Bisection of equine embryos

Animal Reproduction Laboratory, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado 80523, USA
Equine Veterinary Journal (Impact Factor: 2.37). 06/2010; 21(S8):129 - 133. DOI: 10.1111/j.2042-3306.1989.tb04697.x

ABSTRACT Three experiments were designed to evaluate methods of bisecting equine embryos. Viability of demi-embryos was compared to whole embryos in vitro and in vivo. In Experiment 1, Day 6 embryos were bisected either using a standard micromanipulation technique or a manual split of embryos that were adhered to a petri dish. Viability was assessed by culture in vitro. Bisected embryos in both groups increased in size during culture and developed normally. In general, manual bisection was accomplished with less difficulty and time than the micromanipulation method. Eleven additional embryos were bisected manually and both halves transferred surgically into the same recipient (Experiment 2). More pregnancies were obtained from transfer of twin whole embryos (16/22) compared to bisected, demi-embryos (5/22). In Experiment 3, 30 embryos were bisected manually; 15 were encapsulated in agar chip. Both halves were transferred non-surgically to each recipient. Fifteen whole embryos were transferred non-surgically to recipients as controls. The number of vesicles per original embryo was greater for whole embryos than for demi-embryos in agar chips.

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