Effect of energy sources and levels supplementation on ruminal fermentation and microbial protein synthesis in dairy steers

Abstract

Four rumen fistulated dairy steers were randomly assigned according to a 4 x 4 Latin square design with a 2 x 2 factorial arrangement of dietary treatments (Factor A = source of energy; CM = corn meal, CC = cassava chip), (Factor B = level of supplementation; 1 and 2% of BW). Four dietary treatments were used: CM1, CM2, CC1 and CC2, respectively. The results exhibited the differences between levels of CM and CC as energy sources. Supplementation of cassava chip at 2 %BW resulted in lower ruminal pH did of CM1, CM2, CC1 (P<0.05). However, ruminal VFA concentrations were similar. Moreover, cellulolytic bacteria populations decreased according to energy source and supplementation level. Furthermore, DM and CP digestibilities were significantly different (P<0.05) among treatments. The result from this experiment suggested that energy sources; cassava chip, affected bacteria and fungi ecology (P<0.05), especially at high level of supplementation at (2% BW).

Keywords

• cassava chip
• corn meal
• rumen fermentation