Prevalence and geographic distribution of Eimeria species on commercial broiler farms in Guangdong, China

Abstract

Abstract Background Coccidiosis is one of the most frequently reported disease in chickens, exerting a substantial economic impact on the poultry industry. This study aims to conduct an epidemiological investigation into the occurrence of Eimeria species and associated risk factors under intensive management conditions across four regions in Guangdong province, China. Results A total of 394 fecal samples were obtained from 89 broiler chicken farms, culminating in an overall positivity rate of 87.06%. The results showed that the identification of all seven Eimeria species, with E. acervulina (36.29%), E. mitis (35.03%), E. tenella (34.52%) and E. necatrix (30.96%) emerging as the most prevalent species. Remarkably, single-species infections were observed in 42.86% of instances, while two to three species mixed infections were detected in 39.94% of the samples. Moreover, brid age, farming practices, control strategies, farm locations, and the presence of necrotic enteritis (NE) proved significant risk factors. Notably, a strong correlation was observed between brid age, particularly in adult birds, and the occurrence of E. necatrix (p < 0.001). A significant correlation was identified between the infection of E. necatrix or E. acervulina and the presence of NE in flocks (p < 0.001). Flocks from northern Guangdong and Peal River delta displayed higher prevalence of E. necatrix (p < 0.05). Flocks under the control programs incorporating live vaccines correlated strongly with E. tenella–E. brunetti infections (p < 0.05). Conclusions Molecular analysis undertaken in this study, coupled with the correlation results, furnishes compelling evidence. Nevertheless, it is imperative to underscore the necessity for further surveys to delve deeper into the occurrence of different Eimeria species under intensive management conditions, which will contribute significantly to our knowledge of coccidia control in poultry.