vesicle or against the vas deferens. In addition, it is often closely joined with the genital apparatus. The androgenic gland seems of genital origin. It acquires progressively in the course of the first intermolts (after the acquisition of the specific form) the morphological, cytological and cytochemical characters of the adult gland. The histological structure of the androgenic gland is relatively varied: types in simple strands, compound strands, spherules or lobules. The cytological aspect assumes, by contrast, a great uniformity. The size of the nuclei may vary between 3 and 10 μ, but the cytoplasm is always strongly pyroninophilous in summer. Holocrine secretion seems to be the general mode of functioning of the androgenic gland. Although interesting results have been recorded, many particulars remain still to be supplied on the histogenesis, histochemistry, the embryonic and postembryonic development of the androgenic gland
Crustaceans have complex behavior patterns. Among these are patterns con cerned with reproduction and more specifically mating (reviewed by Schöne,1961). Mating behavior patterns vary among different species and in a number depend upon the physiological condition of the female for their initiation. For example, in some species, mating is correlated with the pre-adult molt of the female and the transferred sperm are stored in the seminal receptacles of the female. Among the portunids, the male protects the pre-molt female and mating occurs immediately after she molts. This behavior is initiated by a pheromone released into the water by the pre-molt female (Ryan, 1966). In some brachyurans (e.g., Callinectes, Carcinus), mating is apparently dependent on a condition of ripeness of the ovary (Chidester, 1911; Broekhuysen, 1937). Among Majidae. Schöne (1968) reported that Maja verrucosa males protect the females bemieath them prior to mating. In some brachyurans submissiveness of the female when seized is necessary for mating to occur (Chidester, 1911). Finally, the mating posture varies amomig species. The initiation and probably other aspects of the mating behavior in these crus taceans evidently require rather specific conimunications between potential mates. In land forms this is often visual and auditory (Salmon and Atsaides. 1968) while in aquatic forms it may also be chemotactic. Chemotatic communication would simply involve one or more pheromones as imithe one clear-cut example (lescribed by Ryan (1966). In view of the interest in mechanisms of communication in Crus tacea as well as other organisnis it seemed of interest to report observations on mating behavior of the spider crab, Libinia einarginata (L.), and to describe for the first time a heretofore unrecognized male-female association, here called “¿�obstetricalbehavior.â€