title: Spermatogenesis is seasonal in the large hairy armadillo, Chaetophractus villosus (Dasypodidae, Xenarthra, Mammalia).
abstract: Very little is known about the distinct reproductive biology of armadillos. Very few studies have investigated armadillo spermatogenesis, with data available only for Euphractus sexcinctus and Dasypus novemcinctus. In the present study, we analysed male germ cell differentiation in the large hairy armadillo Chaetophractus villosus throughout the year, describing a cycle of the seminiferous epithelium made of eight different stages. Evaluation of the testis/body mass ratio, analysis of the architecture of the seminiferous epithelium and the frequency of defective seminiferous tubules allowed identification of a temporal interruption of spermatogenesis during the period between mid-May to July (mid-end autumn) in correlation with very low testosterone levels. Overall, these results suggest that spermatogenesis is seasonal in C. villosus.
authors.affiliation: Laboratorio de Biología Cromosómica, Facultad de Medicina, UBA, Paraguay 2155 10°P Lab 6, Buenos Aires, Argentina.
authors.forename: Juan P
authors.initials: JP
authors.lastname: Luaces
authors.forename: Luis F
authors.initials: LF
authors.lastname: Rossi
authors.forename: Valeria
authors.initials: V
authors.lastname: Merico
authors.forename: Maurizio
authors.initials: M
authors.lastname: Zuccotti
authors.forename: Carlo A
authors.initials: CA
authors.lastname: Redi
authors.forename: Alberto J
authors.initials: AJ
authors.lastname: Solari
authors.forename: Maria S
authors.initials: MS
authors.lastname: Merani
authors.forename: Silvia
authors.initials: S
authors.lastname: Garagna
mesh_terms: D000818:Animals; D001118:Argentina; D001135:Armadillos / Q000502:physiology*; D053144:Cell Nucleus Shape; D042002:Chromatin Assembly and Disassembly; D008297:Male; D046529:Microscopy, Electron, Transmission; D008870:Microtubules / Q000378:metabolism; D009929:Organ Size; D012621:Seasons; D012670:Seminiferous Epithelium / Q000166:cytology* / Q000254:growth & development / Q000378:metabolism / Q000648:ultrastructure; D012708:Sertoli Cells / Q000166:cytology / Q000378:metabolism / Q000648:ultrastructure; D013087:Spermatids / Q000166:cytology / Q000254:growth & development / Q000378:metabolism / Q000648:ultrastructure; D013090:Spermatocytes / Q000166:cytology / Q000254:growth & development / Q000378:metabolism / Q000648:ultrastructure; D013091:Spermatogenesis; D013093:Spermatogonia / Q000166:cytology / Q000254:growth & development / Q000378:metabolism / Q000648:ultrastructure; D013737:Testis / Q000166:cytology / Q000254:growth & development / Q000378:metabolism / Q000648:ultrastructure; D013739:Testosterone / Q000097:blood / Q000378:metabolism
chemical_list: D013739:Testosterone