Epizootological characteristics of Eimeria species in chickens in the Sadarak District (Nakhchivan Autonomous Republic)

Abstract

Coccidiosis is a widespread parasitic disease in domestic chickens with significant epizootic and economic importance. It is caused by protozoa belonging to the genus Eimeria. The high resistance of the pathogen’s oocysts to environmental factors, their ability to rapidly sporulate, and their intensive reproduction ensure constant circulation of the infection within farms and contribute to the stabilization of the epizootic situation. The research goal was a comprehensive study of the epizootological characteristics of species of the genus Eimeria first reported in domestic chickens in the Sadarak District of the Nakhchivan Autonomous Republic to assess the indices of the invasion extent and intensity, and to determine the seasonal dynamics of the infection. From 2021 through 2024, 228 fecal samples collected from individual farms were tested using the flotation and McMaster methods. Coprological tests revealed the following species: Eimeria maxima (34.2%), E. tenella (30.2%), E. acervulina (29.3%), E. necatrix (22.3%), E. mitis (22.8%), E. praecox (15.7%), and E. brunetti (11.8%). The overall prevalence of infestation was 37.7%, with the number of oocysts per gram of feces (OPG) ranging from 45 to 3,100, averaging 1,285. It was found that the prevalence and intensity of infestation were significantly seasonal with higher rates in the spring and autumn. This was due to the development of optimal temperature and humidity conditions for oocyst sporulation. A relative decrease of these rates was observed in the summer and winter. Thus, the obtained results indicate that Eimeria infestation in domestic chickens in the Sadarak District is characterized by distinct seasonal dynamics with the spring and autumn periods considered to be zones of increased epizootic risk. This necessitates the optimization of preventive and anti-epidemic measures taking into account regional environmental conditions.