Use of Probiotics as First Feed of Larval African Catfish Clarias gariepinus (Burchell 1822)

Abstract

African catfish larvae do not have fully developed digestive system at onset of first exogenous feeding. Live feed like artemia have been used more than dry diets but is also costly. The gut microbiota may be influential in larval diet utilization. We therefore made three larval feed from two commercial probiotics and tested their growth and nutritional effects on first feeding hatchlings (larvae) of African catfish. The three diets were labeled as feed 1 (F1) made up of mixtures of mixtures of Lactobacillus acidophilus, Bacillus subtilis and Lactobacillus bugaricus, feed 2 (F2) was made up of 100% Saccharomyces cerevisiae and feed 3 (F3) was made up of 50% Lactobacillus mixtures and 50% Saccharomyces cerevisiae. The control diet F4 was decapsulated artemia. African catfish hatchlings were produced by artificial dry fertilization of brooders maintained in our lab. First feeding hatchlings 48 hours post fertilization (48 h pf) were stocked in well aerated 15l plastic aquariums at density of 100 larvae aquarium-1. There were three replicate aquariums per treatment feed. The photoperiod of the larval rearing system was 12 h D: 12 h L and the light intensity were maintained at 8 lux using black nylon coverings. The hatchlings were fed to satiation 5 times daily for the whole larval period of 20 days. Survival of larvae were similar (P>0.05), for those fed with feed 1 (100% mixed lactobacillus sp), (LAB) 62.59%, feed 2 (100% Saccharomyces cerevisiae) (SAC) 57.89% and feed 4 (decapsulated artemia) 57.89%. The lowest surviving larvae were those fed with F3, 50% LAB: 50% SAC 54.67%.Weight gain was however better for larvae fed with artemia AWG 0.15 g than the rest of the treatments (P<0.05). The larvae fed with 50% LAB: 50% SAC (F3) had higher AWG 0.11 g than those fed with LAB (F1) 0.07 g and SAC (F2) 0.09 g (P<0.05). The result indicates that probiotics can be used in enhancing growth and survival of larval of African catfish. Nutritional value of probiotics is similar to live feed. Prolonged use of artemia reduces survival.