Prevalence and molecular detection of Eimeria species in different types of poultry in Greece and associated risk factors

Coccidiosis is one of the most notable diseases in chickens having a high economic impact on the poultry industry worldwide. The present study is the first attempt to epidemiologically investigate Eimeria spp. distribution and associated risk factors under different housing and production systems in three major regions in Greece. Faecal samples were obtained from 42 operations (broilers, floor housed, free range and organic layers, backyard farms). A questionnaire was obtained from included operations to acquire additional information regarding farm management, location, production rate and diseases history. Positivity level was 85.7%. All seven Eimeria species were identified, and the most prevalent ones were E. acervulina (79.3%) and E. tenella (65.5%). Single-species and mixed infections were detected in 20.7% and 79.3% of the flocks, respectively. Flock size, type of outdoor area, production system and presence of respiratory disease proved significant risk factors. Flock size up to 10,000 birds correlated strongly (p = 0.02) with higher E. tenella quantities. A very strong correlation (p < 0.001) was found between the presence of respiratory disease and the average OPG level in broiler farms. Organic flocks showed higher prevalence of E. tenella (p = 0.023), while presence of vegetation at the outdoor area correlated strongly with E. brunetti (p < 0.001). Molecular analysis and correlation results in this survey give strong indications although more studies are needed to further understand the involvement of different Eimeria species in various husbandry, production and management systems, to gain more knowledge about the sustainable control of coccidia in poultry.