Standardization of breeding and rearing of the endangered Indian catfish Clarias magur (Hamilton, 1822) for juvenile production

Abstract

The walking catfish, Clarias magur, is one of India's most popular food fish because of its nutritional quality and taste. In recent times, more attention has been given to this species due to the alarmingly decreasing availability in natural water bodies. Breeding and seed rearing of this species are still bottlenecks to an uninterrupted seed supply. A study was initiated to standardize the breeding performance of this species using the WOVA-FH hormone. Four hormone doses were selected (0.5, 1.0, 1.5 and 2.0 ml/kg body weight of female), and results indicated that the total weight of stripped eggs and spawning fecundity were the highest (p < 0.05) when females were injected with 1.0 ml of WOVA-FH hormone per kg of body weight. In the rearing experiment, the weight gain of larvae obtained from fishes injected with different hormone doses did not differ significantly (p > 0.05). Average larval growth at the end of 30, 60, 90 and 120 days of rearing was 0.003 g, 0.085 g, 4.47 g, 11.77 g and 23.77 g, respectively. For juvenile production from the fingerlings of C. magur, different protein levels (20 %, 25 %, 30 %, 35 % and 40 %) of feed were prepared from locally available feed ingredients, and the growth and survival performance of C. magur under varying protein levels were recorded. Results indicated that C. magur required relatively higher protein feed (35 %) for better growth performance, and varying protein level has a direct impact on the growth, survival, mineral and proximate composition of C. magur.