Study On Effects Of Tweens On Rumen Digestion And Metabolism, Intake And Digestion Of Sheep

Four Xinjiang merino sheep, fitted with ruminal and duodenal cannulae, were used in a 4×4 Latin square design trial to study effects on rumen fermentation, protozoa, feed intake, disappearance in fore stomachs and digestion by supplementing different tweens. The four experimental treatments were (1)the basal diet (the control) , supplemented with (2)10g·d-1 Tween 40, (3)10 g·d-1 Tween 60 and (4)10 g·d-1 Tween 80. The results indicated that ruminal pH was significantly decreased (P<0.05) by T80 supplementation, and ruminal ammonia-N concentration was not affected. Compared with the control group, the total volatile fatty acid (TVFA) by T60 and T80 were increased by 8.25% and 13.01% respectively (P<0.05). The concentration of acetic, propionic acid and butyric acid by T60 were significantly (P<0.05) increased by 7.94%, 9.08% and 8.56% separately. The concentration of acetic, propionic acid and butyric acid by T80 were extremely (P<0.01) increased by 12.19%, 14.23% and 15.58% separately.But the effect was not significant by T40. CMCase activity by T60 and T80 were significantly (P<0.05) increased by 12.85% and 18.7% respectively, and was not effectted (P>0.05) by T40. The results indicated that population of prtozoa, concentration of MCP in rumen and intake of sheep were not affected by tweens. Dry matter and fiber disappearance in fore stomachs were improved 3.88% and 3.17% respectively by T80, and there was not effected on these indexes by T40 and T60. Fiber and hemicellulose digestion were improved 4.46% and 4.69% respectively by T80.It is inferred that the effects were different from different tweens, the rumen digestion and metabolism of sheep and fiber digestion were improved by T60 and T80.