Sera samples derived from 200 finishing pigs from confinement herds, hibrids were used. The sera were collected in abattoirs of me North-west region of Rio Grande do Sul state, Brazil. Tested for antitoxoplasmics immunoglobulins using the Indirect Hemagglutination test (IHA). A relation of the positive sera samples and formation of retinochoroiditis in histological studies with Hematoxilin-Eosin (HE) staining was stablished. The prevalence rate of seropositivity toxoplasmic infection was 18%, starting from titers 1:64. The titer varied from 1:64 (39%); 1:128 (5.5%); 1:256 (39%); 1:512 (5.5%); 1:1024 (11%). Histophathogical alterations findings in 3 positive sera samples were: retinal atrophy (1:64; 1:256) and macular hiperemy (1:256). Retinochoroiditis lesions were not found in the present study.
Antitoxoplasmics immunoglobulins; retinochoroiditis; indirect hemagglutination; swine