Prevalence of IgG and IgM antibodies specific to Toxoplasma gondii in cats.

IgG and IgM antibodies specific to Toxoplasma gondii were determined simultaneously by IFAT in cats. Group 1 included 357 cats with various diagnoses, but negative for FeLV and FIV. Specific IgG antibodies in titres ranging from 10 to 2560 (mean 247) were detected in 61.3% animals, specific IgM antibodies were found only in one cat (0.28%) in titre 1:40 showing an IgG titre of 160. Oocyst shedding was demonstrated in one cat (0.28%) showing an IgG titre of 1:40. Group 2 included 33 cats positive for FeLV or FIV. IgG antibodies in titres ranging from 10 to 640 (mean 101) were found in 63.6% cats. Neither IgM antibodies nor shedding of T. gondii oocysts were detectable. Clinically unapparent toxoplasmosis, manifested by the presence of IgG antibodies is frequent in cats; the opportunistic character of the infection is important.