Leila Gatti Sobreiro

Toxoplasma gondii: estudo soro-epidemiológico de suínos da região Sudoeste do Estado do Paraná

This study evaluated the seroprevalence of toxoplasmosis in pigs bred and slaughtered for human consumption. The frequency of the antibody anti-Toxoplasma gondii was investigated in 408 animals from distinct piggeries of 25 cities in the southwestern region of the state of Parana, Brazil. Serum samples were examined for IgG antibodies specific for T. gondii through the indirect fluorescent antibody test (IFAT). A frequency of 25.5% of serum samples tested positive for dilutions equal to or greater than 1:64. Statistically significant were not observed in relation to sex and age of the animals. The highest antibody level observed was 4,096 (3.0%) and the most frequent was 64 (74%), suggesting that a chronic infection occurred in the population. The high prevalence of the infection found in the swine herds of this region suggests that these herds can be a source of infection for individuals who typically consume this type of raw or badly cooked meat.

Occurrence of infection with Toxoplasma gondii and factors associated with transmission in broiler chickens and laying hens in different raising systems

Toxoplasmosis is a zoonotic disease caused by the protozoan Toxoplasma gondii. The aim of the present study was to determine the occurrence and identify the risk factors associated with transmission of T. gondii to chickens raised in different systems (free-ranged and conined) to produce eggs or meat. The 810 animals were allocated in two experimental groups according to the production system purpose: 460 broiler chickens (Group 1) and 350 layer chickens (Group 2). In order to analyze the possible factors involved in T. gondii infection in the chickens, an epidemiological questionnaire was developed for all properties.The serological detection of anti-Toxoplasma gondii antibodies was performed by Indirect Immunoluorescence (IFAT) and by Enzime Linked Imunossorbent Assay (ELISA). Since the agreement index (kappa) between these two serological techniques was considered high, 21.2% of the 810 animals were considered reactive. In Group 1, 12.2% (56/460) were positive, while in the Group 2 the positivity rate was 33.1% (116/350). The production system may be inluencing the seropositivity of the animals in both groups. However, only in Group 2 it was possible to notice a statistically signiicant relationship between the breeding system and the frequency of positive sera. This result indicates that, at least for laying hens, the production system is directly involved in T. gondii infection. The contact with cats in Group 1 did not inluence the distribution of seroreactive animals, but in Group 2 a signiicant relationship was observed. The occurrence of anti-T. gondii antibodies was high in both groups (broiler and posture chickens). Free-ranged chickens raised for egg production proved to be the most exposed group to the T. gondii infection. This can be related to the fact that these animals stay for longer periods in the farms, in direct contact with possibly contaminated soil by the presence of domestic cats. INDE.