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Influence of Broodstock Age on Reproductive Success in the African Catfish Chrysichthys nigrodigitatus (Claroteidae Lacépede, 1803)Abstract: The influence of female age and size on reproductive success and egg quality was investigated in Chrysichthys nigrodigitatus. Three confined groups were formed following fish age and size during spawning period. The results show that spawning rate increased with female age and size. Spawning rate was similar in 3+ and 4+ females (80 %). But only 50% of 2+ females have spawned. Absolute fecundity of C. nigrodigitatus was higher in 4+ females (9877 386) than in 2+ ones (6939 1024). The 3+ females had an intermediate absolute fecundity (8378 797). Nevertheless, relative fecundity decrease when the age of females increase. Moreover, egg size is positively strength correlated with female age. The 4+ females with a larger body size have produced large size eggs and larvae. Similarly, the hatching rate was higher in 4+ females intermediate in 3+ females and lower in the 2+ ones.
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