Large or Food Animal and Equine Medicine Commons^™

Parasite Dynamics In Untreated Horses Through One Calendar Year, Ashley E. Steuer, Haley P. Anderson, Taylor Shepherd, Morgan Clark, Jessica A. Scare, Holli S. Gravatte, Martin K. Nielsen

Veterinary Science Faculty Publications

BACKGROUND: Horses are host to a plethora of parasites. Knowledge of the seasonality of parasite egg shedding and transmission is important for constructing parasite control programs. However, studies describing these patterns are sparse, and have largely been conducted only in the United Kingdom. This study evaluated strongylid egg shedding patterns and transmission dynamics of Strongylus vulgaris in naturally infected and untreated mares and foals through one calendar year in Kentucky, USA. The study also investigated the existence of a peri-parturient rise (PPR) in strongylid egg counts in foaling mares and collected information about Strongyloides westeri and Parascaris spp. in the …

Climate Change Is Likely To Increase The Development Rate Of Anthelmintic Resistance In Equine Cyathostomins In New Zealand, Christian W. Sauermann, Dave M. Leathwick, Mark Lieffering, Martin K. Nielsen

Maxwell H. Gluck Equine Research Center Faculty Publications

Climate change is likely to influence livestock production by increasing the prevalence of diseases, including parasites. The traditional practice of controlling nematodes in livestock by the application of anthelmintics is, however, increasingly compromised by the development of resistance to these drugs in parasite populations. This study used a previously developed simulation model of the entire equine cyathostomin lifecycle to investigate the effect a changing climate would have on the development of anthelmintic resistance. Climate data from six General Circulation Models based on four different Representative Concentration Pathways was available for three New Zealand locations. These projections were used to estimate …

Comparative Analysis Of Intestinal Helminth Infections In Colic And Non-Colic Control Equine Patients, Heidrun Gehlen, Nadine Wulke, Antonia Ertelt, Martin K. Nielsen, Simone Morelli, Donato Traversa, Roswitha Merle, Douglas Wilson, Georg Von Samson-Himmelstjerna

Maxwell H. Gluck Equine Research Center Faculty Publications

All around the world, intestinal helminths constitute one of the most prevalent life-long occurring infections and re-infections affecting all horse age groups. A range of parasite species among strongyles, ascarids, and tapeworms is known to have the potential to cause colic in horses. However, there is a lack of current scientific evidence on the actual relevance of helminth infection levels in the context of colic in horses kept during prevailing epidemiological conditions. Thus, a prospective case-control study on the occurrence of intestinal helminths in a total of 620 mainly adult equine clinic patients was conducted to investigate the association between …

Meta-Analysis Of Cyathostomin Species-Specific Prevalence And Relative Abundance In Domestic Horses From 1975-2020: Emphasis On Geographical Region And Specimen Collection Method, Jennifer L. Bellaw, Martin K. Nielsen

Maxwell H. Gluck Equine Research Center Faculty Publications

BACKGROUND: Cyathostomins infect virtually all horses, and concomitant infections with 10 or more species per horse is standard. Species-specific knowledge is limited, despite potential species bias in development of disease and anthelmintic resistance. This is the first meta-analysis to examine effects of geographical region and cyathostomin collection method on reported composition of cyathostomin communities.

METHODS: Thirty-seven articles published in English in 1975 or later, in which adults of individual species were systematically enumerated, were included. Seven regions; North America, South America, eastern Europe, western Europe, northern Europe, southern Africa, and Oceania, and three cyathostomin collection methods; (i) standard necropsy recovery …

Host-Parasite Interaction In Horses: Mucosal Responses To Naturally Acquired Cyathostomin Infections And Anthelmintic Treatment, Ashley Elaine Steuer

Theses and Dissertations--Veterinary Science

Cyathostomins are ubiquitous parasites in equids. In rare cases, cyathostomins lead to a generalized typhlocolitis and death. In healthy horses, local reactions are noted to the mucosal larvae; however, the mechanisms and importance of these reactions have not been elucidated. It has been hypothesized that anthelmintics can alter these reactions. Currently, three drug classes are approved for use in horses against cyathostomins; while all products target the adults, only two products are labeled as larvicidal. Adulticidal therapy is implicated in triggering the typhlocolitis, however, current evidence is contradictory. There is also conjecture that the larvicidal drugs can increase the risk …