Effect of methyl testosterone hormone on water quality in aquaculture fish farms in Uganda

Abstract

Tilapias are sexually reversed by hormonal treatment with 17α-methyltestosterone (MT) before introduction in culture unit to avoid over-breeding. This manipulation can be perceived as a real chemical hazard to environment. Therefore, this study was undertaken to evaluate the effect of using MT on water quality parameters in ponds. Two ponds having four hapas in each were used for the experiment and 15000 fry were stocked in each hapa. The experiment consisted of two treatments having three replications, in treatment one, fry meal without hormone was fed to the fry and in treatment two fry meal mixed with MT hormone was used. The fry were fed for four rounds done at 8:00am, 10:00am, 2:00pm and 4:00pm in each hapa in both ponds. Water quality parameters such as dissolved oxygen, pH, and turbidity were measured in intervals of three days at 7:00-8:00am, 12:00-1:00pm and 4:00-5:00pm. The parameters were measured using an oxygen probe, pH meter and secchi disc. It was found that most of the water quality parameters were within the suitable range among the two treatments. There was no significant difference in dissolved oxygen and pH at all time however a significant difference was noticed with turbidity at 4:00-5:00pm (p-value = 0.0047). The study revealed that the application of MT did not generally influence water quality parameters in tilapia ponds.