Seroprevalence of Toxoplasma gondii infection in goats from the south-west region of Poland and the detection of T. gondii DNA in goat milk

Toxoplasma gondii (Nicolle et Manceaux, 1908) is an obligatory intracellular protozoan parasite prevalent in animals and humans worldwide having medical and veterinary importance on account of causing abortion or congenital disease in intermediate hosts, including man. Since T. gondii has already been identified in the milk of goats, Capra aegagrus hircus (Linnaeus), the possibility of acquiring infection by ingesting unpasteurised goat milk should be taken into consideration. Thus, the aim of the present study was to determine the presence of T. gondii DNA in goat milk. First, 73 goats (females) from 36 farms located in Poland were examined serologically by direct agglutination test (DAT) to estimate the T. gondii serological status. Milk samples from 60 selected lactating females were examined for the presence of T. gondii DNA by Real time PCR and nested PCR (B1 gene). To estimate the clonal type of detected T. gondii, multiplex PCR was performed using 6 markers. In DAT, positive results were found in 70% of 73 goats. Among examined 60 milk samples, 65% were positive in Real time PCR and 43% in nested PCR. It is noteworthy that 11 samples positive in PCR were collected from seronegative goats. The multilocus PCR analysis mostly revealed the occurrence of genotype III, which is relatively rare in Europe. The recorded high prevalence of anti-Toxoplasma antibodies in tested goats (70%), associated with a high prevalence of T. gondii DNA in goat milk samples (65%), indicates a potential risk of the parasite transmission through goat milk ingestion.