The aim of this study was to evaluate the effect of different release rate of rumen modulators on fermentation characteristics and S. bovis number in vitro by the means of induced by subacute rumen acidosis (SARA) model. Three Xuanhan steers fitted with permanent ruminal cannulas were used and SARA was induced by adding corn and fresh distilled grain(1∶1). Then this experiment was divided into 4 groups: 6 h release group, 8 h release group, 10 h release group and the control group. The samples were taken at 0,2,4,6,8,10 and 12 h after the SARA model was induced and the rumen fermentation parameters were determined and S. bovis number was quantitated using 16S rRNA oligocecleotoide probe hybridization. The results showed that pH in all trial groups were significantly increased compared with that in the control group （P<0.01）, and ruminal acetate, propionate, butyrate and TVFA concentrations were significantly decreased (P<0.05), while ruminal lactate content decreased significantly (P<0.05). The results indicate 8 h release group can effectively reduce pH, promote the growth of microorganisms and improve the rumen fermentation.［Chinese Journal of Animal Nutrition, 2011, 23（9）：1608 -1614］
DONG Lifeng，WANG Zhisheng，DU Yu
. Effect of Different Release Rate of Rumen Modulators on Fermentation Characteristics in vitro Induced by SARA[J]. Chinese Journal of Animal Nutrition, 2011
, 23(09)
: 1608
-1614
.
DOI: 10.3969/j.issn.1006-267x.2011.09.021
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