The experiment was conducted to study the effects of different sources of vegetable oil on ruminal fermentation and microbial enzyme activities in sheep fed diets with equal level of linoleic acid. Four healthy crossbred male sheep [(Northeast semi-fine wool×Dorset sheep, (40±1) kg] fitted with cannulas were used in a 4×4 Latin square design. The experiment was divided into 4 periods with 16 d per period. The sheep were assigned to a control group (no addition) and 3 exprimental groups [group PO (4.00% peanut oil), group CO (2.84% corn oil) and group SO (2.86% soybean oil)]. The linoleic acid level of the 3 expermental groups was equal. The dynamic variations of pH, protozoa count, NH3-N concentration and volatile fatty acid （VFA） concentration in 24 h as well as microbial enzyme activites in the rumen fluid were determined. The results showed as follows: there were no significant effects of different sources of vegetable oil on the mean of pH, NH3-N concentration and VFA concentration （P>0.05）; the total volatile fatty acid (TVFA) concentration and protozoa count of group PO were significantly lower than those of the control group 1 to 4 h after ingestation （P<0.05）; the activities of filter paper cellulase (FPase), carboxymethyl cellulose enzyme (CMCase), glucosidase and pectinase of group PO were significantly decreased 1 to 4 h after ingestation （P<0.05）; there was no significant effect of different sources of vegetable oil on xylanase activity （P>0.05）. There was no negative influence of different sources of vegetable oil on ruminal fermentation in sheep fed diet with equal level of linoleic acid; supplemention of 4.00% peanut oil decreaed the activities of ruminal fiber degradation related enzymes, in which the activities of CMCase, pectinase, FPase and glucosidase were significantly decreased 1 to 4 h after ingestation.［Chinese Journal of Animal Nutrition, 2011, 23（5）：748 -754］
CAO Xiuqing，LIU Licheng，REN Yanfeng，LIU Dasen
. Effects of Different Sources of Vegetable Oil on Ruminal Fermentation and Microbial Enzyme Activities in Sheep Fed Diets with Equal Level of Linoleic Acid[J]. Chinese Journal of Animal Nutrition, 2011
, 23(05)
: 748
-754
.
DOI: 10.3969/j.issn.1006-267x.2011.05.007
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