Evaluation of the Nile tilapia (Oreochromis Niloticus) body condition and fecundity under experimental conditions

Abstract

Reproduction in fish is one of the basic biological features enabling the maximum survival and continuation of the species. The present study was conducted to investigate the effect of body condition and environmental parameters on reproductive potential of Nile tilapia (Oreochromis niloticus) species under experimental condition. The study was conducted at Bugiyanya Zonal Agriculture Development Institute satellite station in Mbale. Young female broodstock from nursery were stocked into hapas set in earthen ponds at density of 2fish/m3 Male broodstock were introduced into the hapa when the females reached sexual maturity to facilitate spawning and mating. Eggs were collected from the buccal cavity of the female and counted; the total length, standard length and body weight of the fish were measured. Mean dissolved oxygen concentration was 5ml/l, mean temperature was 24θC and mean pH was 7.4. Fecundity was correlated with body weight (R2 =0.78), body condition (r=0.51) and total length (R2=0.091), fecundity was better correlated with body weight than length. Dissolved oxygen concentration significantly affected fecundity (One-way ANOVA, P<0.05). Temperature and pH values did not significantly affected fecundity (One-way ANOVA, P>0.05). The study recommends the use of younger female broodstock of 8 to 10 months old in breeding centers.