Cyathostomin faecal egg counts in horse farms from Central Italy.

Cyathostomins, or 'small strongyles, are the most important equine helminths because of their worldwide distribution, spread of anthelmintic-resistant populations, and pathogenic impact. The so-called 'selective treatment' of those animals exceeding a certain faecal egg count (FEC) has recently been proposed to implement cyathostomin control programmes. The present study evaluated the extent of egg shedding in 475 horses living in 12 farms from 3 regions of Italy. All examined farms and 224 horses (47.6%) were positive for cyathostomins. 138 horses (28.8%) scored positive for cyathostomin FECs with a range of eggs-per-gram of faeces (epg) values of 50-2,150. Further 86 horses (18.1%) were positive only under qualitative microscopy (i.e. < 50 epg). Of the animals with a FEC > 50 epg, 81 (17%) and 57 (12%) showed values of 50-200 and > 200 epg, respectively. The findings from this study demonstrated a reduced presence of high-shedding horses compared to results obtained in previous years in the same study areas, despite overlapping climate features in the previous 5 years. A continuing monitoring of epidemiological and biological features of horse cyathostomin infection is crucial for planning intervention programmes aimed to maintaining animal health and preserving the efficacy of parasiticides.