Nematodes are parasitic worms that can infect horses, affecting their health and well-being. These parasites typically inhabit the gastrointestinal tract of equines, where they can cause a variety of health issues. Common nematodes affecting horses include strongyles, ascarids, and pinworms. The presence and load of nematodes in horses can lead to symptoms such as weight loss, colic, and diarrhea, and can impact overall performance and health. Monitoring and managing nematode infections is an important aspect of equine veterinary care. This page compiles peer-reviewed research studies and scholarly articles that explore the biology, epidemiology, and management strategies of nematode infections in horses.
Fifteen horses harboring naturally acquired, patent Parascaris equorum and Oxyuris equi infections were equally allotted to 3 treatment groups given (1) injectable vehicle; (2) injectable ivermectin at the dose rate of 200 microgram/kg of body weight; and (3) injectable ivermectin at the rate of 300 microgram/kg. All treatments were given IM in the neck. All animals were killed 14 days after treatment and examined for the targeted nematodes. Regardless of dose rate, ivermectin proved 100% effective in the removal of adult O equi and P equorum infections. Levels of immature P equorum were decre...
Halvarsson P, Grandi G, Hägglund S, Höglund J.A relatively new method to study the species richness and diversity of nematode parasites in grazing animals is to perform deep sequencing on composite samples containing a mixture of parasites. In this work, we compared species composition of strongyles in two groups of horses as a function of egg count and age, based on a DNA barcoding approach. Faecal egg counts and larval cultures were obtained from nearly 300 horses, i.e., domestic horses (n = 167) and trotters (n = 130) sampled nationwide. The second internal transcribed spacer region (ITS2) of strongyle nematodes in the larval cultu...
Abbas G, Bauquier J, Beasley A, Jacobson C, El-Hage C, Wilkes EJA, Carrigan P, Cudmore L, Hurley J, Beveridge I, Nielsen MK, Hughes KJ, Stevenson MA....This study assessed worm control practices used by Australian Thoroughbred farm managers with an online questionnaire survey. The questionnaire comprised 52 questions (close-ended: 44; open-ended: 8) about farm demography and general husbandry practices, farm managers' knowledge of gastrointestinal nematodes (GIN) and their importance, diagnosis, worm control strategies and anthelmintics, anthelmintic resistance (AR) and grazing management. Following the pilot survey, the link for the questionnaire survey was sent to all (n = 657) registered members of the Thoroughbred Breeders Australia on ...
Malsa J, Boudesocque-Delaye L, Wimel L, Auclair-Ronzaud J, Dumont B, Mach N, Reigner F, Guégnard F, Chereau A, Serreau D, Théry-Koné I, Sallé G....Cyathostomins are the most prevalent parasitic nematodes of grazing horses. They are responsible for colic and diarrhea in their hosts. After several decades of exposure to synthetic anthelmintics, they have evolved to become resistant to most compounds. In addition, the drug-associated environmental side-effects question their use in the field. Alternative control strategies, like bioactive forages, are needed to face these challenges. Among these, chicory (Cichorium intybus, Puna II cultivar (cv.)) is known to convey anthelmintic compounds and may control cyathostomins in grazing horses. To ...
Merlin A, Larcher N, Vallé-Casuso JC.This study assessed the anthelmintic resistance in strongylid nematodes against commonly used anthelmintic (AH) drugs in a French galloping racehorse stud farm from March to December 2023. Faecal egg count reduction tests (FECRTs) were conducted in three different groups of Thoroughbred yearlings (a group of 6 males, a group of 13 females and a group of 8 females and 3 males) following the new World Association for the Advancement of Veterinary Parasitology (WAAVP) guidelines. The efficacy of fenbendazole was tested in two groups once during the monitoring period (in March), the efficacy of iv...
Byrne O, Gangotia D, Crowley J, Zintl A, Kiser L, Boxall O, McSweeney D, O'Neill F, Dunne S, Lamb BR, Walshe N, Mulcahy G.Cyathostomins are globally important equine parasites, responsible for both chronic and acute pathogenic effects. The occurrence of mixed infections with numerous cyathostomin species hinders our understanding of parasite epidemiology, host-parasite dynamics, and species pathogenicity. There have been few studies of cyathostomin species occurring in horses in Ireland, where temperate climatic conditions with year-round rainfall provide suitable conditions for infection of grazing animals with bursate nematodes. Here, we amplified and sequenced the ITS-2 region of adult worms harvested at post-...
Ferreira I, Pinto JG, Oliveira EGL, Azevedo MCBS, Marcolino LMC, Ferreira-Strixino J.Habronema muscae is a parasitic nematode that causes habronemiasis in horses, leading to chronic skin lesions. The parasite is transmitted via flies, and larvae deposited in wounds result in difficult-to-heal "summer sores". This case study involved treating a 9-year-old gelding male horse with recurrent habronemiasis using photodynamic therapy (PDT) concurrent with conventional treatments. The horse presented with ulcerated, exudative wounds on its limbs and face, unresponsive to traditional treatments. PDT was applied over six months, using methylene blue (MB) as a photosensitizer, combined ...
