title: Genetic analysis of inbreeding of two strains of the parasitic nematode Haemonchus contortus.
abstract: Haemonchus contortus is a sheep parasitic nematode that causes severe economic losses. Previous studies have indicated a high degree of genetic heterogeneity, which is hardly affected by selection for drug resistance. As a tool for the analysis of the population dynamics of H. contortus and its response to drug resistance, we designed a strategy to study the inbreeding of a benzimidazole-sensitive and a benzimidazole-resistant strain. After 15 generations, a theoretical inbreeding coefficient of 0.87 was achieved. The different stages of inbreeding were analysed using restriction fragment polymorphism, microsatellite variability and amplified fragment length polymorphism. Model-based clustering of the amplified fragment length polymorphism genotypes showed that the allele frequencies of the benzimidazole-resistant strain were stable during the last eight generations. In the sensitive strain a gradual shift of allele frequencies was observed, which led to a temporary increase of the genetic diversity around the eight generations.
authors.affiliation: Department of Molecular Recognition, Institute for Animal Science and Health (ID-Lelystad), Lelystad, The Netherlands. m.h.roos@planet.nl
authors.forename: Marleen H
authors.initials: MH
authors.lastname: Roos
authors.forename: Myrthe
authors.initials: M
authors.lastname: Otsen
authors.forename: Ruurdtje
authors.initials: R
authors.lastname: Hoekstra
authors.forename: Jetty G
authors.initials: JG
authors.lastname: Veenstra
authors.forename: Johannes A
authors.initials: JA
authors.lastname: Lenstra
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents; D001562:Benzimidazoles; D004352:Drug Resistance, Microbial / Q000235:genetics; D017238:Genes, Helminth; D014644:Genetic Variation; D006189:Haemonchus / Q000235:genetics / Q000502:physiology*; D007178:Inbreeding; D012756:Sheep; D012757:Sheep Diseases / Q000469:parasitology*; D013045:Species Specificity
chemical_list: D000900:Anti-Bacterial Agents; D001562:Benzimidazoles; C031000:benzimidazole