DIETARY EFFECTS OF TIGER NUT Cyperus esculentus (LINNAEUS, 1753) ON MILT QUALITY OF AFRICAN CATFISH Clarias gariepinus (BURCHELL, 1822)

Abstract

The dietary effects of Cyperus esculentus seed powder were examined on the milt quality of African catfish (Clarias gariepinus) broodstock with the average body weight (487.09±13.57g). Five diets with crude protein of 40% were formulated with different inclusion levels of Cyperus esculentus seed powder. D1 (control) has 0 g/100g of the feed, while D2, D3, D4 and D5 has 0.5, 1.0, 1.5, 2.0g/100g feed respectively. The experiment was carried out for a period of 70 days. A total number of 45 Clarias gariepinus were randomly distributed in triplicate into 15 concrete tanks (2x2x1.5m). The fish were fed at 3% of body weight twice a day between the hour of 08.00-09.00hr and 16.00-17.00hr and constant water level of 1m was maintained. At the end of the feeding trial, weight gain, gonadosomatic index and reproductive indices (milt volume, motility duration, milt count, percentage motility, percentage fertilization, percentage hatchability and percentage survival of fry) were determined. The fish fed D5 had the highest mean weight gain (215.17±11.62g), motility duration (3.23±0.08sec), milt concentratrion (23.00x104±1.84), percentage motility (94.57±1.85%), percentage fertilization (94.00±1.29%), percentage hatchability (79.17±10.09), percentage survival (91.04±5.05%) and gonado-somatic index (0.76±0.45%), while the weight of the testes of the fish fed D4 weigh highest (4.04±1.24g) with motility volume of 1.20±1.14ml. The control diet D1 had the lowest values in most of the parameters. There was high spermatozoa concentration in the seminiferous lumen in the testicular histology of fish fed diets D3, D4 and D5, suggesting a better spermatogenetic activity of Cyperus esculentus. This study revealed that dietary inclusion of Cyperus esculentus improves fertility in Clarias gariepinus which will improve fish seed production.