The growth performance, survival and reproductive success of Clarias gariepinus broodstocks were examined as they responded to 17-methyl testosterone (MT) and absolute ethanol mixed in their feed in varying levels of 50 mgKg-1 /MT, 100 mgKg-1 /MT and 0 mgKg-1 /MT. These inclusion levels also served as the three treatments TC 50, TC 100, TC 0. A total of 24 Clarias gariepinus broodstocks were stocked in six (6) concrete stagnant systems of 4 (2 males, 2 females) fishes per tank of 2metre by 2metre square, with duplicated treatments of TC 50 and TC 100. Treatment TC 0 was also duplicated, and served as the control, with 4 fishes per tanks (2 males and 2 females). Duration was for ninety (90) days. The mean initial weights were taken as 2.05 ±353.56g for treatment TC 50, 1.60 ±282.84g for treatment TC 100 and 1.65±494.98g for treatment TC 0. Highest mean weight gain of 3.45±2.22g observed in the study was seen in the Clarias gariepinus broodstock tank TC 50. Performance index showed treatment TC 50 performed highest with value 601.85±239.09. Survival rate was high in treatment TC 50 with 50.0±0.00%, higher in treatment TC 0 with 62.50±17.68% and highest in treatment TC 100 with 87.50±17.68%. Condition factor K was greater than 1 throughout the study showing well-being of the fishes; highest in treatment TC 50 at value 7.20. Water quality parameters were at normal ranges throughout the study.

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The growth performance and survival rate of monosex Heterobranchus longifilis juveniles were examined. A total of 144 Heterobranchus longifilis juveniles were stocked in eighteen (18) concrete tanks at stocking density of sixteen (16) fishes per tank of 2 by 2 metre square in flow-through and stagnant water systems triplicated for fifty six (56) days. Mixed sex tanks of Heterobranchus longifilis served as the control. The mean initial weight was taken as 1.22±0.00g while the highest mean final weights were 7.86±0.12 a g and 6.34±0.02 c g for monosex females and males in stagnant culture THFS and THMS. Heterobranchus longifilis also showed highest Specific growth rate of 3.80±0.03g in the female stagnant system THFS. Food conversion ratio and Feed conversion efficiency were highest in female flow-through tank THFF and stagnant tank THFS with values 4.09±0.00 a and 16.83±0.08 a. Performance Index showed Heterobranchus longifilis mixed sex performed better than the flow-through monosex culture of Heterobranchus longifilis. High survival rate 95.83±4.17% was seen in female stagnant tanks THFS. Lowest survival rates were recorded in the monosex flow-through and stagnant systems of Heterobranchus longifilis. Condition factor K was greater than 1 throughout the study for both species. Values were closely similar for the specie in monosex and mixed sex culture. Water quality parameters were at normal ranges for freshwater culture, throughout the study. It is recommended that concrete flow-through and stagnant systems be used for monosex and mixed sex culture of Heterobranchus longifilis.

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