RESUMO
Toxoplasma gondii is a widespread protozoan parasite that causes infections in animals and humans. The presence of tissue cysts in cattle musculature evidences their epidemiological significance in transmission to humans. The present study aimed to evaluate the seroprevalence of and risk factors of T. gondii seropositivity in beef cattle in the municipality of Unaí, Minas Gerais state, Brazil. Bovine blood samples (n = 612) were collected from 31 herds. Risk factors associated with the animal-level and herd-level seroprevalence were analysed using a questionnaire that investigates the epidemiological aspects of toxoplasmosis. A search for anti-T. gondii antibodies was performed by means of an indirect fluorescent antibody test (IFAT). Analysis of 612 samples showed 369 animals positive for anti-T. gondii antibodies (IFAT ≥64), with a seroprevalence of 60.29% (95% confidence interval (CI): 56.35-64.10). The herd-level seroprevalence was 96.77% (95% CI: 79.00-99.58). Applying a multivariate logistic regression analysis, a test of the association between seroprevalence of T. gondii infection and the potential predictors showed that cats (domestic or wild) with access to the drinking water of cattle were a significant (P = 0.001) predictor. The seroprevalence of T. gondii in cattle destined for human consumption is widely distributed throughout the entire study area. Thus, integrated control measures and strategies are suggested to prevent T. gondii infection in cattle.
Assuntos
Doenças dos Bovinos , Toxoplasma , Toxoplasmose Animal , Animais , Anticorpos Antiprotozoários , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Fatores de Risco , Estudos Soroepidemiológicos , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/parasitologiaRESUMO
The objective of this study was to identify Anaplasma marginale strains in dairy heifers from farms with a history of anaplasmosis in the northwest region of the State of Minas Gerais, Brazil. Among the examined animals of the four farms, the overall prevalence total of A. marginale was 55.7 % for gene msp5 and 36.7 % for blood smear. Thirty DNA samples (from 24 asymptomatic and six symptomatic animals) positive for A. marginale msp1α were sequenced to study genotype and strain diversity. The majority (28/30) were the E genotype, followed by C (1/30) and G (1/30). Thirteen different strains were found: α-ß-F-F-F (nine animals), 13-27-27 (three animals), τ-27-18 (three animals), α-ß-ß- BRA1-31 (three animals), α- 22-1318 (three animals), 80-F-F- F-F (three animals), and α -22-13-13, α-ß-ß-Ð, M-φ-φ-φ-φ-F, 42-25- 25-31, Q-Q-Q-M, B-Q-B-Q-B-M, and 16-17-F-F (one animal each). A new structure repeated in tandem was described and named BRA 1 (TDSSSASGVLSQSGQASTSSQLG). The α-ß-F-F-F strain was present in all animals with acute anaplasmosis and in three animals asymptomatic. Thus, although 13 strains were observed in the animals evaluated, only the α-ß-F-F-F strain was identified during occurrence of acute disease and mortality, we suggest that this strain has important pathogenicity for calves in northeastern Minas Gerais.