Effect of Chemical Disinfectant (formalin) on Hatching of Eggs of African Catfish (Clarias gariepinus), Survival and Growth Performance of Fry

Abstract

Eggs of matured Clarias gariepinus size ranging from 550-800 g total body weight (TBW) were treated with 0.5 ml and 1 ml formalin concentrations for 60 seconds to determine its efficacy and effect on hatching, survival and growth performance of fry. Each treatment was replicated three times. The research was conducted at the Toxicology Unit at Fish Farm, Federal University of Technology, (FUT), Bosso Campus, Minna. Mean fecundity did not differed significantly (P>0.05); 138934", 110429 and 123470" for 0.5 ml, 1 ml and control among the treatments. Percentage fertilization and hatching differed significantly (P<0.05) between 1 ml, and 0.5 ml (64.43 and 54.59") and (62.48 and 42.59b) respectively. The bred hatchlings were maintained for 8 weeks and total percentage mortality was 15, 13 and 20 for 0.5 ml, 1 ml and control respectively. Mean Total Body Weight (TBW) gain differed significantly (P<0.05) between 1 ml (3.27ª) and 0.5 ml (0.82). Treatment three (1 ml formalin solution) gave better result in terms of fertilization, hatching and growth performance. This shows that eggs treated with formalin at 1 ml concentration for 60 seconds is appropriate to disinfect eggs. The treatment is hence recommended for disinfecting Clarias gariepinus eggs before incubation.