Surubim-do-Paraíba oocytes viability after being exposed to different cryoprotectants
Data
2018-01-01
Autores
Lopes, Taís da Silva
Sanches, Eduardo Antônio [UNESP]
Caneppele, Danilo
Romagosa, Elizabeth
Título da Revista
ISSN da Revista
Título de Volume
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Resumo
To know the non-toxic cryoprotectants to fish oocytes is of extreme importance for tests that aim to increase oocyte resistance to cold, thus allowing more advanced studies in cryopreservation. Therefore, commonly used cryoprotectants such as methanol, dimethyl sulfoxide, ethylene glycol, propylene glycol, sucrose and fructose were studied. Immature oocytes from the initial to vitelogenic (diameter <1.7 mm) and mature (diameter >1.8 mm) stages of Steindachneridion parahybae were evaluated. Four distinct experiments were performed, three using immature oocytes and one using oocytes at the mature stage. For each oocyte stage, the best maintenance solution to be used: Hank or 50% L15 and; viability after baths for 30min (room temperature) at cryoprotectant concentrations ranging from 0.25 to 4M were evaluated. Different tests were used to evaluate oocyte viability: in vitro maturation followed by observation of germinal vesicle breakdown (only for immature oocytes), Trypan Blue staining (all stages) and fertilization and hatching rates (mature stage only). Results showed that the toxic effect of cryoprotectants on oocytes generally increases with increasing concentrations. Sensitivity of oocytes to cryoprotectants increases according to the stage of development, with mature oocytes being more sensitive. Sucrose, fructose, methanol, propylene glycol and dimethyl sulfoxide can be used as cryoprotectants for S. parahybae oocytes.
Descrição
Palavras-chave
Concentrations of cryoprotecntants, Fish oocytes, Fish reproduction, Steindachneridion parahybae, Toxicity
Como citar
Ciencia Rural, v. 48, n. 6, 2018.