Clarias gariepinus is a major cultivable fish species in Nigeria. The method of it seedling propagation and quality of seed produced is therefore crucial. In the present study, the effect of dietary supplementation of aqueous extract of Piper guineense on the milt quality of male catfish, C. gariepinus broodstocks was investigated. 75 male C. gariepinus (mean weight ± 407.5 g) were fed with four diets supplemented with 0.6, 1.2, 1.8 and 2.4 g aqueous extract of P. guineense dry fruit extract / 100 g feed respectively (designated as D2, D3, D4 and D5) and the control diet (D1) 2 times a day at 3% of body weight for 56 days. Fish fed experimental diets showed significantly improved growth performance and reproductive indices over the fish in control treatment. Higher (P < 0.05) gonadosomatic index was recorded for the fish fed dietary P. guineense compared to fish fed on control diet. This result revealed that supplement diets with P. guineense fruit aqueous extract improved gonadosomatic index, milt volume, milt count, motility duration, percentage motility, testosterone level and testicular histology of male C. gariepinus broodstocks and has a potential pro-fertility property which can be exploited in fish seed production by hatchery operators.

Keywords: Piper guineense, milt quality, gonadosomatic index, Clarias gariepinus