title: In vivo effect of sublethal concentrations of albendazole metabolites on the structure of the reproductive organs of Dictyocaulus viviparus.
abstract: Dictyocaulus viviparus were harvested from calves treated daily with albendazole at dose-rates sub-lethal to this parasite and from matched untreated calves. Male and female reproductive tracts from the worms were examined by light and transmission electron microscopy. A first description of the testis of this nematode is provided. Cell division in the germinal zone of both male and female worms was arrested by in vivo exposure to albendazole metabolites and the cytoplasmic threads connecting the germinal cells to the rachis disappeared. In male worms from treated calves, the rachis was absent from the growth zone and severe ultrastructural damage of spermatogonia, spermatocytes and spermatozoa was apparent. In female worms, the rachis remained intact in the growth zone, obvious abnormalities being confined to the germinal zone, where the cytoplasm of the oogonia was disrupted and few nuclei seen, and to the uteri and ovijector which contained only undifferentiated ova. The detrimental effects of albendazole metabolites on male and female worms were quickly reversed after withdrawal of medication.
authors.affiliation: Department of Pathology and Infectious Diseases, Royal Veterinary College (University of London), Hatfield, Herts, UK.
authors.forename: A M
authors.initials: AM
authors.lastname: Osman
authors.forename: D E
authors.initials: DE
authors.lastname: Jacobs
authors.forename: J M
authors.initials: JM
authors.lastname: Plummer
mesh_terms: D015766:Albendazole / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000188:drug therapy*; D002455:Cell Division / Q000187:drug effects; D004021:Dictyocaulus / Q000187:drug effects* / Q000648:ultrastructure; D004022:Dictyocaulus Infections / Q000188:drug therapy*; D005260:Female; D005836:Genitalia, Female / Q000187:drug effects / Q000648:ultrastructure; D008297:Male; D008854:Microscopy, Electron; D013737:Testis / Q000187:drug effects / Q000648:ultrastructure
chemical_list: D015766:Albendazole