Serum free embryo culture medium improves in vitro survival of bovine blastocysts to vitrification.
The aim of this study was to examine the effects of co-culture with Vero cells during the in vitro maturation (IVM) and three culture media, B2+5% fetal calf serum (FCS) on Vero cells, synthetic oviduct fluid (SOF)+5% FCS, and SOF+20 gL(-1) bovine serum albumin (BSA), on the developmental competence of the embryos and their ability to survive vitrification/warming. We also tested the effect of morphological quality and the age of the embryo on its sensitivity to vitrification. The IVM system neither affects the embryo development up to Day 7 nor survival rates after vitrification. The culture of embryos in SOF+FCS and in Vero cells+B2 allowed obtaining more Day 6 and Day 7 blastocysts, and a higher % of Day 7 blastocysts vitrified than culture in SOF+BSA. Contrarily, on Day 8, more blastocysts were vitrified in SOF+BSA than in SOF+FCS. Blastocysts quality affected development after vitrification/warming, and Day 7 embryos showed higher survival rates than their Day 8 counterparts. Day 7 blastocysts produced in Vero cells or in SOF+BSA survived at higher rates than those produced in SOF+FCS at 24 and 48 h after warming. Embryo culture with BSA allows obtaining hatching rates after vitrification/warming higher than those obtained after co-culture with Vero cells in B2 and FCS. Moreover, this system provides hatching rates from Day 8 blastocysts comparable to those obtained on Day 7 in Vero cells. Further studies, including embryo transfer to recipients, are needed to clarify factors affecting the freezability of in vitro produced bovine embryos.
Gómez
E
E
SERIDA, Camino de los Claveles 604, Somió. 33205 Gijón, Spain.
Rodríguez
A
A
Muñoz
M
M
Caamaño
J N
JN
Hidalgo
C O
CO
Morán
E
E
Facal
N
N
Díez
C
C
D000818:Animals; D001755:Blastocyst / Q000502:physiology*; D002417:Cattle / Q000502:physiology*; D002522:Chlorocebus aethiops; D018920:Coculture Techniques / Q000662:veterinary; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary*; D016895:Culture Media, Serum-Free; D046149:Embryo Culture Techniques / Q000662:veterinary*; D004622:Embryo, Mammalian; D047108:Embryonic Development / Q000502:physiology*; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods / Q000662:veterinary*; D008297:Male; D012710:Serum Albumin, Bovine; D014709:Vero Cells
D016895:Culture Media, Serum-Free; D012710:Serum Albumin, Bovine