The present study describes the detection of anti-T. gondii antibodies (IgG and IgM) in sequential serum samples from lambs and their mothers, without clinical signs. IgG antibodies were quantified by indirect imunofluorescence (IFI) and indirect hemaglutination (HAI). IgM was detected using HAI 2- mercaptoethanol, by commercial kits. Titers higher than 16 for hemaglutination and 20 for imunofluorescence were considered positive. 247 sera samples were analysed and, after a three months interval, more 120 sera samples from their lambs were studied. There were 175 sheeps in one property and 72 sheeps in the other, both situated in the rural area of Rosário do Sul county, RS, Brazil. Through sero logical analysis were detected 22 lambs (18.3%) who showed titers in the first test, which declined and also negativated the imunological response in the second test, denot ing antibodies passive transference.Only at four lambs (3.3%), whose mothers presented early infection, IgG titers increased from first to second test, suggesting possible congenital transmission of T. gondii.
Toxoplasma gondii; sheep; congenital transmission; IgG; IgM; Rosário do Sul
