Infection Frequency and Allelic Variants of Toxoplasma gondii in Wildlife from the Panama Canal Zone

Panama has a large number of wild animal species, which could host a highly diverse amount of genetic variants of Toxoplasma gondii (T. gondii). In this context, we highlight the importance of understanding the population structure of T. gondii in Panamanian wildlife and the genetic variants that can be rapidly transferred to domestic environments. This study analyzed the infection frequency and allelic composition of T. gondii in different tissue samples from wild animals. The infection frequency was measured by the PCR technique using the B1 gene as a molecular marker. The results showed a high frequency (65.6%) of infection in tissue samples collected from 221 wild animals. Stratified analyses for bird and mammal samples showed positivity rates of 67.2% and 70.12%, respectively, with no statistically significant differences. Infection frequency was also measured in five types of organs (brain, liver, heart, lung, and skeletal muscle), which showed homogeneous frequencies. The genetic diversity of the T. gondii population contained in the tissues of wild animals was analyzed by the Multilocus Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) technique, using five genes called SAG1, SAG2, SAG3, GRA6, and Apico. This analysis revealed the presence of alleles of these genes corresponding to T. gondii lineages I, II, and III. Allele III was only identified with the Apico gene in a single reptile individual analyzed. Our findings indicated diverse allelic distribution at the analyzed loci, suggesting that the tissues were probably infected by non-archetypal individuals of T. gondii.