Prevalence and risk factor analysis of equine infestation with gastrointestinal parasites in Israel

The horse is a host for a large number of intestinal helminthic parasites. This study was designed as a survey for the prevalence, species distribution and potential risk factors of equine intestinal helminth parasites among horses in Israel. Fecal floatation and egg counts were performed on 485 fecal samples collected from 403 horses (mostly adults) at 30 farms across Israel. Strongyle eggs were found in 116/485 (24%) of the samples from 18/30 (60%) farms, of which 44 (38% of positive samples, 9% of the total population) were highly infested (over 500 eggs/gm feces). Ascarids were found in 26/485 (5%) samples from 10/30 (33%) farms, 7 (27% of positive samples, 1.4% of the total population) of which were highly infested. Singular flatworm eggs (family Anoplocephala) were detected in two samples. Risk factors significantly (p<0.005) associated with Strongyle infestation by the univariate statistical analysis were the farm, geographical location, age of the horse and breed, and the time of last deworning treatment. Season, horse gender, horse age, and housing were significantly associated with ascarid infestation.Infestation with gastrointestinal helminths in Israel appears to be low, and resistance against anthelminthics in adult horses is probably uncommon. These findings should lead to re-investigation and re-evaluation of deworming regimes in Israel recommended for adult horses in equine facilities in areas with low infestation rates.