A Comparative Study of Growth Performance, Blood Biochemistry, Rumen Fermentation, and Ruminal and Fecal Bacterial Structure between Yaks and Cattle Raised under High Concentrate Feeding Conditions

Abstract

This study compared the growth performance, serum biochemical indicators, rumen fermentation parameters, rumen bacterial structure, and fecal bacterial structure of cattle and yaks fed for two months and given a feed containing concentrate of a roughage ratio of 7:3 on a dry matter basis. Compared with cattle, yak showed better growth performance. The serum biochemical results showed that the albumin/globulin ratio in yak serum was significantly higher than that in cattle. Aspartate aminotransferase, indirect bilirubin, creatine kinase, lactate dehydrogenase, and total cholesterol were significantly lower in yaks than in cattle. The rumen pH, acetate to propionate ratio, and acetate were lower in yaks than in cattle, whereas the lactate in yaks was higher than in cattle. There were significant differences in the structure of ruminal as well as fecal bacteria between cattle and yaks. The prediction of rumen bacterial function showed that there was a metabolic difference between cattle and yaks. In general, the metabolic pathway of cattle was mainly riched in a de novo synthesis of nucleotides, whereas that of yaks was mainly riched in the metabolic utilization of nutrients. This study provides a basis for understanding a rumen ecology under the condition of a high concentrate diet.

Keywords: blood metabolism; cattle; fecal bacterial; rumen bacterial; yaks.

Figure 1

α diversity and richness in ruminal bacteria in yaks and cattle given high concentrate diets. Alpha diversity indices, including Enveness (A), Faith_pd (B), Observed feature (C) and Shannon (D). The black dots in Figure (A) represent outliers.

Figure 2

(A) PCoA plots and (B) Venn diagrams of the rumen bacterial community. (C) a cladogram shows rumen bacteria from the phylum level to genus level based on the linear discriminant analysis (LDA) effect size (LEfSe) analysis in yaks and cattle given high concentrate diets.

Figure 3

(A) The rumen bacterial composition at the phylum level (the relative abundance > 0.5%) and bacteria in cattle and yaks. (B) The rumen bacterial composition at the genus level (top 20) and bacteria in cattle and yaks given high concentrate diets. A single asterisk (*) indicates a significant difference at p < 0.05, while double asterisks (**) indicate a significant difference at p < 0.01.

Figure 4

α diversity and richness in fecal bacteria in yaks and cattle given high concentrate diets. Alpha diversity indices, including Enveness (A), Faith_pd (B), Observed feature (C) and Shannon (D). The black dots in Figure (A,C,D) represent outliers.

Figure 5

(A) PCoA plots and (B) Venn diagrams of the fecal bacterial community. (C) a cladogram shows fecal bacteria from the phylum level to genus level based on the linear discriminant analysis (LDA) effect size (LEfSe) analysis in yaks and cattle given high concentrate diets.

Figure 6

(A) Fecal bacterial composition at the phylum level (the relative abundance > 0.5%) and bacteria in cattle and yaks (B) Fecal bacterial composition at the genus level (top 20) and bacteria in cattle and yaks given high concentrate diets. A single asterisk (*) indicates a significant difference at p < 0.05, while double asterisks (**) indicate a significant difference at p < 0.01.

Figure 7

Stamp analysis in the KEGG metabolic pathway of rumen bacteria in yaks and cattle given high concentrate diets.

Figure 8

Correlation analysis between rumen differential bacteria and significantly different growth performance, serum biochemical indexes, and rumen fermentation parameters in cattle and yaks given high concentrate diets. A single asterisk (*) indicates a significant difference at p < 0.05, double asterisks (**) indicate a significant difference at p < 0.01, and triple asterisks (***) indicate a significant difference at p < 0.001.