Abstract

The use of antimicrobial agents and antibiotics as remedial measures against fish diseases has been questioned. The huge amounts of antibiotics used in animal husbandry has exerted a very strong selection pressure on the resistance among bacteria, which have adapted to this situation, mainly by a horizontal and philandering flow of resistance genes. Prebiotics, probiotics and symbiotics have been proposed as strategic means to enhance feed utilization, growth and immunity in fish production. In the present trial, a total of 180 fish was divided into 4 groups of 3 replicates each. Each replicate contained 15 fish. The formulated diets were supplemented with prebiotic (Sargassum muticum), probiotic (Parkia biglobosa) and symbiotics (a combination of Parkia biglobosa and Sargassum muticum). Efficiency of the inclusion of prebiotics, probiotics and symbiotics in formulated diets was evaluated in African catfish, Clarias gariepinus fingerlings (mean weight 2.53±0.05g). Formulated diet was fed 5% body weight to a group of 15 fish (in 3 replica) for 12 weeks, compared to fish fed control pellet containing similar ingredients but was not supplemented. Results showed on the skin of fish fed probiotics diet recorded improved GST and SOD activity and less CAT activity whereas in the liver fish fed prebiotic and symbiotic diet showed improved GST and CAT activity relative to the control. There were significant (p<0.05) differences between fish fed the control diet and all treatments (prebiotic, probiotic, symbiotics). It may be concluded based on the results recorded in this study that prebiotics, probiotics and symbiotics supplementation in diets has positive effect on antioxidant enzyme activity in African catfish, Clarias gariepinus to improve resistance against bacterial infections.

Key words: African catfish, antioxidant enzyme, feed utilization, growth, diets.