Evaluation of foal production following intracytoplasmic sperm injection and blastocyst culture of oocytes from ovaries collected immediately before euthanasia or after death of mares under field conditions (original) (raw)

2012, Journal of the American Veterinary Medical Association

T he current success of ICSI and in vitro embryo production 1,2 leads to the possibility of use of these techniques to produce embryos and foals from oocytes collected from valuable mares after death. Much research on in vitro equine embryo production has been conducted with oocytes recovered from mares after death in slaughterhouses 1,3-5 ; however, work with clinical patients involves additional factors, including the cause of death or reasons for euthanasia, duration of illness, medications received, method of euthanasia, conditions of ovary transport, and interval between death of the mare and receipt of ovaries by the laboratory. One report 6 is available, which incorporates data from an earlier report, 7 on production of foals from Evaluation of foal production following intracytoplasmic sperm injection and blastocyst culture of oocytes from ovaries collected immediately before euthanasia or after death of mares under field conditions Katrin Hinrichs, dvm, phd, dact; Young-Ho Choi, dvm, phd; Jody D. Norris, bs; Linda B. Love, ms; Sylvia J. Bedford-Guaus, dvm, phd, dact; David L. Hartman, dvm; Isabel C. Velez, dvm, ms Objective-To evaluate the efficiency of foal production following intracytoplasmic sperm injection (ICSI) and blastocyst culture of oocytes from mares that died or were euthanized under field conditions. Design-Prospective case series. Animals-16 mares (age, 3 to 19 years) that died or were euthanized for various causes. Procedures-Ovaries were collected immediately before euthanasia (n = 10) or after death (6). Ovaries were transported to the laboratory for oocyte recovery (15 mares), or oocytes were recovered at a remote location and shipped to the laboratory (1). Oocytes underwent ICSI, and presumptive zygotes were cultured for 7 to 10 days. Blastocysts were shipped to embryo transfer facilities for transcervical transfer to recipient mares. Results-Ovaries were processed 30 minutes to 12 hours (mean ± SD, 4.6 ± 3.3 hours) after mares' deaths. A mean of 14.1 ± 8.6 oocytes/mare were cultured, and 110 of 225 (49%) matured. Twenty-one blastocysts developed after ICSI and were transferred to recipient mares. Thirteen pregnancies were established; 10 healthy foals were produced from 6 donor mares. The number of blastocysts produced per mare and number of live foals produced per mare were significantly correlated with the number of oocytes recovered. Conclusions and Clinical Relevance-Foals were produced from mares after death or euthanasia under field conditions. Proportions of foals born overall (10 foals/16 mares) and mares from which ≥ 1 foal was produced (6/16) were greater than those reported following recovery and oviductal transfer of oocytes to inseminated recipients after death of donor mares under field conditions.