Seroepidemiology of Toxoplasma gondii in Dairy Cows in Southeastern Brazil: Seropositive Cows on All Farms Investigated

• Published in: Acta parasitologica Vol. 65; no. 3; pp. 628 - 635
• Main Authors: Guimarães, Antônio Marcos, Bruhn, Fábio Raphael Pascoti, da Rocha, Christiane Maria Barcellos Magalhães, de Araújo, Thatiane Helena, Mesquita, Cristiane Aparecida Moreira
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01-09-2020; Springer Nature B.V
• Subjects: Animal husbandry; Animal Systematics/Taxonomy/Biogeography; Antibodies; Biomedical and Life Sciences; Biomedicine; Breeding; Dairy cattle; Dairy farming; Dairy farms; Ecology; Estimation; Farms; Fluorescence; Immunoglobulin G; Medical Microbiology; Microbiology; Original Paper; Parasites; Parasitology; Protozoa; Regression analysis; Regression models; Risk analysis; Risk factors; Seroepidemiology; Brazil; IFAT; Prevalence; Bovine; Toxoplasmosis; Risk factors
• ISSN: 1230-2821; 1896-1851
• DOI: 10.2478/s11686-019-00140-x

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 37 farms in southern Minas Gerais, Southeastern Brazil.
Methods
Serum samples from 1,105 dairy cows were subjected to an indirect fluorescence antibody test (IFAT 1:64) for anti-T. gondii IgG. The association existing between possible risk factors at the herd level and the seroprevalence were verified through Generalized Estimating Equation (GEE) multiple logistic regression 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%), indicating that all properties possessed at least one seropositive animal. For univariate analysis, herds with seroprevalence were categorized as greater and less than 30% as the outcome. The "breeding of Holstein Friesian 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, these variables did not exhibit a significant 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 the parasite on farms in this region.