Postmortem examination (2016-2017) of weanling and older horses for the presence of select species of endoparasites: Gasterophilus spp., Anoplocephala spp. and Strongylus spp. in specific anatomical sites.

This study focuses on assessing the prevalence of specific parasite species in horses after death, using a sample collected from the University of Kentucky Veterinary Diagnostic Laboratory. According to the study, Gasterophilus intestinalis, Gasterophilus nasalis, and Anoplocephala perfoliata were found in a significant number of horses, while two species of Strongylus were not detected at all.

Background and Methodology

• The study was conducted because detecting parasites is easier after an animal’s death.
• A sample of dead weanling and older horses submitted to the University of Kentucky Veterinary Diagnostic Laboratory (UKVDL) for examination between November 2016 and March 2017 was selected for the study.
• Specific anatomical sites of the horses, including the stomach, duodenum, cecum, and part of the ileum, were thoroughly examined for the presence of three specific groups of parasites.

Findings

• Among the 69 horses whose stomach and duodenum were examined for Gasterophilus spp. parasites (commonly known as bots), 19% were infected with Gasterophilus intestinalis, and the prevalence of Gasterophilus nasalis was 1.5%.
• The research noted movement in a few third instar G. intestinalis preserved in 10% formalin even over 200 hours later.
• The cecum and parts of the ileum of 139 horses were examined for tapeworms (Anoplocephala spp.) and large strongyles (Strongylus spp.). 44% of these were found to be infected with Anoplocephala perfoliata.
• Neither Strongylus vulgaris nor Strongylus edentatus was detected in any horse examined during the research.

Conclusion

• The study concludes that a significant number of horse deaths could be related to infestations of Gasterophilus intestinalis, Gasterophilus nasalis, and Anoplocephala perfoliata.
• The absence of Strongylus vulgaris and Strongylus edentatus in the examined horses was also a key finding, indicating that these species were not responsible for the death of these horses.