Utilization of valorized cassava leaf meal as an alternative feedstuff to defatted soybean meal in feed for rohu, Labeo rohita fingerlings

Abstract

Growth and physiological responses of rohu to substitution of defatted soybean meal (DSBM) by cassava leaf protein concentrate (CLPC) was studied. Three clusters of rohu fingerlings (average weight, 1.90 ± 0.05 g) were fed similar diets (300.00 ± 2.70 g/kg crude protein and 17.54 ± 0.06 kJ/g gross energy) in which 300 g/kg DSBM was replaced by 0, 33, 66 and 100 % CLPC for 60 days. Growth was not influenced by treatment; however, feed conversion increased linearly (P = 0.038). Insulin-like growth factor (IGF)-I gene expression was not altered by treatment whereas its binding protein (IGFBP-I) tended towards linear up-regulation (P = 0.052). Liver catalase and superoxide dismutase activities increased remarkably (P < 0.05) consequent of dietary CLPC. Hepatic and muscle malate dehydrogenase, lactate dehydrogenase, aspartate and alanine aminotransferases of the fish showed no distinctive variation (P > 0.05). Based on observed results, we concluded that 66 % dietary DSBM can be substituted by CLPC without impairing growth, feed utilization and intermediary metabolism of rohu.