Isolation and characterization of Toxoplasma gondii genotypes from goats at an abattoir in Okinawa.

Toxoplasma gondii genotypes were isolated and characterized from cephalic muscle samples collected from 24 goats slaughtered at an abattoir in Okinawa between 2008 and 2009. Of the 24 samples assayed using latex agglutination, 18 were seropositive, 2 were pseudo-positive, and 4 were seronegative against T. gondii antibodies. The samples were then inoculated into laboratory mice to isolate the parasite. Among the isolated samples, 13 (72.2% of the 18 seropositive strains in the latex agglutination assay) were seropositive, 1 (50%) was pseudo-positive, and none were seronegative. However, after being frozen and stored at -20ºC, all samples were found to be T. gondii-free. Of the 14 isolates of the GRA6 genotype, 6 were of type I, 7 were of type II, and 1 was of type III; the genotype distribution ratio was similar to that of T. gondii strains isolated from locally raised pigs. Moreover, no sulfonamide-tolerant dhps gene mutant of T. gondii was detected.