Welcome to Acta Prataculturae Sinica ! Today is Share:

Acta Prataculturae Sinica ›› 2023, Vol. 32 ›› Issue (12): 189-197.DOI: 10.11686/cyxb2023091

Previous Articles    

Effect of different concentrate to forage ratios on the structure of microflora in yak manure

Hong-xin NIE1,2,3(), Yu-min LI1,2,3, Kai-yue PANG1,2,3, Sha-tuo CHAI1,2,3,4, Di SHEN1,2,3, Zi-ming ZENG1,2,3, Yang LIAO1,2,3, Xun WANG1,2,3, Bin XUE1, Shu-jie LIU1,2,3, Shu-xiang WANG1,2,3,4(), Ying-kui YANG1,2,3,4()   

  1. 1.Qinghai Academy of Animal Husbandry and Veterinary Sciences,Qinghai University,Xining 810016,China
    2.Key Laboratory of Plateau Grazing Animal Nutrition and Feed Science of Qinghai Province,Xining 810016,China
    3.Yak Engineering Technology Research Centre of Qinghai Province,Xining 810016,China
    4.Key Laboratory of Animal Nutrition and Forage for Plateau Grazing Yak and Tibetan Sheep,Ministry of Agriculture and Rural Affairs,Xining 810016,China
  • Received:2023-04-02 Revised:2023-04-19 Online:2023-12-20 Published:2023-10-18
  • Contact: Shu-xiang WANG,Ying-kui YANG

Abstract:

The aim of this experiment was to study the effects of different ratios of concentrate to forage on the structure of the microflora in yak feces. Twenty-four healthy 3-year-old male yaks with similar body weight were randomly divided into two groups: One group was fed with a diet with a low concentrate to forage ratio (35∶65, C35 group), and the other group was fed with a diet with a high concentrate to forage ratio (65∶35, C65 group). The pretest lasted for 15 days and the experiment lasted for 90 days. Then, 16S rDNA high throughput sequencing technology was used to analyze the structural changes in fecal microflora. The main results were as follows: 1) A total of 1702 operational taxonomic units (OTUs) were detected in the feces of the two groups, among which 1273 OTUs (74.79%) were common to the two groups. The number of species, Chao1 index, and Shannon’s index were significantly higher in the C35 group than in the C65 group (P<0.05). 2) In terms of species composition of the microflora in yak feces, at the phylum level, Patescibacteria and Cyanobacteria were significantly more abundant in the C35 group than in the C65 group (P<0.01), and Actinobacteriota were significantly more abundant in the C35 group than in the C65 group (P<0.05). Bacteroidota and Spirochaetota were more abundant in the C65 group than in the C35 group (P<0.05). 3) Ruminococcus were significantly more abundant in the C35 group than in the C65 group (P<0.01), and Lachnospiraceae_NK3A20_group were significantly more abundant in the C35 group than in the C65 group (P<0.05). The number of uncultured was significantly higher in the C65 group than in the C35 group (P<0.01). The numbers of uncultured_bacterium, Alloprevotella, and Treponema were significantly higher in the C65 group than in the C35 group (P<0.05). 4)Prediction of the metabolic pathways and functions of fecal microorganisms at the KEGG2 level using PICRUSt revealed a much higher relative abundance of gene families involved in replication and repair, translation, nucleotide metabolism, biosynthesis of other secondary metabolites, and cell growth and death in the C65 group than in the C35 group (P<0.01). In conclusion, the dietary concentrate to forage ratio significantly affected the diversity and richness of yak fecal microflora. A diet with a high concentrate to forage ratio (65∶35) promoted the proliferation of non-fiber-degrading bacteria and increased the abundance of Alloprevotella, but inhibited the growth of Lachnospiraceae. These results enrich our understanding of the composition and functions of bacterial communities in yak feces.

Key words: concentrate to forage, yak, 16S rDNA, manure, microflora