Avaliação sorológica de anticorpos da classe IgG para Toxoplasma gondii em soros de ovinos da região da grande Porto Alegre/RS, através das técnicas de hemaglutinação indireta (HAI) r imunofluorescência indireta (IFI).

Toxoplasmosis is a serious zoonosis. It is a common infection in animals caused by a parasite called Toxoplasma gondii. Human infection occurs mainly for ingestion of meat contaminated with T. gondii cysts. A high prevalence rate of toxoplasmosis is found in sheep cattle all over the world, being the consumption of food and water contaminated with oocystes the major source of infection of the species. In ovine, toxoplasmosis can be assymptomatique or cause reproduction disorders, especially abortions, which leads to significant economic losses.With the objective of providing data about the frequency of T. gondii antibodies in sheep from the Greater Porto Alegre area, we estimated the frequency of IgG class antibodies to T. gondii in sheep sera. The techniques employed were the Indirect Hemagglutination Technique (HAI) and the Indirect Imunofluorescence Test (IFI). The estimated frequency of antibodies to T. gondii in a sample of 250 sheep sera was 13,6% (HAI), and 15,2% (IFI). The sample was stratified into two experimental groups, according to gender and age. In group one, composed by 127 males, 4,8% were HAI positive, and 7,6% were IFI positive, whereas in the group composed by 123 females, 8,8% were HAI positive, and IFI 7,6%. Concerning age group, there were 11 HAI positives (4,4%) among the animals with less than one year of age, and 23 HAI positive (9,2%) among the animals over one year, totalizing 34 animals. For the IFI technique, the results obtained showed 19 (7,6%) young sheep and 19 (7,6%) adults in 38 animals analyzed. The co-positivity between the techniques was 55,26% and the co-negativity was 93,865. Total agreement was 88% while the Kappa index calculated was 0,513.