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Vertebrate reproductive science and technology
RESEARCH ARTICLE

Comparative effects of adding β-mercaptoethanol or l-ascorbic acid to culture or vitrification–warming media on IVF porcine embryos

Miriam Castillo-Martín A C , Sergi Bonet A , Roser Morató A and Marc Yeste B
+ Author Affiliations
- Author Affiliations

A Biotechnology of Animal and Human Reproduction (TechnoSperm), Department of Biology, Institute of Food and Agricultural Technology, University of Girona, Campus Montilivi, E-17071 Girona, Spain.

B Unit of Animal Reproduction, Department of Animal Medicine and Surgery, Faculty of Veterinary Medicine, Autonomous University of Barcelona, E-08193 Bellaterra, Spain.

C Corresponding author. Email: miriam.castillo@udg.edu

Reproduction, Fertility and Development 26(6) 875-882 https://doi.org/10.1071/RD13116
Submitted: 9 April 2013  Accepted: 5 June 2013   Published: 2 July 2013

Abstract

The aims of the present study were to; (1) determine the effects of supplementation with two antioxidants during in vitro culture (IVC) on embryo development and quality; and (2) test the effects of adding the antioxidants to vitrification–warming media on the cryotolerance of in vitro-produced (IVP) porcine blastocysts. In Experiment 1, presumptive zygotes were cultured without antioxidants, with 50 µM β-mercaptoethanol (β-ME) or with 100 µM l-ascorbic acid (AC). After culture, blastocyst yield, quality and cryotolerance were evaluated in each treatment group. In Experiment 2, survival rates (3 and 24 h), total cell number, apoptosis index and the formation of reactive oxygen species (ROS) in blastocysts vitrified–warmed with 100 µM AC or 50 µM β-ME or without antioxidants added to the vitrification medium were compared. Antioxidant addition during IVC had no effect on embryo development, total cell number or the apoptosis index, and culturing embryos in the presence of β-ME had no effects on cryotolerance. In contrast, ROS levels and survival rates after vitrification–warming were significantly improved in embryos cultured with AC. Furthermore, addition of AC into vitrification–warming media enhanced embryo survival and embryo quality after warming. In conclusion, our results suggest that supplementing culture or vitrification media with 100 µM AC improves the quality and cryosurvival of IVP porcine blastocysts.

Additional keywords: antioxidants, apoptosis, blastocysts, cryotolerance, reactive oxygen species.


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