title: Cycle and duration of the seminiferous epithelium in puma (Puma concolor).
abstract: Puma or sussuarana (Puma concolor) is the second largest feline in the American continent and has an ample latitudinal distribution in very diverse habitats. In relation to its conservation status, the puma is considered an extinction-threatened species. The study of the testis morphology and the spermatogenic process in a species is fundamental for establishing the physiologic patterns that will make possible the selection of the protocols for assisted reproduction. A number of peculiarities associated with the reproductive biology of specific species such as the duration of spermatogenic process can be used to determine the frequency of sperm collection. Nine adult male pumas maintained in captivity were used to determine the relative frequency of stages in the seminiferous epithelium cycle. Three of them received intra-testicular injections of 0.1ml tritiated thymidine to determine the duration of the seminiferous epithelium cycle, and were subjected to biopsy 7 days later. The cycle of the seminiferous epithelium in puma was didactically described into eight stages by the tubular morphology method. The total duration of one seminiferous epithelium cycle in puma was calculated to be 9.89 days, and approximately 44.5 days are required for development of spermatozoon from spermatogonia. The duration of spermiogenesis, prophase and other events of meiosis were 14.08, 15.20 and 1.79 days, respectively. The relative frequency of the pre-meiotic, meiotic and post-meiotic phases were 3.98, 1.79 and 4.12 days, respectively.
authors.affiliation: Veterinary Department, Federal University of Viçosa, Minas Gerais 36571-000, Brazil.
authors.forename: Flaviana Lima Guião
authors.initials: FL
authors.lastname: Leite
authors.forename: Tarcízio Antônio Rego
authors.initials: TA
authors.lastname: de Paula
authors.forename: Sérgio Luis Pinto
authors.initials: SL
authors.lastname: da Matta
authors.forename: Cláudio Cesar
authors.initials: CC
authors.lastname: Fonseca
authors.forename: Marco Túlio David
authors.initials: MT
authors.lastname: das Neves
authors.forename: João Bosco Gonçalves
authors.initials: JB
authors.lastname: de Barros
mesh_terms: D000818:Animals; D002466:Cell Nucleolus / Q000648:ultrastructure; D002467:Cell Nucleus / Q000648:ultrastructure; D008297:Male; D008540:Meiosis; D046011:Puma; D012670:Seminiferous Epithelium / Q000502:physiology / Q000648:ultrastructure*; D012708:Sertoli Cells / Q000648:ultrastructure; D013087:Spermatids / Q000648:ultrastructure; D013090:Spermatocytes / Q000648:ultrastructure; D013093:Spermatogonia / Q000648:ultrastructure; D013997:Time Factors