Influence of Roughage Sources and Protected Protein in Complete Feed Block on Nutrients Utilization, Growth Performance, Microbial Protein Synthesis and Body Composition in Crossbred Calves

摘要

Crossbred (KS) male calves (18, BW 201.20 kg) were randomly divided into 3 groups of 6 each. Calves in group T_1 were fed wheat straw (WS) based complete feed block (R:C, 60:40) while those in group T_2 were fed feed block in which 40% of WS of T_1 was replaced with dried sugarcane bagasse (SB) and those in group T_3 were fed complete feed similar to group except that its rapeseed cake was replaced with that treated with formaldehyde (1.2g/100g CP) as a source of protected protein. The complete feedblocks (CP 12%, TDN 55%), manufactured at 3000 psi at dwell time of 30 sec, were fed ad lib for 4 months along with 2 kg freshly chopped maize fodder daily. Total DM intake, average daily gain in body weight and feed conversion efficiency were higher ingroup T_3 than in groups T_1 and T_2, but differences among groups were not significant. DM digestibility was not influenced by 40% replacement of WS with SB, however, it was reduced (P<0.05) on incorporation of protected rapeseed cake in feed block. Feeding of feed blocks T_1 resulted in higher (P<0.05) OM digestibility than those of T_1 and T_3, however, NDF, ADF and cellulose digestibility was lower (P<0.05) in groups and T_3 than in group T_1. CP digestibility in groups T_2 and T_3 was numerically higher than in group T_1. Ca arid P balances were improved by the incorporation of SB as well as protected rapeseed cake in complete feed blocks, however, Ca and P retention as percent of intake remained similar amongst the groups. Nitrogen utilization, microbial-N supply and body composition of calves remained uninfluenced by dietary treatments. It was concluded that replacement of 40% WS in complete feed block with SB was economically advantageous, but replacement of rapeseed cake witrh protected rapeseed cake did not yield any improvement on the performance of crossbred calves. kw:Sugarcane