Dietary High Zinc Oxide Modulates the Microbiome of Ileum and Colon in Weaned Piglets.

Ting Yu,Hang Lv,Zhuang Chen,Ruowei Feng,Zongyong Jiang,Jinsong Xu,Lei Gao,Cui Zhu,Qingfeng Zhu,Shicheng Chen

doi:10.3389/fmicb.2017.00825

Abstract

Dietary zinc oxide (ZnO) at pharmacological level has been widely used to prevent and treat diarrhea in weaning piglets. Despite its importance for promoting animal health and performance, the influence of microbiome profiles in intestinal tracts by ZnO needs to be comprehensively investigated. In this study, we conducted a comparative microbial community analysis in the ileum and colon of piglets fed by either control diet, high ZnO (3,000 mg/kg) supplement or antibiotics (300 mg/kg chlortetracycline and 60 mg/kg colistin sulfate) supplement. Our results showed that both high dietary ZnO and in-feed antibiotics supplementations significantly increased 5 phyla of Spirochaetes, Tenericutes, Euryarchaeota, Verrucomicrobia, TM7, and reduced 1 phyla of Chlamydiae in ileal digesta. The relative abundance of opportunistic pathogens Campylobacterales were decreased while Enterobacteriales were increased in ZnO or antibiotics-supplemented group when compared to the control. In the colon, the phyla Euryarchaeota, the genus Methanobrevibacter, and the species Methanobrevibacter smithii were drastically increased by high dietary ZnO supplementation when compared with other groups. The microbial functional prediction analysis showed that high dietary ZnO and in-feed antibiotics had a higher abundance of transporter pathway enrichment in the ileum when compared with the control. While in the colon high dietary ZnO had a higher abundant enrichment of methane metabolism involving energy supply when compared with other groups. Both high dietary ZnO and antibiotics increased the microbiota diversity of ileal digesta while they decreased the microbiota diversity of the colonic digesta. Collectively, these results suggested that dietary ZnO and in-feed antibiotics supplementations presented similar effect on ileal microbiota, and mainly affected the non-predominant microbiota.

Highlights

The piglets at early weaning stage are subjected to nutritional, physiological, and psychological stressors, leading to post-weaning diarrhea (PWD) and consequent growth retardation (Pluske et al, 1997; Lallès et al, 2007)
We provided an in-depth analysis of the bacterial taxa compositions and compared the effects of the zinc oxide (ZnO)
Our results showed the piglets fed the diets supplemented with high ZnO had similar microbiome profiles in the ileal and colonic digesta compared to those in the antibiotics group

Summary

Introduction

The piglets at early weaning stage are subjected to nutritional, physiological, and psychological stressors, leading to post-weaning diarrhea (PWD) and consequent growth retardation (Pluske et al, 1997; Lallès et al, 2007). Microbiome of Ileum and Colon in Weaned Piglets industry due to the increase of antibiotic resistance and its potential contaminations to human (Barton, 2000; Bach Knudsen, 2001; Smith et al, 2002). High ZnO was assumed to reduce the incidence of diarrhea by lowering the counts of pathogenic bacteria (Sales, 2013), while some studies have showed that ZnO increased the population of Enterobacteriales (Hojberg et al, 2005; Pieper et al, 2012). Another study by denaturing gradient gel electrophoresis (DGGE) showed that high dietary ZnO supplementation resulted in a significant increase in most bacterial diversity in the ileum while no influence on lactic acid bacteria was observed (Pieper et al, 2012)

Methods

Results

Conclusion