Effect of α-tocopherol supplementation on in vitro maturation of sheep oocytes and in vitro development of preimplantation sheep embryos to the blastocyst stage.
OBJECTIVE
To determine the effects of α-tocopherol supplementation to oocyte maturation media and embryo culture media on the yield of ovine embryos.


METHODS
α-tocopherol, at concentrations of 0, 50, 100, 200, 400 and 500 µM was supplemented to ovine oocyte or embryo culture media and cultured at 5% or 20% O(2) levels. Percentages of cleavage, morula and blastocyst, total cell count and comet assay were taken as indicators of developmental competence of embryos.


RESULTS
200 µM α-tocopherol in embryo culture medium at 20% O(2) level significantly increased the rates of cleavage (P < 0.05), morulae (P < 0.05) and blastocyst (P < 0.01) formation and blastocyst total cell number (P < 0.01) when compared with control. The rates of blastocyst formation were also significantly higher in 100 µM (P < 0.01) and 400 µM (P < 0.05) supplemented groups than control.


CONCLUSIONS
α-tocopherol supplementation may enhance the in vitro developmental competence of ovine embryos by protecting them from oxidative damage.
Natarajan
Rajesh
R
Department of Industrial Biotechnology, Dr MGR Educational and Research Institute - Dr MGR University, Maduravoyal, Chennai 600095, Tamilnadu, India. r_jesh2002@yahoo.com
Shankar
Madhira Bhawani
MB
Munuswamy
Deecaraman
D
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001755:Blastocyst / Q000166:cytology / Q000187:drug effects*; D003470:Culture Media; D046149:Embryo Culture Techniques; D047108:Embryonic Development / Q000187:drug effects*; D005260:Female; D005307:Fertilization in Vitro; D009865:Oocytes / Q000187:drug effects*; D018384:Oxidative Stress; D012756:Sheep / Q000196:embryology*; D024502:alpha-Tocopherol / Q000494:pharmacology*
D000975:Antioxidants; D003470:Culture Media; D024502:alpha-Tocopherol
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