Vol.:(0123456789) 1 3 Acta Parasitologica https://doi.org/10.2478/s11686-019-00140-x ORIGINAL PAPER Seroepidemiology of Toxoplasma gondii in Dairy Cows in Southeastern Brazil: Seropositive Cows on All Farms Investigated Antônio Marcos Guimarães 1  · Fábio Raphael Pascoti Bruhn 2  · Christiane Maria Barcellos Magalhães da Rocha 1  · Thatiane Helena de Araújo 3  · Cristiane Aparecida Moreira Mesquita 4 Received: 28 May 2019 / Accepted: 29 October 2019 © Witold Stefański Institute of Parasitology, Polish Academy of Sciences 2020 Abstract Purpose This study aimed to estimate the prevalence and identify the risk factors associated with the higher in-herd T. gondii seroprevalence in dairy cows in 37farms in southern Minas Gerais, Southeastern Brazil. Methods Serum samples from 1,105 dairy cows were subjected to an indirect fuorescence antibody test (IFAT 1:64) for anti-T. gondii IgG. The association existingbetween possible risk factors at the herd level and the seroprevalence were veri- fed through Generalized Estimating Equation (GEE) multiple logisticregression models. Results Anti-T. gondii antibodies were observed in 31.4% of the cows (347; 95% CI= 28.7–34.2) and on 100% of the farms (37; 95% CI= 90.6–100.0%), indicatingthat all properties possessed at least one seropositive animal. For univariate analysis, herds with seroprevalence were categorized as greater and less than30% as the outcome. The "breeding of Holstein Frie- sian cows" (p= 0.016, OR= 6.667, 95% CI= 1.500–29.628) and in an "intensive system" (p= 0.013,OR= 6.120, 95% CI= 1.394–26.876) increased the chance of the herd seroprevalence being greater than 30% by approximately six-fold. However, thesevariables did not exhibit a signifcant association (p >0.05) in the Generalized Estimating Equations (GEE) logistic regression model. Conclusions The results demonstrate that T. gondii infection is widespread among dairy cows in the south of Minas Gerais, with a wide environmental dispersion of theparasite on farms in this region. Keywords Toxoplasmosis · Bovine · Risk factors · Prevalence · IFAT Introduction Toxoplasma gondii (T. gondii) is a heterogeneous protozoan of the phylum Apicomplexa, capable of infecting several homeothermic animals, including humans [16]. This para- site, one of the major foodborne pathogens [22], is responsi- ble for toxoplasmosis, the most common parasitic zoonosis worldwide [58], whose prevalence in humans depending on the region can range from 0 to 90% [18]. The seropreva- lence is 50–80% in Brasil [9], and the frequency of clinical toxoplasmosis in humans is considered to be very high [15]. The infection is asymptomatic in most hosts. However, human T. gondii infection can cause encephalitis in immuno- compromised individuals (patients with AIDS, cancer, and transplants) and in pregnant women, severe anomalies in the fetus (cerebral calcifcation, chorioretinitis, hydrocephalus, microcephaly, intelligence defcit, blindness, epilepsy and death) due to congenital infection [30, 58]. In Brazil, the incidence of congenital toxoplasmosis exhibits wide regional variation, with an estimated incidence in the country of 0.3 per 1000 births [37]. The consumption of raw or undercooked meat, especially from goats, sheep, and pigs infected with T. gondii tissue cysts, is considered the main cause of human infection [18]. In Europe, 30–60% of cases of human infection by T. gon- dii are attributed to the consumption of under cooked meat [11]. In the USA, foodborne toxoplasmosis is only surpassed * Antônio Marcos Guimarães amg@ufa.br 1 Department of Veterinary Medicine, Federal University of Lavras, Lavras, MG, Brazil 2 Preventive Veterinary Department, Zoonoses Control Center, Faculty of Veterinary Medicine, Federal University of Pelotas, Capão do Leão, RS, Brazil 3 Lavras, MG, Brazil 4 Postgraduate Program in Veterinary Science, Federal University of Lavras, Lavras, MG, Brazil