SUMMARY RESEARCH REPORT: BRITISH VETERINARY ASSOCIATION Comparative observations on strongyle parasites in domestic horses (Equus ferus caballus), Grevy’s zebra (Equus grevyi) and Plains zebra (Equus quagga boehmi) in Kenya – a pilot study

Grevy’s zebra (Equus grevyi) populations declined dramatically in the last decades of the 20 century. Though now stabilising, there has been an estimated 50-68% drop in numbers over the past 18 years (IUCN, 2012). While there are many threats facing the species, the role of parasite burdens in this decline is poorly understood. Lewa Wildlife Conservancy provides ex situ or marginal (transition zone to common zebra dominated habitats) habitat for a small but critical population of Grevy’s zebra which, in one area, shares pasture with a small herd of horses used largely for tourist safaris. The most significant gastrointestinal equid parasites, the strongyles, are recognised as having low host specificity and this study sought to conduct a preliminary investigation into whether this pattern of co-grazing affects the parasite burdens of Grevy’s zebra, horses and plains zebra who also share the pasture. Faecal egg counts were used to estimate parasite burdens, assessed using the widely accepted modified McMasters method.