Abstract
Abstract: :
Purpose: Toxoplasma gondii is one of the world's most successful parasites and an important cause of naturally acquired intraocular infection. Since consumption or handling of meat has been identified as one of the major risk factors, prevention should be focused at the farm level. The impact of changes in animal production systems on toxoplasma infection of meat products is not yet known and was the purpose of this study. Methods: Toxoplasma seroprevalence was measured by the analysis of blood samples obtained at slaughter from pigs originating from regular indoor (n=30; 618 pigs), organic (n=16; 622 pigs) or free range (n=18; 692 pigs) farms. Approximately 20-40 animals per farm were tested. Some farms were tested repeatedly on separate occasions. Sera were screened by latex agglutination and positive serology was confirmed by the immunofuorescence antibody test and immunoblotting. Most of the farms were visited by one of us (KM), who was not aware of serology test results, to analyse various farm management variables. Results: Highest toxoplasma seroprevalence was found in free range farms (10 farms; 27 pigs) followed by organic farms (3 farms; 6 pigs), whereas none of the animals originating from regular farms were positive. Preliminary analysis indicates that cat access and rodent control were major risk factors. Conclusions: Improved animal welfare production systems are associated with a higher risk of toxoplasma infection of meat products. Slaughter house toxoplasma monitoring and alternative processing of infected animals should be implied.