Does feeding African catfish, clarias gariepinus vinegar-immersed poultry viscera affect its growth performance, hygienic status and pathogenic bacterial load?

Abstract

This study was conducted to investigate the effects of replacing commercial feed with vinegar-immersed poultry viscera on growth performance, physiological status and bacterial load of the catfish, Clarias gariepinus. Fish were fed on a commercial diet (T1), poultry viscera (T2) and poultry viscera immersed in commercial vinegar (T3). Catfish with an average body weight of 520g were stocked in circular fiberglass tanks each of 2 m3 water volume for 98 days. Water quality parameters, growth performance, feed utilization, flesh composition, serum analysis and bacterial load of feed, water and fish, were measured. Ammonia content in rearing water decreased significantly in T3 compared to T2. There were not any significant differences detected (P>0.05) in survival and growth performance, while significant (P≤0.05) differences in feed utilization and whole-body composition were detected among treatments. The quality indices of fish in terms of flesh composition were in favor of T3. A decrease in the serum’s total protein and albumin and an increase in the serum’s globulin and cholesterol levels were observed when fish was fed on poultry viscera only. Pathogenic bacterial load in feed, rearing water and fish intestine were at their lowest limit in T3. This study shows that C. gariepinus can feed on poultry viscera immersed in commercial vinegar as an alternative feedstuff source to commercial high-priced feed. The ecological impacts of treating environmentally hazardous by-products, like poultry viscera and converting it to a high value by-product are a matter of interest for both aquaculurists and environmentalists alike. More research work is needed to take advantage of the current results in a commercially applicable scale.