Etossulfato de fenazina na maturação in vitro de oócitos bovinos

• Autor(a) principal: Correia, Pâmella Alves
• Data de Publicação: 2019
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFLA
• Texto Completo: http://repositorio.ufla.br/jspui/handle/1/36833
• topic: Phenazine ethosulfate (PES); Maturação in vitro; Embriões bovinos; Vitrificação; Aquecimento; Bovine embryos; Vitrification; Heating; Zootecnia

The objective was to evaluate different doses of phenazine ethosulfate (PES) during in vitro maturation of bovine oocytes and their consequences until thawing in vitrified embryos. The concentrations 0; 0.16; 0.4 and 1.0 µM were evaluated on embryo production, hatching and expansion rates, lipid content and morphological characteristics. Refrigerator oocytes (n = 2,232) were matured for 24 hours, part was subjected to fluorescence analysis, the others were cultured to D7, of which the grade I embryos were vitrified, then heated and cultured for 48 hours. A minimum of 550 CCOs per treatment were matured in 13 replicates resulting in 400 vitrified embryos. Data were analyzed by SAS® statistical package. The rate of embryos produced for the Control (C = 41.5 ± 1.8, n = 237) was higher (P <0.01) compared to PES0.16 (32.5 ± 1.7, n = 182). ) and PES1 (32.6 ± 1.7, n = 186), but did not differ from PES0.4 (35.6 ± 1.7% n = 210). The treated groups did not differ from each other. The hatching rate (P = 0.10) tended to be higher for PES1 (34.3 ± 5.6, n = 32) and PES0.4 (32.4 ± 5.6, n = 38) in Control (27.2 ± 5.7, n = 13) and PES0.16 (22.4 ± 5.8, n = 17). The expansion rate after 48 hours of cultivation was the same (P <0.05) for the Control (27.1 ± 5.2, n = 20), PES0.16 (24.3 ± 5.6, n = 20) and PES1 (10.3 ± 2.0, n = 12). The groups PES0,4 (17,7 ± 3,5, n = 10) and PES1 did not differ from each other. Higher proportion of PES1 oocytes (P <0.01) reached advanced meiosis stages (> 90%) than Control (50%). There was no treatment effect on the amount of apoptotic cells or MCI. In D9 there was an increase in apoptotic cells (P <0.01) and a reduction in the number of total cells (P <0.01) and MCI (P <0.01) in blastocysts. Lipid concentration (triglycerides, phospholipids and cholesterol) in oocytes was lower (P <0.01) in treated groups compared to Control. PES1 and PES0.4 triglycerides did not differ from Control during cultivation; in PES0.16 were higher (P = 0.01) than Control. The phospholipid and cholesterol concentrations of PES0.4 and PES0.16 were higher (P <0.01) than in Control and PES1. Blastocysts that survived and hatched 48 hours after thawing were 77% of PES0.4, 72% of PES1, versus 44% of PES0.16 and 25% of Control indicating a positive treatment effect. Lipid concentration was decreased by PES in oocytes, but apparently there was a compensatory effect in the culture phase, so PES used only during IVM may lead to lipid increase in embryos.