Optimization of quantitative techniques for enumerating mucosal stages of Cyathostomin nematodes in the horse

Abstract

In researching equine parasites, larval cyathostomin populations must be quantified. Mechanical digestion was developed over 30 years ago to enumerate encysted stages of cyathostomes. This study examined the optimal digestion times for liberating early stage L3 larvae (EL3) and late stage L3 and L4 larvae (collectively known as DL). Mucosal samples from both the cecum and large intestine were digested for 60, 90, 120 or 150 min. A time effect (p = 0.032) was observed for EL3 in the cecum, with the greatest number at 150 min. The ventral colon showed a similar time effect (p = 0.035) being greatest at 150 min. There was no effect on DL from 60-150 min in either the cecum (p = 0.71) or ventral colon (p = 0.67). Longer time intervals should be examined to determine the optimum time for liberating EL3, while a different test for DL is recommended.