Polystyrene exposure induces lamb gastrointestinal injury, digestive disorders and inflammation, decreasing daily gain, and meat quality

Xiao Chang; Yan Li; Yujie Han; Yi Fang; Hai Xiang; Zijiao Zhao; Bao Zhao; Rongzhen Zhong

doi:10.1016/j.ecoenv.2024.116389

Polystyrene exposure induces lamb gastrointestinal injury, digestive disorders and inflammation, decreasing daily gain, and meat quality

Ecotoxicol Environ Saf. 2024 Apr 23:277:116389. doi: 10.1016/j.ecoenv.2024.116389. Online ahead of print.

Authors

Xiao Chang¹, Yan Li², Yujie Han¹, Yi Fang³, Hai Xiang¹, Zijiao Zhao⁴, Bao Zhao⁴, Rongzhen Zhong⁵

Affiliations

¹ Jilin Province Feed Processing and Ruminant Precision Breeding Cross regional Cooperation Technology Innovation Center, Jilin Provincial Laboratory of Grassland Farming, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
² College of Veterinary Medicine, Hebei Agricultural University, Baoding 071000, China.
³ Key Laboratory of Animal Production, Product Quality and Security, Ministry of Education, Jilin Agricultural University, Changchun 130118, China.
⁴ Jilin Province Feed Processing and Ruminant Precision Breeding Cross regional Cooperation Technology Innovation Center, Jilin Provincial Laboratory of Grassland Farming, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China.
⁵ Jilin Province Feed Processing and Ruminant Precision Breeding Cross regional Cooperation Technology Innovation Center, Jilin Provincial Laboratory of Grassland Farming, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China. Electronic address: zhongrongzhen@iga.ac.cn.

PMID: 38657458
DOI: 10.1016/j.ecoenv.2024.116389

Abstract

Microplastics (MPs), recognized as an emerging environmental menace, have been extensively investigated in both marine and terrestrial fauna. This study is comprehensive to investigate how polystyrene (PS) affects ruminant animals. The experimental design comprised 24 individually housed lambs, divided into a CON group (diet without PS) and three PS-exposed (25 μm, 50 μm, 100 μm) groups, each with six lambs, the exposure of PS was 100 mg/day, and the duration of exposure was 60 days. The study yielded noteworthy results: (ⅰ) PS leads to a decrease in average daily gain along with an increase in feed conversion rate. (ⅱ) PS decreases rumen ammonia nitrogen. The rumen microbiota diversity remains consistent. However, the relative abundance of Bacteroidetes and Actinobacteria increased in the PS-exposed groups, while the relative abundance of Coriobacteriales_incertae_Sedis and Prevotellaceae_YAB2003_group decreased. (ⅲ) PS leads to decrease in hemoglobin, thrombocytocrit, and albumin levels in lamb blood, thus triggering oxidative stress accumulation, along with swelling of the kidneys and liver. (ⅳ) PS inflicts severe damage to jejunum, consequently impacting digestion and absorption. (ⅴ) PS reduces meat quality and the nutritional value. In conclusion, PS-exposure inhibited lambs' digestive function, adversely affects blood and organs' health status, reducing average daily gain and negatively influencing meat quality. PS particles of 50-100 μm bring worse damage to lambs. This research aims to fill the knowledge void concerning MPs' influences on ruminant animals, with a specific focus on the meat quality of fattening lambs.

Keywords: Lamb; Meat quality; Microplastics; Polystyrene; Rumen fermentation.