Vitrificação de folículos ovarianos pré-antrais de fêmeas bovinas com dimetilsulfóxido e sacarose acrescida de α-tocoferol

• Ano de defesa: 2010
• Autor(a) principal: Jimenez, Carolina Rodriguez
• Orientador(a): Torres, Ciro Alexandre Alves
• Banca de defesa: Guimarães, José Domingos , Mâncio, Antonio Bento
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Zootecnia
• Departamento: Genética e Melhoramento de Animais Domésticos; Nutrição e Alimentação Animal; Pastagens e Forragicul
• País: BR
• Palavras-chave em Português: Folículos; Ovários; Criopreservação; Vacas
• Palavras-chave em Inglês: Follicles; Ovaries; Cryopreservation; cows
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA::REPRODUCAO ANIMAL
• Link de acesso: http://locus.ufv.br/handle/123456789/5681

The objective of the study was to vitrify the ovarian pré-antral follicles (PF) of cows with dimethylsulfoxide (DMSO) and sucrose (SAC) plus α-tocopherol (TOC), by evaluation of the morphology of PF in situ and viability of post-vitrification isolated PF The study was conducted in the Laboratory of Animal scíence, University Federal of Viçosa. Ovaries were collected from slaughtered cows, with indefined breed and age at different stages of the estrous cycle. Qualitative variables related to viability and morphology of the PF were analised by non parametric test Kruskal-wallis and chi-square, respectively, at 5% probability. In the first experiment 66 ovaries of bovine females were used, fragments were cut with 5 mm3 approximately. Fragments were randomly assigned to nine treatments, represented by control (fixed in fresh) and four vitrification solutions (VS) with two thawing types each, represented as follows: SV1m: DMSO, with thawing in minimum essential medium (MEM); SV1s:DMSO, with thawing in SAC; SV2m: DMSO + SAC, with thawing in MEM; SV2s: DMSO + SAC, with thawing in SAC; SV3m: DMSO + SAC + TOC 5 mM, with thawing in MEM; SV3s: DMSO + SAC + TOC 5 mM, with thawing in SAC; SV4m: DMSO + SAC + TOC 10 mM, with thawing in MEM; SV4s: DMSO + SAC + TOC 10 Mm, with thawing in SAC. Each cut, after thawing, was fixed for classical histology and stained with hematoxylin and eosin and observed under 400x optical microscope. Thirteen thousand and five hundred (13,500) PF were analyzed, 6,238 primordial, 6,812 primary and 450 secondary, which were classified as good, regular and bad. It was concluded that DMSO, SAC and TOC may be used in the cryopreservation of bovine females PF. It is recommended to work with DMSO, SAC and 10 TOC mM thawed in MEM and DMSO and SAC thawed in MEM or SAC for PF cryopreservation. The second experiment 51 ovaries of cows were used, been cut, treated, cryopreserved and thawed as described in the first experiment. After thawing, the fragments were mechanically dissociated using maintenance M199 medium and 5% bovine serum albumin in order to, filtrate and subsequently isolates the PF.The viability of PF was examined with trypan blue, dead and alive stained or unstained respectively, and observed under inverted microscope with increase 400X. Fiftteen hundred (1,500) isolated PF were analyzed per treatment, with a total of 13,500 observed. The Results showed that the control, ie, PF without vitrification, differed from all of cryopreserved treatments, thus showing that cryopreservation affect the viability of isolated PF. However, the treatments of vitrification with DMSO, SAC and TOC 10 mM, irrespective of the thawing procedure, showed the best results of viability after cryopreservation.