Supplementation Levels of Concentrate Containing High Levels of Cassava Chip on Rumen Ecology and Microbial Protein Synthesis in Cattle

Abstract

The object of this study was to determine the influence of supplementation of level concentrate containing high levels of cassava chip on rumen ecology, microbial protein synthesis in cattle. Four, rumen fistulated cattle with initial body weight of 400 ± 10kg were randomly assigned according to a 4 x 4 Latin square design. The dietary treatments were concentrate cassava chip based offering at 0, 1, 2 and 3 % BW with urea-treated rice straw fed ad libitum . It was found that ruminal pH was significantly decreased with increase of concentrate. Volatile fatty acids (VFA) concentration in the rumen was significantly different among treatments. In addition, a molar proportion of propionate was higher in supplemented groups at 2 and 3 % BW (P< 0.05), leading to significantly decreased acetate:propionate ratio. Furthermore, microbial N supply was significantly improved and was highest at 2 %BW supplementation. The efficiency of rumen microbial-N synthesis based on organic matter (OM) truly digested in the rumen was highest in level of concentrate supplementation at 2 %BW (80 % of cassava chip in diets). Moreover, the total protozoal counts were significantly increased, while fungal zoospores were dramatically decreased in cattle receiving increased levels of concentrate. In conclusion, cassava chip can be use as energy source at 80% in concentrate and supplementation of concentrate at 2 %BW with urea-treated rice straw as roughage could improve rumen fermentation efficiency in cattle.