Usage of NaCl as a prophylactic medium for egg incubation and for rearing of the African catfish (Clarias gariepinus) at the stage of hatch and fry. Preliminary results

Results of NaCl treatment of African catfish culture are presented. The study was composed of four experiments carried out in different developmental stages of the investigated species, from egg to fry. No positive effect of sodium chloride on egg incubation nor hatch rearing was stated. The highest survival of embryos and hatch was recorded in the control group. Good results were obtained in the rearing of fry. In the first experiment with 5‰ concentration of salt the survival and growth were better than in the control group. Also in the second experiment in alternatives with increased concentrations, the results were better then in the control group, nevertheless the differences were statistically non-significant.