Mixed feeding schedule of low and high protein in the diet of Labeo rohita (Hamilton) fingerlings: effect on growth performance, haemato‐immunological and stress responses

Four experimental diets D 1 , D 2 , D 3 and D 4 having 100, 300, 350 and 400 g protein kg −1 diet, respectively, were prepared. Fingerlings of Labeo rohita (5.45 ± 0.03 g) were fed with different diets following a mixed feeding schedule with the feeding cycle of 28 days that consisted of either 28 days feeding of diet D 1 or D 2 or 21 days feeding with D 1 diet and 7 days with either D 3 or D 4 diet. Different treatments were T 1 (D 1 for 28 days), T 2 (D 2 for 28 days), T 3 (D 1 for 21 days and D 2 for 7 days), T 4 (D 1 for 21 days and D 3 for 7 days) or T 5 (D 1 for 21 days and D 4 for 7 days). Fingerlings were sampled after three feeding cycles (84 days). Higher ( P  < 0.05) growth performance and protein utilization efficiency were found in the T 3 group, which was similar to the T 2 group. The blood count, NBT , lysozyme activity, serum parameters and stress indicator parameters also complement for the better immunity in the T 2 and T 3 groups. Therefore, it could be concluded that fingerlings feeding alternately a low‐protein diet (D 1 ) for 21 days followed by a normal‐protein diet (D 2 ) for 7 days in a cycle of 28 days for 84 days maintained better growth and health status.