Risk factors associated with the epidemiology of Toxoplasma gondii in cattle and buffaloes in the state of Para, Brazil

Toxoplasma gondii is an obligate intracellular protozoan that parasitizes several hosts worldwide, of which cats are definitive hosts. The objective of this study is to evaluate the risk factors associated with the epidemiology of T. gondii in cattle and buffaloes in the state of Para, Brazil. A total of 2,070 bovine samples (1,749 cattle and 321 buffaloes) were evaluated in 100 rural properties distributed in 51 municipalities from all mesoregions of the state. The evaluated risk factors were animal gender, type of farm, and number of cats in the properties. The serological prevalence of T. gondii was evaluated using the indirect enzyme immunoadsorption assay (iELISA). The samples with a sample/positive (S/P) ratio >= 0.5 were considered positive and analyzed using the indirect immunofluorescence assay (IFA). The samples diluted at 1: 64 were considered positive. The chi-square test with a level of significance of 5% and the odds ratio (OR) with a confidence interval of 95% was applied. The data were analyzed using BioEstat software version 5.0. The prevalence of T. gondii in bovines was 35.79% and 45.12% in ELISA and IFAT, respectively. The prevalence was 34.48% and 44.14% in cattle and 42.99% and 50.47% in buffaloes using ELISA and IFA, respectively. The mesoregion with the highest prevalence of infection was Marajo Island, corresponding to 42.86% (129) and 50.5% (152) in ELISA and IFA, respectively. In buffaloes, the prevalence of T. gondiiusing ELISA was higher in males (p < 0.05) in the two age groups. In contrast, the prevalence of T. gondii using IFA was higher in males in the age group 13 to 24 months (p < 0.05). The type of farm did not affect the prevalence of T. gondii in cattle (p > 0.05). However, the presence of cats strongly affected the occurrence of infection in cattle. These results demonstrate the high levels of anti-T. gondii antibodies in cattle and buffaloes in Para and this may be a public health problem. Furthermore, the presence of cats is a risk factor for infection with T. gondii in these species in Para.