G Maheswarudu

Cyclic feeding of low and high protein diets reduces production cost of Labeo rohita (Hamilton, 1822)

Eighty four days feeding trial (3 feeding cycle ; each cycle of 28 days comprising 21 days with low protein and 7 days with normal or high protein diets) was conducted with Labeo rohita fingerlings to investigate the growth performance. Four diets; D1 (10% CP); D2 (30% CP); D3 (35% CP) and D4 (40% CP) were prepared. A total of 225 fingerlings were distributed randomly into five treatments in triplicates. T1 and T2 groups were fed with D1 and D2 diets respectively throughout the experimental period. The feeding cycle of 28 days consisted of 21 days feeding with D1 and 7 days with D2 (T3); D3 (T4) or D4 (T5). Higher growth rate in terms of specific growth rate, feed conversion ratio and apparent net protein utilisation were found in T2 and T3 group compared to T4 and T5. However, protein efficiency ratio of T3 group was significantly higher than the T2 group (p<0.05). Highest and lowest content of protein and lipid was observed in T2 group, whereas, the ash content was highest in T1 group. Feeding cost was considerably reduced with T3 group of low protein intake (43.63%) registering 20.17% saving in production cost. The results indicate that fish fed with cyclic feeding schedule of 21 days with D1 (10% CP) followed by 7 days with a normal diet, D2 (30% CP) could reduce the production cost with considerable savings in feed cost.