Population structure of Haemonchus contortus from seven geographical regions in China, determined on the basis of microsatellite markers

Background: Studying genetic variation within and among Haemonchus contortus populations can inform some aspects of this parasite's population genetics and epidemiology. However, almost nothing is known about such variation in China. Methods: Adult males of H. contortus (n = 184) representing seven distinct populations in China were collected, and genetic variation within and among these populations was explored using eight distinct microsatellite markers. Results: Genetic parameters, such as heterozygosity and inbreeding coefficient (F-IS) indicated that all eight microsatellites were highly polymorphic. Various analyses (AMOVA, F-ST, phylogenetic, structure, mantel test and population dynamics) revealed high within-population variation, low population genetic differentiation and high gene flow for H. contortus in China. Conclusions: This study provides a first snapshot of the genetic substructuring of H. contortus populations in China using polymorphic markers, and might provide a starting point for assessing genetic changes over space and time during or following the implementation of particular treatment or control strategies, or changes as a consequence of environmental, management and climatic factors.