Seasonal variations cause morphological changes and altered spermatogenesis in the testes of viscacha (Lagostomus maximus)

Autor(es)

Godoy Pieri, Naira Caroline ^[1] ; da Silva Santos, Paulo Ramos ^[1] ; Santos Roballo, Kelly Cristine ^[1] ; Flamini, Mirta Alicia ^[2] ; Barbeito, Claudio Gustavo ^[2] ; Ambrosio, Carlos Eduardo ^{[1, 3]} ; Miglino, Maria Angelica ^[1] ; Martins, Daniele dos Santos ^[3]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Fac Vet Med & Anim Sci, Dept Surg, Sao Paulo - Brazil

^[2] Natl Univ La Plata, Sch Vet Sci, La Plata, Buenos Aires - Argentina

^[3] Univ Sao Paulo, Fac Anim Sci & Food Engn, Dept Vet Med, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Animal Reproduction Science; v. 149, n. 3-4, p. 316-324, OCT 2014.
• Citações Web of Science: 5

Resumo

This study complements the previous investigations of the reproductive biology of male viscachas, a rodent of a seasonal Hystricognathi that exhibits photoperiod-induced morphological variations in the reproductive system. In the present study, a quantitative analysis of spermatogenesis was performed during the summer and the spring. Spermatogonial cells were analyzed to determine by immunolabelling for STRA8 and DAZL, which are essential for spermatogenesis. Six free-living male viscachas were captured, three animals in the summer during the period of reproductive activity and three animals in the spring during the period of testicular regression. The testes of the viscachas were collected and processed for light microscopy, macroscopic and immunochemical analyses. The germ and Sertoli cells present in the seminiferous tubules were quantitatively analyzed in each animal. The efficiency coefficient for spermatogonial mitosis, meiotic yield, overall spermatogenesis yield and Sertoli cell index, revealed that the Sertoli cells in male viscachas captured during the summer had a reduced capacity to structurally and nutritionally support the developing round spermatids compared with the male viscachas captured during the spring. The animals produced less sperm during the spring than the summer, suggesting a seasonal impact on spermatogenesis. Immunolabelling for STRA8 and DAZL was detected during summer and spring seasons. These results suggest that in seasonal rodents, such as the male viscachas, the photoperiod promotes significant changes in the testis and in the germ cell yield. (C) 2014 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 10/10683-0 - Biologia da reprodução da Viscacha (Lagostomus maximus): uma parceria entre Brasil e Argentina para integração da biotecnologia da reprodução em animais ameaçados
• Beneficiário: Daniele dos Santos Martins
• Modalidade de apoio: Auxílio à Pesquisa - Regular