Ultrastructural evaluation of cryopreserved caprine sperm through transmission electronic microscopy
Keywords:
Animal reproduction, Eletronic microscopy, Goat, Small ruminantsAbstract
The ultrastructure evaluation allows the analysis of the sperm cell in a subcellular proportion that is not observed in optical microscopy. Transmission electron microscopy (MET) is a tool used to determine the size and shape of inorganic and biological structures based on the interaction of electrons incident on matter. In this sense, with the use of MET, the objective was to evaluate the ultrastructural changes after the semen manipulation, mainly in the freeze-thaw process, which were not observed in tests using optical microscopy, that is, the morphological integrity of the membranes and goat sperm organelles. The evaluation took place at the Institute of Biosciences of the University of Brasília (UnB). The semen straws were thawed and washed in PBS. Then, they were centrifuged and fixed, contrasted in bloc and subjected to dehydration. The samples were placed for polymerization and ultrathin cuts were made and stored until the time of MET evaluation. In the ultrastructural analyzes by MET in the present work, no harmful actions occurred in either the control or experimental groups. The head regions (plasma membrane and acrosome) remained preserved, with no change in DNA. In conclusion, MET is especially useful tool for cell evaluation.
References
BURGESS, C.M.; BREDL, J.C.S.; PLUMMER, J.M.; INGLATERRA, G.C. Vital and ultrastructural changes in dog spermatozoa during cryopreservation. Journal of Reproduction and Fertility, v.57, supl.1, p.357-363, 2001.
ENCISO, M.; CISALE, H.; JOHNSTON, S.D.; SARASA, J.; FERNANDEZ, J.L.; GOSÁLVEZ, J. Major morphological sperm abnormalities in the bull are related to sperm DNA damage. Theriogenology, v.76, n.1, p.23-32, 2011.
FRANCO, J.G.Jr.; MAURI, A.L.; PETERSEN, C.G.; MASSARO, F.C.; SILVA, L.F.I.; FELIPE, V.; CAVAGNA, M.; PONTES, A.; BARUFFI, R.L.R.; OLIVEIRA, J.B.A.; VAGNINI, L.D. Large nuclear vacuoles are indicative of abnormal chromatin packaging in human spermatozoa. International Journal of Andrology, v.35, n.1, p.46-51, 2011.
LAVOLPE, M.; LORENZI, D.; GRECO, E.; NODAR, F.; SEDÓ, C. A. Relationship Between Sperm DNA Fragmentation and Nuclear Vacuoles. JBRA Assisted Reproduction, v.19, n.2, p.70-74, 2015.
MOURA, C.S.; NUNES, A.K.S.; SILVA, B.S.; PEIXOTO, C.A.; SILVA, A.R.; SILVA, S.V.; GERRA, M.M.P. Efeito da temperatura de descongelação na integridade de espermatozoides criopreservados de cães. Arquivo Brasileiro de Medicina Veterinária e Zootecnia, v.65, n.4, p.1057-1064, 2013.
SILVA, E.C.B. Efeito da adição de diferentes crioprotetores e antioxidantes na criopreservação do sêmen de ovinos da raça Santa Inês. 2010. 95p. (Dissertação de Mestrado em Medicina Veterinária). Universidade Federal Rural de Pernambuco, Recife, 2010.
SILVA, M.A.; PEIXOTO, G.C.X.; CASTELO, T.S.; LIMA, G.L.; SILV, A.M.; OLIVEIRA, M.F.; SILVA, A.R. Cryopreservation of collared peccary (Pecari tajacu) semen using different freezing curves, straw sizes, and thawing rates. Cryobiology, v.67, n.1, p.50-55, 2013.
SILVA, R.A.C.; SOUZA, T.O.; DIAS, L.P.; ANDRADE, T.J.A.S. Ação do extrato metanólico da Moringa oleifera sobre o crescimento micelial de fitopatógenos. In: Congresso de Pesquisa e Inovação da Rede Norte e Nordeste de Inovação Tecnológica, 4., 2009, Belém-PA. Anais... Belém: Congresso de Pesquisa e Inovação da Rede Norte e Nordeste de Inovação Tecnológica, 2009.
SOARES, A.T.; SILVA, S.V.; ALMEIDA, F.C.; LEMOS, P.F.B.A.; NUNES, J.F.; PEIXOTO, C.A. Espermatozoides caprinos criopreservados em meio à base de leite desnatado acrescido de glutationa reduzida. Ciência Rural, v.41, n.11, p.1991-1997, 2011.
