Comparison of Bacterial Community Structure in PM2.5 within Broiler Houses under Different Rearing Systems in China

Imran Khan,Teng Ma,Muhammad Tariq Khan,Hongfu Zhang,Lei Liu,Wenxing Wang,Xiaobin Ye,Renna Sa,Adamu Mani Isa

doi:10.3390/su14031357

Abstract

Background: In intensive poultry farming, high concentrations of indoor particulate matter (PM) impact production performance and welfare. In this study, PM2.5 level and bacterial community diversity were investigated in a multilayer cage house rearing system (CH) and a net flooring house rearing system (FH) during different growth stages to clarify the effects of the rearing systems on the diversity of airborne bacteria and help improve health management. Methods: The IC and high-throughput sequencing were used for ion composition and bacterial diversity analysis of PM2.5 collected from CH and FH. Results: The concentrations of NH3, CO2 and PM2.5 in CH were significantly lower than FH (p < 0.001) in both middle and late rearing stages. PM concentrations gradually increased with broiler growth only in FH. The water-soluble ions of PM2.5 samples had no significant difference between the two systems (p > 0.05). Firmicutes, Actinobacteria and Proteobacteria were the most abundant phyla in both the atmosphere and the broiler houses, but the composition was significantly different. The bacterial community in the broiler houses had strong correlations with temperature, humidity and PM of extremely high concentrations. Ions had stronger correlations with microbial community structure. Conclusions: The superiority of CH in environmental control over FH indicates that improved techniques in environmental control and breeding management can greatly reduce farming air pollution and improve the health management of broiler houses.

Highlights

The high concentration of particulate matter (PM) and the microbes it carries, which are discharged from intensive livestock and poultry rearing, has gradually become an important health threat to both animals and farm employees
In intensive livestock and poultry farming, indoor PM plays a vital role in pathogen transmission, respiratory diseases and allergic reactions to livestock and poultry, and has an impact on production performance and human health [13]
Numerous studies have shown that the community structure of bacterial aerosols in intensive farming is affected by many factors, including the species, feeding modes, rearing stages and seasons [14,15]

Summary

Introduction

The high concentration of particulate matter (PM) and the microbes it carries, which are discharged from intensive livestock and poultry rearing, has gradually become an important health threat to both animals and farm employees. The toxicity of these particles increases with the decrease in their size, surface area and adsorbed surface material. PM2.5 level and bacterial community diversity were investigated in a multilayer cage house rearing system (CH) and a net flooring house rearing system (FH) during different growth stages to clarify the effects of the rearing systems on the diversity of airborne bacteria and help improve health management. The bacterial community in the broiler houses had strong correlations with temperature, humidity and PM of extremely high concentrations. Conclusions: The superiority of CH in environmental control over FH indicates that improved techniques in environmental control and breeding management can greatly reduce farming air pollution and improve the health management of broiler houses

Objectives

Methods

Results

Conclusion