Toxoplasma gondii

Seroprevalence of Toxoplasma gondii

In general, antibodies to Toxoplasma gondii were found in 49 (6.8%) of the 721 serum samples screened using LAT. In northeastern Thailand, T. gondii infection was most prevalent (11.1%) among buffaloes raised in Roi Et Province, while the lowest prevalence value observed was 1.4%, in Buri Ram Province. Seroprevalence in buffaloes from Surin and Sakon Nakhon was similar at 5.5% and 4.9%, respectively. There was a seroprevalence of 3.4% in buffaloes from Si Sa Ket and 6.5% of buffaloes in Ubon Rachathani were infected with T. gondii (Fig. 1).

The majority of the samples for T. gondii presented low LAT titres. The most common titre was 1: 64 (66% of the positive samples). The remaining 25% of samples corresponded to the titre 1: 128. Only one and two positive samples showed 1: 1,024 and 1: 256 titres, respectively. No sample was positive at the moderate titre of 1: 512 (Table 1). In Songkhla province, titres of either 1: 128 or 1: 256 accounted for 28.6% of positive serum samples. While 21% of positive sera were recorded for the 1: 64 titre, only one and two were observed in 1: 1,024 and 1: 512 titres, respectively (Table 1).

Of the 294 farms, 39 had serological evidence of T. gondii infection (13.3%). They were widely distributed among all investigated provinces: Ubon Rachathani (8/59, 14%), Roi Et (9/58, 16%), Si Sa Ket (2/22, 9%), Surin (4/28, 14%), Buri Ram (1/22, 5%), Sakon Nakhon (9/98, 9%), and Songkhla (6/7, 86%).

Considering age, only 2% of the calves (aged less than 1 year) were positive for T. gondii infection, whereas buffaloes aged 1–5 years and buffaloes older than 5 years presented prevalence values of 6.3% and 8.7%, respectively. The prevalence of infection was 3.8% for male buffaloes and 7.3% for the females. However, these differences in prevalence values were not significant (Table 2). The seroprevalence of the disease was significantly (p = 0.002) higher in water buffaloes from the southern province (14.7%) than from the provinces in the northeast (5.6%) (Table 2).