Effects of using fish bio silage as fish meal replacer on feeding, growth and gut histology in common carp Cyprinus carpio L. fingerlings

This study was carried out to evaluate the effects of locally produced fish biosilage as fish meal alternative on feeding, growth efficiency and gut histology in common carp C. Carpio fingerlings. Biosilage was prepared by fermenting marine bycatch fish with date fruit residues, domestic vinegar and citric acid. The produced biosilage was incorporated in feeds to replace 0, 25, 50 or 75% of fish meal protein. Fish were fed for 14 weeks and feeding and growth parameters were close in the four feed groups so as fish survival rate during the experiment (88.9-93.3%). Histological examination of intestine and liver sections has showed improvements when fish fed on the four different feeds. Initial fish group showed signs of nutritional deficiency through limited size of intestinal villi and hepatocytes. However, the histological structure of gut was improved after fish were fed on the experimental feeds without significant differences between fish meal or fish biosilage feeds. The study concluded that fish silage could replace fish meal without adverse effects on feeding, growth efficiency and gut histology