Effects of Feeding Rubbed Bamboo Silage on Growth and Carcass Traits of Fattening Japanese Black Steers

Abstract

The objective of this study was to evaluate the utility of rubbed bamboo silage (RBS) as the roughage in fattening beef cattle. Eight Japanese Black steers (10 months old) were divided into two groups: one group was fed rice straw (Control Group) and the other was fed RBS (Experimental Group). Rearing methods except for provision of the roughage were the same in both groups. Both groups were fattened until they were 28 months old, followed by slaughter. The feed consumption of Experimental group decreased gradually after they were 18 months old. The time spent eating behavior by cattle of Experimental group was significantly smaller than that of Control group, when they were 11, 22 and 25 months old, and their rumination behavior was also smaller when they were 11, 13, 18 and 22 months old (P<0.05). Furthermore, the roughage value index (RVI) and ruminal pH of Experimental group were significantly lower than those of Control group, when they were 18 months old (P<0.05). The body weight of Experimental group decreased after they were 24 months old. Although the finishing body weight of Experimental group was 100kg lighter than that of Control group, the carcass traits were not different between the groups. Gross pathological changes in rumen inside wall were not observed in either group. There were also no differences in the length and density of ruminal papillae between groups. In conclusion, rubbed bamboo silage can serve as an alternative roughage source for fattening beef cattle, but longtime feeding (over 10 months) may give negative impacts on their growth and beef production.