Exposure to Protozoan Parasites in Donkeys

Domestic donkeys (Equus africanus acinus) in Israel are used as burden animals, riding animals, as pets and in petting zoos. There is little regulation concerning the management or health of donkeys and data of their exposure to infectious diseases is scarce.

The aim of this study was to evaluate the exposure of donkeys to a number of protozoan parasites with possible zoonotic potential for humans or other animal species: Toxoplasma spp. may cause abortions in women as well as in cattle and small ruminants; Neospora spp. is a major cause for abortions in cattle, it may also cause neurologic disease and recent data suggest that it may also clinically affect humans and horses; Besnoitia spp. may cause skin lesions in equines and cattle and infertility in bulls; Theileria equi and Babesia caballi may cause equine piroplasmosis which manifests in hemolysis and anemia in equids.

Blood and serum were collected from 98 donkeys in 7 farms. Exposure to Toxoplasma spp., Neospora spp. and Besnoitia spp. was evaluated using immunoflorescent antibody test (IFAT). Molecular prevalence of T. equi and B. caballi was evaluated using species-specific PCR. Risk factors for exposure were assessed using χ², Fisher’s exact or t-test, as appropriate.

Antibodies against Toxoplasma spp., Neospora spp. and Besnoitia spp. were detected in 65 (66%), 69 (70%) and 54 (55%) donkeys respectively. The farm was associated with exposure to Toxoplasma spp. (P=0.011) and Besnoitia spp. (P<0.001) and age was associated with exposure to Besnoitia spp. (P=0.022). T. equi DNA was detected in 31 (32%) donkeys, with the farm (P<0.001) and sex (more in males, P=0.007) significantly associated with carriage. B. caballi was not detected.

This study provides preliminary data of high exposure to Toxoplasma and Neopspora spp., highlighting the significance of donkeys as potential reservoirs for veterinary and potentially zoonotic diseases.