Toxoplasma gondii in free-range chickens from Bahia State: serology, meta-analysis, associated factors and spatial analysis

Introduction: Free-range chickens have been studied extensively as environmental contamination markers by Toxoplasma gondii, a cat Coccidia, which causes important zoonosis and an agent of abortion in production animals. Objective: The objective of this study was to evaluate the frequency of infection of chickens reared in rural properties of Feira de Santana, Bahia, Brazil, and the factors associated with rates of positivity. Methods: A total of 290 blood samples were obtained from birds of 15 properties and examined by modified agglutination test in dilutions equal to or greater than 1:25. Data on the conditions of birds rearing and contact with other animals were collected. Sample collection was conducted between March and September 2016. Results: The Frequency of reagent sera (49.7%) in Gallus gallus can be considered similar to other Brazilian works, however, the titers found were less than or equal to 100 in 90% of birds with acute infection. Conclusion: Among the factors surveyed, the area of origin of the samples, the presence of cats, cats fed with raw meat, and the absence of dogs with less than six months were significantly associated with rates of infection of birds by logistic regression. Spatial cluster analysis showed an area of concentration of infected birds.