Mitochondrial function, blastocyst development and live foals born after ICSI of immature vitrified/warmed equine oocytes matured with or without melatonin

Oocyte vitrification is considered experimental in the horse with only three live foals reported. The oxidative conditions induced by could part explain poor results and melatonin, a powerful antioxidant, stimulate ROS metabolization restore mitochondrial function these oocytes. Our objective was to determine status of vitrified equine oocytes analyze effect melatonin on mitochondrial-specific (mROS), oocyte maturation, ICSI embryo development viability. Immature, abattoir-derived were held for 15 h final concentration 20% EG, DMSO 0.65 M trehalose. In Experiment 1, overall determined DCHF-DA; increased production compared non-vitrified controls (1.29 ± 0.22 vs 0.74 0.25 a. u.; P = 0.0156). 2, mROS analyzed MitoSOX™ vitrified/warmed matured (+) or without (?) supplementation 10?9 melatonin; decreased presence (P < 0.05). 3, we assessed after ICSI, viability pregnancy establishment. Melatonin did not improve cleavage blastocyst rate However, reached similar (61, 75 77%, respectively) (15, 29 26%, than non-vitrified, Vitrified, had lower (46%) (9%) groups 0.05), but no significant differences observed when (+). Although lack available recipients precluded transfer every produced our study, transferred embryos from resulted 50 83% rates while 17 33% rates, treatments respectively. Two healthy foals, one colt filly treatment, born Gestation lengths (considering day 0 ICSI) 338 days 329 filly, work showed first time that horse, as other species, intracellular reactive oxygen species are process vitrification. useful reducing mitochondrial-related improving development, although should be further future studies. To knowledge this report an vitro culture system its use developmental competence following ICSI.