Effect of palm meal ration on compound stomach and rumen and their digestive enzyme activities in Tibetan ewes

The objective of this research was to investigate the effects of different proportions of dietary palm meals on the morphological development of the compound stomach, the antioxidant capacity of rumen contents, and the digestive enzyme activity of plateau Tibetan ewes. One hundred and twenty healthy 2 to 3-month-old weaned Tibetan Plateau ewes with similar body weights 18.39 ± 1.25) kg were randomly divided into four groups, with six replicates in each group and five ewes in each replicate: 0 (Control group), 15% (Test group I), 18% (Test group Ⅱ), and 21% (Test group Ⅲ) were fed with palm meal instead of corn as concentrate supplement. The experiment was divided into a pre-feeding period of 7 days and a pilot period of 90 days. The results show that: 1) The thickness of the rumen cuticle, the length of the reticulum papilla, the thickness of the muscle layer, and the thickness of the central muscle layer in the Control group were significantly less than those in Test group I (P < 0.05). 2) Compared with the Control group, the total antioxidant capacities of the rumen in Test group I and Test group Ⅱ were significantly increased (P < 0.05). The activity of superoxide dismutase in Test group I was significantly higher than that in the other three groups (P < 0.05). The catalase activities of the control group and Test group I were significantly higher than those of the other two groups (P < 0.05). 3) The activities of α-amylase and cellulase in the Control group were significantly lower than those in Test group I (P < 0.05). The activities of chymotrypsin and trypsin in the Control group were significantly lower than those in other groups (P < 0.05). In conclusion, replacing corn in concentrate with 15% palm meal can significantly promote the development of the compound stomach morphology of plateau Tibetan sheep and effectively improve the rumen antioxidant capacity and digestive enzyme activity.