Concentration and size distribution of particulate matter in a new aviary system for laying hens in China

ABSTRACT

Particulate matter (PM) from poultry production facilities may strongly affect the health of animals and workers in the houses, and PM emitted to the ambient air is an important pollution source to the surrounding areas. Aviary system is considered as a welfare friendly production system for laying hens. However, its air quality is typically worse as compared with conventional cage systems, because of the higher PM concentration of indoor air and other airborne contaminants. Furthermore, PM’s physical property, which has a direct impact on the penetration depth into the lungs of the birds and humans, is largely unknown for the aviary system. Therefore, a systematic method was utilized to investigate the characteristics of particles in the aviary house with large cage aviary unit system (LCAU) in Beijing, China. For the field measurements, three measuring locations were selected with two inside and one outside the house with LCAU to continuously monitor PM concentrations and collect the samples for particle size distribution (PSD) analysis. Results showed that PM_2.5, PM₁₀, and total suspended particulate (TSP) concentrations averaged at 0.037 ± 0.025 mg/m³, 0.42 ± 0.10 mg/m³, and 1.92 ± 1.91 mg/m³, respectively. Particle concentrations increased from October to December due to less ventilation as the weather got colder, and were generally affected by stocking density, ventilation rate, birds’ activities, and housing system. Meanwhile, indoor PM_2.5 concentration was easily impacted by the ambient air quality. Mass median diameter (MMD) and mass geometric standard deviation (MGSD) of the TSP during the measurement were 18.92 ± 7.08 μm and 3.11 ± 0.31, respectively. Count median diameter (CMD) and count geometric standard deviation (CGSD) were 1.94 ± 0.14 μm and 1.48 ± 0.08, respectively. Results indicated that the aviary system can attain a good indoor condition by suitable system design and environment control strategy.

Implications: Indoor PM_2.5 concentration of the layer house can be significantly affected by ambient air quality when the air quality index (AQI) was larger than 100. PM_2.5 and PM₁₀ concentrations of the layer house with a LCAU system were comparable to the cage system. TSP concentration was higher, and PM size was larger than most of the cage system. System design, larger space volume, and higher ventilation rate were the main influence factors. Good indoor environment of the aviary system can be achieved through the reasonable design of the production system and appropriate environment control strategy.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary material

Supplementary material data for this article can be accessed here.

Additional information

Funding

This work was supported by the National Key R&D Program Project of China [grant number 2017YFD0701602].

Notes on contributors

Zongyang Li

Zongyang Li is a Ph.D. Student at the Department of Agricultural Structure and Bioenvironmental Engineering, China Agricultural University, Beijing, China.

Chaoyuan Wang

Chaoyuan Wang, Baoming Li, Zhengxiang Shi, Weichao Zheng, and Guanghui Teng are professors in the Department of Agricultural Structure and Bioenvironmental Engineering, College of Water Resources and Civil Engineering, China Agricultural University, Beijing, China.

Baoming Li

Chaoyuan Wang, Baoming Li, Zhengxiang Shi, Weichao Zheng, and Guanghui Teng are professors in the Department of Agricultural Structure and Bioenvironmental Engineering, College of Water Resources and Civil Engineering, China Agricultural University, Beijing, China.

Zhengxiang Shi

Chaoyuan Wang, Baoming Li, Zhengxiang Shi, Weichao Zheng, and Guanghui Teng are professors in the Department of Agricultural Structure and Bioenvironmental Engineering, College of Water Resources and Civil Engineering, China Agricultural University, Beijing, China.

Weichao Zheng

Chaoyuan Wang, Baoming Li, Zhengxiang Shi, Weichao Zheng, and Guanghui Teng are professors in the Department of Agricultural Structure and Bioenvironmental Engineering, College of Water Resources and Civil Engineering, China Agricultural University, Beijing, China.

Guanghui Teng

Chaoyuan Wang, Baoming Li, Zhengxiang Shi, Weichao Zheng, and Guanghui Teng are professors in the Department of Agricultural Structure and Bioenvironmental Engineering, College of Water Resources and Civil Engineering, China Agricultural University, Beijing, China.