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RESEARCH ARTICLE

Effects of lipid polarisation on survival of in vivo-derived porcine zygotes vitrified by the superfine open pulled-straw method

J. Gomis A , C. Cuello A , J. Sanchez-Osorio A , M. A. Gil A , I. Parrilla A , M. A. Angel A , J. M. Vazquez A , J. Roca A and E. A. Martinez A B
+ Author Affiliations
- Author Affiliations

A Department of Animal Medicine and Surgery, Faculty of Veterinary Medicine, Regional Campus of International Excellence, University of Murcia, E-30071 Murcia, Spain.

B Corresponding author. Email: emilio@um.es

Reproduction, Fertility and Development 25(5) 798-806 https://doi.org/10.1071/RD12179
Submitted: 28 April 2012  Accepted: 3 July 2012   Published: 20 August 2012

Abstract

This study aimed to evaluate the post-warming in vitro viability of intact porcine zygotes vitrified using the superfine open pulled-straw (SOPS) method and to investigate whether cryotolerance is increased by lipid polarisation before vitrification. In vivo-derived zygotes (n = 317) were either untreated before SOPS vitrification or subjected to one of the following pre-treatments: (1) centrifugation (20 min, 15 000g) or (2) equilibration in high-osmolality medium (6 min, 400 mOsm kg–1) followed by centrifugation. Vitrified–warmed and non-vitrified fresh zygotes were cultured in vitro for 120 h. There were no differences in the blastocyst formation rates between the vitrification groups (from 35.4 ± 5.3% to 48.2 ± 5.6%), but fresh zygotes exhibited higher (P < 0.001) blastocyst formation rates (87.5 ± 5.3%) than did vitrified–warmed zygotes. The total blastocyst cell number was similar among all groups (from 34.9 ± 2.8 to 44.1 ± 2.8). In conclusion, SOPS vitrification is a promising method for the cryopreservation of untreated in vivo-derived porcine zygotes. Neither lipid polarisation by centrifugation nor exposure to a high-osmolality medium followed by centrifugation affected the post-warming in vitro viability of zygotes. Our study also demonstrated that the donor is an important factor in determining the success of vitrification for in vivo-derived porcine zygotes.

Additional keywords: centrifugation, cryopreservation, delipidation, pig embryo, vitrification, zygote.


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