The global exponential growth in the human population has resulted in a decline in food availability. Thus, the production of protein-rich aquatic food is high on the agenda. Feed accounts for 60% of total expenditure in aquaculture. This study was designed to examine the optimal inclusion level of barley meal (BM), competitive plant proteins, as a fishmeal replacer in the formulation of diets, to evaluate its effects on the carcass composition, immunity, and mineral absorption in common carp. Six experimental diets using BM as an alternative protein source containing different graded levels of BM (0%, 10%, 20%, 30%, 40%, and 50%) were prepared. Three replicates were used for each treatment having fifteen fingerlings per tank. Fingerlings were fed at the rate of 4% wet weight twice a day for 70 days. The results revealed that C. carpio fingerlings given 20% BM, as a protein source (BM-III) had the most improved carcass composition (crude protein; 17%, crude fat; 8%, gross energy; 3kcal/g, ash; 6% and crude fiber; 2%), immunological indices (WBCs; 7.48×103mm-3) and minerals absorption (Ca; 72.47%, Na; 67%, K; 71% and P; 73%). Results indicated that 20% replacement level of BM with the fish meal is best suited to improve carcass composition, immunity, and mineral absorption and for the production of eco-friendly feed. Moreover, 30% inclusion rate of BM was also found to be useful in the diets of carp species.
Novelty Statement | Barley meal was firstly used in fish feed specially for the common carp fingerlings. It was firstly tested for the mineral absorption and body composition. Use of the Barley was found very beneficial for these fish when was used at the level of 20-30% as replacement of fish meal.