TDK conference 2017

Among the intestinal parasites of horses, the large- and/or small strongyles can occur most often. Hungarian horse keepers more or less regularly guard against these nematodes, but they don’t know the extent of the infections in the horses, neither the necessity of the disinfections, nor the effectiveness of the used product. The goal of our examinations was to establish the extent of the colonic worm infections despite the antihelmintic treatments in the researched stud farms, and in the light of the results, is it better to switch to the so called selective antihelmintic therapy, and furthermore, are there any stables, where drug-resistent small strongyles can be found.

Between 2016 December and 2017 May, fecal samples were collected from 9-62, all together 201 horses from 7 riding-schools in Pest county, and information about keeping conditions and the anthelmintic treatment of the horses were recorded. During the laboratory studies McMaster, larval culture methods and Baermann technique were used.

86 horses (42,8%, 95%,CI: 36,0-49,8) had strongyle-like eggs in their samples. The eggs per gram (EPG) value was 50-1800 per horse. The prevalence of colonic worm infection of the farms ranged from 15,8% to 61,2%. From the stables with small strongyles infection in Perbál, 17 horses (34,7%) had more than 200 EPG per sample. Two groups from these horses were formed, and fecal egg count reduction test (FECRT) was done, to establish the resistance of the small strongyles against the ivermectin that used for antihelmintic treatment.

According to the findings of our examinations, and the international aspects, it can be concluded that it would be practical to use the selective antihelmintic therapy, and treat only less than the third of the horses. The small strongyles in the horses of Perbál didn’t become resistante against ivermectin, because the EPG value decreased 99% from the first day of the treatment to the 14. day.