Effect of polyvinyl alcohol or fetal calf serum and warming temperature on post-¬thawing survival rate and in vitro maturation of vetrified buffalo oocytes [electronic resource].

Includes references.

The present study was designed to study the influence of two levels (2 and 4 mg/ml) of Polyvinyl alcohol (PVA), 20%fetal calf serum (FCS) and no additive in vitrification solution (VS) as well as two thawing temperature degrees (20 and 250C) on in vitro maturation of buffalo oocytes. Oocytes were recovered from ovarian follicles with diameter of 3-7 mm by aspiration from ovaries collected from slaughterhouse. Oocytes enclosed in a compact cumulus cells with evenly granulated cytoplasm were selected. Results show that post-thawing survival rate (SR) of all oocytes increased (P<O.05), to 77.4 and 79.6% with two levels of PVA (2 and 4 mg/ml of VS), respectively, and to 87.1% with 20% FCS vs. 62.4%for VS with no additives. The post-thawing survival rate of normal oocytes showed the same trend, being 54.0,59 and 68.8% vs.35.4%, respectively. The effect of post-thawing warming temperature on survival rates was not significant, although these rates tended to be higher with 25 than 20"C. Maturation rate in term of percentage of oocytes at M II¬ stage was higher (P<O.05) for fresh than vitrified oocytes (67.6 vs. 21.2-34.0%). The percentage of oocytes at M Il-stage was 34%for oocytes vitrified with VS and FCS. 26.3% and 28.7% with 2 and 4 mg/ml PVA, respectively, and 21.2% with VS with no additive (P<0.05). In conclusion supplementing VS with PVA (2 or 4 mg) or FCS (20%) improves maturation rate of vitrified buffalo oocytes.

Summary in Arabic.

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