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Fork length and sex ratio of Liza falcipinnis in Ebrié and Grand Lahou lagoons; n = number of specimens; * = p <0.05
Source publication
The reproduction of Liza falcipinnis were investigated in both lagoons (Ebrié and Grand-Lahou) from January 2006 to december 2007. 2162 specimens were examined (914 and 1248 respectively in Ebrié and Grand-Lahou lagoons). Fork length was taken to the nearest 1 mm, and total body weight (TW) and eviscerated body weight (EW) to the nearest 0.1 g. The...
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... < 0. 05). The spatio temporal distribution of sex ratios showed a predominance of females over the males however the lagoon (Table 1). Two periods of unequal distribution were observed in each lagoon. ...Context 2
... periods of unequal distribution were observed in each lagoon. The Ebrié lagoon where from January to March and May to July then from October to November where the sex ratio is in favour of the females with strong proportions (1: 1.18 to 1: 7.67) on the other hand, in April, August to September, the sex-ratio is reversed in favour of the males (Table 1). As for the lagoon of Grandlahou, the phenomenon is the same one with a predominance of the females from February to [DJADJI et. ...Context 3
... ©International Journal of Research -GRANTHAALAYAH [118] April, June to July and October at December against January, March, August and September which are in favour of the males (Table 1). The first sexual maturity size was 21.0 cm (FL) for males and 27.9 cm (FL) for females in Ebrié lagoon and, 24.7 cm (FL) for males and 27.9 cm (FL) for females in Grand Lahou lagoon ( Figure 2). ...Similar publications
The aim of this study was to analyse the morphological and physiological maturity of the crab Aratus pisonii at Mundaú Lagoon, Alagoas, Northeastern Brazil. A total of 594 specimens were collected, being 212 males and 382 females, of which 150 were ovigerous females. More females than males were found in most months except July/2015. The morphologi...
Size at first maturity of Terapon jarbua was studied based on 114 male (14 to 28 cm in TL) and 140 female (14 to 32 cm in TL). The Logistic curves describing the relationship between the sexes and the proportion of 50% maturity (Lm50) were estimated at 20.8 cm in male and 21.8 cm in female of Terapon jarbua. The male reached 50% first sexual maturi...
Citations
... Just as observed in the MPA of Niamone-Kalounayes, a breeding period ranging from the mid-dry to early wet season has also been reported in P. grandisquamis in Côte d'Ivoire (Alla and Adepo-Gourene 2020). Other studies have shown that gonadal maturation can begin in the dry season and end in the wet season in the majority of Mugilidae, corroborating results from this study (Albaret 1984;Albaret and Legendre 1985;Djadji et al. 2018). At this time of year, environmental and trophic conditions are therefore more favorable to ensure larval development and survival of fry (Pagès and Citeau 1990). ...
... Just as observed in the MPA of Niamone-Kalounayes, a breeding period ranging from the mid-dry to early wet season has also been reported in P. grandisquamis in Côte d'Ivoire (Alla and Adepo-Gourene 2020). Other studies have shown that gonadal maturation can begin in the dry season and end in the wet season in the majority of Mugilidae, corroborating results from this study (Albaret 1984;Albaret and Legendre 1985;Djadji et al. 2018). At this time of year, environmental and trophic conditions are therefore more favorable to ensure larval development and survival of fry (Pagès and Citeau 1990). ...
In Senegal, studies on the family Mugilidae are rare and little data is available on their reproductive biology. This study, carried out in the MPA of Niamone–Kalounayes (Casamance River estuary, Senegal) aims to enhance our knowledge of the reproductive biology of the largescale mullet, Parachelon grandisquamis (Valenciennes, 1836), a species highly prized by the local population as a food source. To better understand its reproductive biology, a series of monthly samplings over twelve (12) months from July 2021 to June 2022 was carried out. Experimental fisheries were carried out at six (6) stations located in secondary channels lined with mangroves, using a seine net (250 m long and 25 mm mesh side). A total of 361 individuals were sampled, including 321 female specimens and 40 male specimens. The calculated sex ratio was in favor of females (1:8), with a significant difference between the calculated sex ratio and the theoretical 1:1 sex ratio (χ ² = 218.73; P -value < 0.05). In the MPA of Niamone–Kalounayes, the breeding period of P. grandisquamis extends from March to July, from the end of the dry season up to the beginning of the wet season. The sizes at first sexual maturity were 17 cm in males and 18 cm in females, showing that in the MPA of Niamone–Kalounayes, males and females of P. grandisquamis reach sexual maturity at very close sizes (χ ² = 0.02; P > 0.05). As this species is subject to the intense fishery by many actors in the area, these findings may be proven useful in the process of developing a management plan for this particular species.
... Environmental factors probably accounted for most of the variations observed in Mullet fishes spawning times (Cardona, 2006;Luc-Gervais et al., 2018). ...
... In this work, the increase in the oocyte diameter of Liza carinata was evident from September (388 ± 15.8 µm) to January (569 ± 24.8 µm). The increase in egg diameter was mainly due the deposition of large amounts of proteins and lipids in the developing eggs (Luc-Gervais et al., 2018). ...
... It decreased thereafter from September (2019) to November (2019) showing a period of sexual rest. [10] reported that gonadal maturity began in September (dry season) and was completed in November (rain season) for the same species from two lagoons in Cote D-Ivoire and this coincide with flood season of the area and thus creates an ideal condition for the survival of larval and fingerlings due to abundance of food. During flood season nutrients are drained by the rich run-off in organic matter, the decomposition of organic matter enriches the environment in mineral salts which will lead to proliferation of algae according to [20] . ...
... 1:2.3, 1:2.4 male: female respectively). [10] also reported the dominance of female Liza falcipinnis from Ebrie and Grand-Lahou lagoon. He stated that the reason may be due to higher mortality of the male at larva stage and less accessibility of the male due to ethological differences related to sex. ...
A study on seasonal abundance, morphometric and meristic data, growth pattern, condition factor, sex ratio and gonadosomatic index of Liza falcipinnis (Valenciennes, 1836) from the Ojo axis of Badagry creek, Nigeria was conducted from May 2019 to March 2020. A total of 1012 species were randomly selected, having 499 females and 513 males. The length frequency analysis and length-weight relationships (LWR) were determined. Sex ratio was determined by Chi-square analysis. The results showed that morphometric data are: 0.5 - 2.5 mm for ED, 2.1 - 12 mm for HL, 1.7 - 8.1 mm for HD, 2.5 - 11.7 for BD, 2.6 - 233.3 mm for TL and 9.23 - 1006 g for BW for the combined sexes. The slope (b) shows an allometric growth pattern. The intercept ‘a’ and slope ‘b’ of the LWR (LogW = a + bLogL) were Log W=15.39+ 0.34 LogL (r= 0.54) for combined sexes, Log W= 12.49+ 0.02 log L (r= 0.38) for males and Log W= 18.23+ 0.01 log L (r=0.16) for females.The length frequency distribution indicated that species were dominated by two year classes (Ages 1 and 2). Condition factors were generally low. The values ranged between 0.68 - 0.85 for combined sexes. The gonadosomatic index for female was highest in August, 2019 (17.77%) with Mean±SD of 2.88±0.75; which indicated the peak of spawning period in the study area.Sex ratio difference was significant (P<0.05). Sexual differences were significant; the females are phenotypically larger than the male.
Biological rhythms in animals are coordinated by external environmental factors. In teleost, the reproductive cycle is synchronized with seasonal changes in the climate. This synchronization is to ensure the maximum survival of young ones. The reproductive cycle in fish is under the control of the brain–pituitary–gonad (BPG) axis. BPG axis is regulated by external environmental factors. Some environmental stimuli trigger the release of gonadotropin-releasing hormone (GnRH) from the hypothalamus of the brain, which regulates the recreation of gonadotropin (follicle-stimulating hormone, FSH, and luteinizing hormone, LH) from the pituitary gland. FSH regulates the gonad development and LH regulates the final maturation and spawning. Environmental factors such as temperature, photoperiod, rainfall, and other physico-chemical parameters of water (dissolved oxygen, water temperature, salinity, hardness, pH, etc.) influence fish reproduction and breeding. Due to global climate change and global warming all these environmental factors are fluctuating, which influences the maturation, migration, spawning, development, sex ratio, and survival of the new recruits. The current review is focused on the effect of important environmental changes (stress), lunar cycle, and photoperiod on the fish reproductive cycle.KeywordsBreedingGonad developmentReproductive cycleEnvironmental factorsClimate change
Goldspot mullet, Liza parsia is a commercially important fish of South East Asia, where its farming depends on wild seed resources due to unavailability of hatchery technology. It, therefore, is important to understand the annual reproductive cycle of female L. parsia in captivity. In this study, adult male and female L. parsia (body weight ranges: 45-90 g; total length ranges: 100-125 mm, age >1 year) were collected from the wild and reared in a brackishwater pond. Thereafter, fish were randomly sampled at monthly intervals to measure the hepatosomatic index (HSI), gonadosomatic index (GSI), levels of serum steroids (testosterone, T; 17β-estradiol, E2 and 17α-hydroxyprogesterone, 17-OHP), and oocyte growth. Results exhibited that female L. parsia undergoes six different maturation stages, namely I (oocyte diameter, OD: <100 µm), II (OD: 100-350 µm), III (OD: 350-400 µm), IV (vitellogenic oocyte, OD: 400-450 µm), V (ripe oocyte, OD: 450-550 µm) and VI (atretic oocyte, OD: 60-150 µm), with synchronous oocyte development. The highest (P<0.05) HSI (1.96±0.24) and GSI (12.01±0.73) were recorded in December and January, respectively. Concentration of E2 gradually increased from August and reached its peak (807.67±25.98 pg mL⁻¹, P<0.05) in December. The level of 17-OHP (85.87±0.91 pg mL⁻¹) was at its peak during the normal spawning month (January) (P<0.05). Overall, the results indicated that L. parsia attains maturity in brackishwater pond, which is consistent with previous observations, and altogether provide the basis to develop a breeding technology in captivity through hormonal and environmental manipulations.
