Molecular mechanism underlying the effect of illumination time on the growth performance of broilers via changes in the intestinal bacterial community

Yongfen Wang; Zhen Zhang; Pengkun Yang; Miaorui Zhang; Lei Xi; Qiong Liu; Jingang Li

doi:10.7717/peerj.9638

Molecular mechanism underlying the effect of illumination time on the growth performance of broilers via changes in the intestinal bacterial community

PeerJ. 2020 Aug 3:8:e9638. doi: 10.7717/peerj.9638. eCollection 2020.

Authors

Yongfen Wang^{1

2}, Zhen Zhang², Pengkun Yang², Miaorui Zhang², Lei Xi², Qiong Liu³, Jingang Li¹

Affiliations

¹ College of Life Sciences, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China, Shaanxi Normal University, Xi'an, China.
² College of Food and Biology Engineering, Henan University of Animal Husbandry and Economy, Zhengzhou, Henan, China.
³ College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China.

Abstract

The circadian rhythms associated with light have important effects on the growth, metabolism, immunity and reproduction of broilers. However, there is a lack of systematic evaluations of the effect of the light cycle on intestinal microbes and the nutritional metabolism of these microbes in broilers. This study was designed to study the effects of the light cycle on the intestinal bacterial community structure and growth of broilers. In this study, Arbor Acre (AA) broilers were fed under a short photoperiod (1L:23D), a long photoperiod (23L:1D), and a normal photoperiod (16L:8D), respectively. The feed conversion ratio of the broilers was calculated, and the levels of endocrine hormones, such as melatonin, insulin and glucagon, were determined. Intestinal contents were collected from the small intestines of the broilers after slaughtering, and the V3+V4 region of the 16s rDNA gene was sequenced. The results demonstrated that changes in the light cycle could affect the synthetic rhythms of melatonin, insulin and glucagon. Compared to short and normal photoperiod, long photoperiod significantly increased the abundances of Barnesiella species in intestinal microbes and decreased the abundances of Bacteroides and Alistipes species. Cluster of Orthologous Groups of proteins analysis indicated that prolongation of the illumination increased the abundances of bacterial genes with glycometabolic and membrane transport functions in intestinal microorganisms. A model was established in this study, and our results showed that prolonged illumination altered the intestinal microbial community structures of broilers, increased the absorption and utilization of polysaccharides in broilers, and reduced the feed-to-meat ratios. To the best of our knowledge, this is also the first study to describe the molecular mechanism underlying the effects of the light cycle on the uptake and utilization of nutrients that occur via modification of the intestinal microbial community structure in broilers.

Keywords: Feed-to-meat ratio; Illumination; Insulin; Melatonin; Microbial community.

Associated data

figshare/10.6084/m9.figshare.11860650.v1

Grants and funding

This work was supported by the National Natural Science Foundation of China (No. 31802111), the Scientific and Technological Research Projects in Henan Province (Nos. 192102110068, 182102110302, 202102110235), and the Key Scientific Research Projects Plan of Henan Higher Education Institutions (No. 17A180021). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.