Coprological prevalence and intensity of helminth infection in working horses in Lesotho

Abstract

This study aimed to (1) estimate infection prevalence of strongyle, Oxyuris equi and Parascaris equorum species and the intensity of infection with strongyles in working horses in lowland Lesotho and (2) investigate associations between infection and horse age, sex and owner-reported use of anthelmintics. In a cross-sectional survey, fresh faecal samples were obtained from 305 randomly selected horses and worm egg counts performed using a validated field laboratory kit. Details of anthelmintic use were collected using a standardised face-to-face owner questionnaire. Infection prevalence estimates for each species were calculated, as were infection intensity estimates for strongyle species. Logistic regression was used to investigate associations between exposure variables and infection status/intensity. Prevalence of strongyle infection was 88.2%; 11.8% of horses were not infected and infection intensity was low (1-500 eggs per gram (epg)) in 19.7%, medium (501-1,000 epg) in 19.7%) and high (>1,001 epg) in 48.8%. Decreasing strongyle infection intensity was associated with the use of proprietary equine anthelmintic products (OR 0.18, 95%CI 0.11-0.30, p<0.0001). Prevalence of O. equi infection was 6.2%; the odds of infection with this parasite decreased with increasing horse age (OR 0.84, 95%CI 0.72-0.97, p = 0.02). P. equorum infection prevalence was 21.6%; no statistically significant associations with the investigated exposure variables were found. In conclusion, strongyle infection is endemic in working horses in lowland Lesotho, but proprietary equine anthelmintics assist in managing infection. The apparent lack of age-acquired immunity to P. equorum infection may deserve further investigation. Although O. equi infection is less widespread, measures to protect younger animals may be appropriate.

Prevalence of Gastrointestinal Parasites of Horses and Donkeys in and around Gondar Town, Ethiopia

“…Study conducted in Western highlands of Oromia, Ethiopia indicated 2.1% prevalence of Oxyuris equi in horses [11]. Similar study in Lesotho showed slight higher prevalence (6.2%) in horses [28]. The lowest prevalence might be due to the effect of relative higher temperature in the present study area which desiccates the highly susceptible Oxyuris equi egg.…”

“…This result is higher than the prevalence reported in Ethiopia by Yoseph et al [29], Fikru et al [11], Getachew et al [30] who reported 15.7%, 7.3%, and 16.2%, respectively and in Lesotho by Melissa et al [28] who reported 21.6% in horses. The prevalence of Parascaris equorum was 42.29% in donkeys in the present study is higher than 15.7% and 17.3% reported by Yoseph et al [21] and Fikru et al [11] in donkeys.…”

“…The reported prevalence in donkeys from four sites in Ethiopia, 43.5% [31], 50% [23], 51% [32] and 51% [27], slightly agrees with the present study. The difference in prevalence of Parascaris equorum from different reports in developing countries is somewhat conflicting and this could be due to compromised immune responses relating to concurrent disease, but is worthy of further investigation [28].…”

“…Only very few areas, where summer tributaries are dried off are found to be swampy. The work of Getachew et al [27] was in fasciolosis endemic area and is not representative for the whole country [28].…”

Epidemiological Study on Equine Gastrointestinal Helminth Parasites in Mekelle, North Ethiopia

“…This has been mentioned in literatures [26]. Upjohn et al [27] revealed that there seemed to be an inverse association between age and intensity of strongyle infection, i.e., as horses gets older, the odds of higher egg count are reduced.…”