Effect of dietary concentrate to forage ratio on growth performance, rumen fermentation and bacterial diversity of Tibetan sheep under barn feeding on Qinghai-Tibetan plateau

Northwest Institue of Plateau Biology, Chinese Academy of Sciences, Xining, China
Key Laboratory of Adaptation and Evolution of Plateau Biota, Chinese Academy of Sciences, Xining, China
University of Chinese Academy of Science, Beijing, China
University of Chinense Academy of Sciences, Beijing, China
Technology Extension Service of Animal Husbandry of Qinghai, Xining, China
Northwest Institue of Plateau Biology Chinese Academy of Sciences, Xining, China
Northwest Institue of Plateau Biology, Chinese Academy of Science, Xining, China
DOI
10.7287/peerj.preprints.27807v2
Subject Areas
Biodiversity, Microbiology, Veterinary Medicine, Zoology, Nutrition
Keywords
16S rRNA, Tibetan sheep, Concentrate-to-forage ratio, Rumen bacterial diversity, Rumen fermentation parameter, Growth performance
Copyright
© 2019 Liu et al.
Licence
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
Cite this article
Liu H, xu T, Xu S, Ma L, Han X, Wang X, Zhang X, Hu L, Zhao N, Chen Y, Pi L, Zhao X. 2019. Effect of dietary concentrate to forage ratio on growth performance, rumen fermentation and bacterial diversity of Tibetan sheep under barn feeding on Qinghai-Tibetan plateau. PeerJ Preprints 7:e27807v2

Abstract

This study aimed to research the effects of different dietary concentrate to forage (C:F) ratio on growth performance, rumen fermentation and bacteria diversity of barn feeding Tibetan sheep. The experiment contains fiver treatments (HS1, HS2 HS3, HS4 and HS5; n=8, respectively) based on dietary C: F ratios 0:100, 15:85, 30:70, 45:55, and 60:40, respectively. The ruminal bacterial community structure was investigated through high-throughput sequencing of 16S rRNA genes in V4 hypervariable region. The results showed that increasing dietary concentrate feed level from 0% to 60% exerted a positive effect on DMI, BW gain, gain rate and feed conversation ratio (FCR) in Tibetan sheep. The increases dietary concentrate feed level elevatedNH3-N, propionate and valerate concentrations, whereas, reduced molar ratio of acetate to propionate (A/P ratio) (P<0.05). For rumen bacterial diversity, increases in dietary concentrate content contributed to lower alpha diversity indexes including Shannon wiener, Chao1 and observed species, meanwhile, significantly increased the abundances of the phylum Bacteroidetes and the genus Prevotella_1 (P<0.05). In conclusion, increases dietary concentrate content improved the growth performance and Tibetan sheep fed diets of 45% concentrate obtained a better performance; the inclusion of concentrate in feed changed rumen fermentation from acetate fermentation to propionate fermentation, and improved the energy utilization efficiency of Tibetan sheep; the increased in concentrate content significantly reduced rumen bacteria diversity and changed the abundance of some core bacteria.

Author Comment

This is a peer-review submission to PeerJ. We have changed some unidiomatic description in the abstract, introduction, results and discussion sections.

Supplemental Information

The raw data of the growth performance of Tibetan sheep

The treatment HS1= concentrate to forage ratio 0:100, HS2= concentrate to forage ratio 15:85, HS3= concentrate to forage ratio 30:70, HS4= concentrate to forage ratio 45:55, HS5=concentrate to forage ratio 60:40. DMI=dry matter intake; DM consume= DMI×t, t is experimental time(d), BW=body weight; ADG= average daily BW gain . FCR= feed conversion ratio.

DOI: 10.7287/peerj.preprints.27807v2/supp-1

The supplementary materials of the manuscript

Table S1 The nutrition of concentrate and forage feed in the experiment. Table S2 The statistics of raw rate across the 20 different samples. Table S3 The relative abundance of the total phyla detected by taxonomic analysis (%). Table S4 The relative abundance of total genus detected by taxonomic analysis (%). Table S5 The relative abundance of the 8 most dominant bacteria at the phylum level. Table S6 The effect of increases dietary concentrate on the rumen bacteria at the genus level.

DOI: 10.7287/peerj.preprints.27807v2/supp-2

Clean data of Tibetan sheep in group HS1

The 2 sequences in the file are represented 2 samples of Tibetan sheep in group HS1.

DOI: 10.7287/peerj.preprints.27807v2/supp-3

Clean data of Tibetansheep in group HS1

The 2 sequences in the file are represented another 2 samples of Tibetan sheep in group HS1.

DOI: 10.7287/peerj.preprints.27807v2/supp-4

Clean data of Tibetan sheep in group HS2

The 4 sequences in the file are represented 4 samples of Tibetan sheep in group HS2.

DOI: 10.7287/peerj.preprints.27807v2/supp-5

Clean data of Tibetan sheep in groups HS3

The 4 sequences in the file are represented 4 Tibetan sheep in group HS3.

DOI: 10.7287/peerj.preprints.27807v2/supp-6

Clean data of Tibetan sheep in groups HS4

The 4 sequences in the file are represented 4 rumen samples of Tibetan sheep in group HS4.

DOI: 10.7287/peerj.preprints.27807v2/supp-7

Clean data of Tibetan sheep in groups HS5

The 4 sequences in the file are represented 4 Tibetan sheep in group HS5.

DOI: 10.7287/peerj.preprints.27807v2/supp-8

The nutritional composition of the whole diets among different treatments (% DM basis)

a The tratments HS1, HS2, HS3, HS4 and HS5 refer to the C:F ratios of 0:100, 15:85, 30:70, 45:55 and 60:40, respectively. b DM= dry matter; CP= crude protein; EE= ether extract; ADF= acid detergent fibre; NDF= neutral detergent fibre. c Manufactured by Menyuan Yongxing Ecological Agricultural Development Co., Ltd. Contained corn (48%), wheat (30%), soybean meal (7%), colza cake (6%)cottonseed meal (5%), , salt (1%), pre-mix (1%),CaHPO4 (1%) and CaCO 3 (1%).

DOI: 10.7287/peerj.preprints.27807v2/supp-9

The effects of different dietary C: F ratios on the growth performance of Tibetan sheep

a The treatments HS1, HS2, HS3, HS4 and HS5 refer to concentrate-to-forage ratios of 0:100,15:85, 30:70, 45:55 and 60:40. DMI=dry matter intake; DM consume= DMI×t, t is experimental time(d), BW=body weight; ADG= average daily BW gain . FCR= feed conversion ratio. Values in the same row with different superscripts are significantly different (P<0.05).

DOI: 10.7287/peerj.preprints.27807v2/supp-10

The effects of different dietary C: F ratios on the rumen fermentation parameters of Tibetan sheep

a The Treatments HS1, HS2, HS3, HS4 and HS5 refer to concentrate to forage ratios of 0:100, 15:85, 30:70, 45:55 and 60:40, respectively. b Values in the same row with different superscripts are significantly different (P<0.05).

DOI: 10.7287/peerj.preprints.27807v2/supp-11