Embryo recovery rate and recipients' pregnancy rate after nonsurgical embryo transfer in donkeys.
Sixty-three embryos were recovered out of 83 estrous cycles (75.9%) and 98 ovulations (64.3%) of five Pantesca jennies, 2 to 5 yr old, naturally mated or artificially inseminated with fresh semen. Embryo recovery rate was influenced by number of ovulations per cycle (133% and 63% for double and single ovulations, respectively), by the day of embryo recovery attempt (12%, 83%, and 75% at Days 7, 8, and 9 after ovulation, respectively), and by the repetition of the embryo recovery attempt on successive cycles (60%, 79%, and 100% for cycles 1 to 7, 8 to 14, and 15 to 24, respectively). All recovered embryos but three were classified as good or excellent. Of 58 nonsurgical embryo transfers to Ragusana jenny recipients, 13 (22.4%), 10 (17.2%), and 9 (15.5%) resulted in a pregnancy at Days 14, 25, and 50, respectively. Recipients' pregnancy rate was not influenced by the evaluated parameters: embryo quality and age, media employed to wash embryos, days after ovulation of the recipient, experience of the operator. Between 14 and 50 d of pregnancy, 4 of 13 (30.7%) embryos were lost with an influence of the days from ovulation of the recipient: recipients at Days 5 or 6 kept all pregnancies (N=7), whereas recipients at Days 7 or 8 lost 3 of 4 pregnancies, as one of the two recipients at Day 3. More studies are needed before embryo transfer could be considered a reliable tool to preserve endangered donkey breeds.
Camillo
F
F
Dipartimento di Clinica Veterinaria, Università di Pisa, San Piero a Grado (PI), Italy. fcamillo@vet.unipi.it
Panzani
D
D
Scollo
C
C
Rota
A
A
Crisci
A
A
Vannozzi
I
I
Balbo
S
S
D000818:Animals; D001947:Breeding; D003247:Conservation of Natural Resources / Q000379:methods; D004624:Embryo Transfer / Q000379:methods / Q000662:veterinary*; D056727:Endangered Species; D018397:Equidae; D030762:Estrous Cycle; D005260:Female; D005865:Gestational Age; D007315:Insemination, Artificial / Q000662:veterinary; D010060:Ovulation; D011247:Pregnancy; D013997:Time Factors; D020858:Tissue and Organ Harvesting / Q000662:veterinary*