RISK-FACTORS ASSOCIATED WITH TRANSMISSION OF TOXOPLASMA-GONDII TO SOWS KEPT IN DIFFERENT MANAGEMENT-SYSTEMS IN TENNESSEE

Of 3841 serum samples from sows received from the Tennessee State Diagnostic Laboratory in 1991-1992, 1130 were positive for Toxoplasma gondii antibody. The total number of farms sampled was 343. The observed seroprevalence was 36% for both years. A questionnaire that dealt with herd management practices was mailed to 303 of the swine farms that were sampled; 107 (35%) responses were returned and analyzed. There was no significant difference in the seroprevalence of T. gondii in the sows on the farms of respondents and non-respondents. From the analysis of the questionnaire, sows associated with cats were 2.6 times more likely to be seropositive for T. gondii than sows that were not associated with cats. Sows kept outdoors at any time were 23 times more likely to be seropositive than sows that were kept indoors. Sows on small farms (<29 sows) were 4.5 times more likely to be seropositive than sows on large farms (> 29 sows).