Dietary protein level, microbial phytase, citric acid and their interactions on bone mineralization of Labeo rohita (Hamilton) juveniles

A feeding trial was conducted for 60 days to study the effect of dietary protein, microbial phytase and citric acid on intestinal digesta pH, bone ash and bone mineral contents in Labeo rohita juveniles. Eight experimental diets were prepared in 2 x 2 x 2 factorial arrangement with crude protein levels (25% and 35%), microbial phytase (0 and 500 U kg(-1)), and citric acid (0 and 3%). The 25% crude protein level feed was supplemented with phytase (U kg(-1)) and citric acid (%) at the level of 0,0 (C25); 500,0 (T1); 0,3 (T2); 500,3 (T3), and 35% crude protein level feed at 0.0 (C35); 500,0 (T4); 0,3 (T5) and 500,3(T6) respectively. One hundred and twenty juveniles of L. rohita (av. wt. 12.61-13.72 g) were distributed randomly in eight treatments, each of with three replicates. Addition of citric acid in the 25% crude protein feed significantly decreased (P