Seroprevalence and Risk Factors of Neospora caninum and Toxoplasma gondii in Small Ruminants in Southwest of Iran

Toxoplasma gondii and Neospora caninum are Apicomplexan intracellular protozoa with global distribution. Small ruminants play an important role as intermediate hosts for N. caninum and T. gondii, parasites of great public health concern. The main goal of the current survey was to evaluate N. caninum and T. gondii infection rate in sheep and goats of Khuzestan Province, southwest of Iran, using enzyme-linked immunosorbent assay (ELISA). In this cross-sectional study during February-April 2016, whole blood samples were taken randomly from 735 animals from 37 herds. The animals were reared under the traditional husbandry system in different parts of the province. Among 550 sheep and 185 goats, 37 (6.8%) sheep and 20 (10.8%) goats were seropositive for N. caninum and 59 (10.8%) sheep and 37 (20%) goats were seropositive for T. gondii. The incidence rates of mixed infection with N. caninum and T. gondii were 3.2% and 5.4% in sheep and goats, respectively. Seroprevalence rate of N. caninum was significantly higher in goats at <1 years of age. There was a significant association between the number of sheep infected with T. gondii and abortion (18.2%). Also, a significant correlation was detected between seroprevalence of N. caninum and T. gondii and mixed infection in goats with a history of abortion. This is the first report of IgG antibody production against N. caninumand T. gondii co-infection in small ruminants in Iran. Our findings indicated that neosporosis and toxoplasmosis may be responsible for abortion in small ruminants in this region. Therefore, further investigations are needed to improve sanitary strategies in animals’ husbandry and launching control programs.