Superovulation, in vivo Embryo Recovery and Cryopreservation for Aoudad (Ammotragus Lervia) Females Using Osmotic Pumps and Vitrification: A Preliminary Experience and its Implications for Conservation

Abstract

The aoudad (Ammotragus lervia) is a wild ruminant considered the living ancestor of domestic sheep and goats. The original distribution of aoudads includes several countries in the North of Africa, but it has been introduced, for trophy-hunting purposes, into other countries (USA, Mexico and Spain).The species was declared vulnerable in the 2012 IUCN's Red List and is also included in the CITES II Appendix. Surprisingly, little is known about its conservation status or the reproductive biology of the natural populations. There are some reports of the application of basic assisted-reproduction techniques in captive aoudads. In this preliminary study, we explored the feasibility of implementing assisted reproduction procedures in captive aoudad females using non-traditional techniques for in vivo embryo production. This approach was used to obtain the best results using the minimum possible number of animals. Three aoudad females were synchronized using a domestic sheep protocol and subcutaneous osmotic pumps for the delivery of follicle-stimulating hormone. A mini-surgical approach combined with laparoscopy was performed to obtain in vivo-produced embryos. All females had an ovulatory response of more than three corporea lutea, but only five good quality morulae were obtained from one female. Those were cryopreserved by vitrification using a Cryotop®. In conclusion, our approach was successful in obtaining in vivo embryos using a limited number of females. Further studies are necessary to optimize the fertilization rate and clarify the effect of our protocol on embryo implantation and the production of offspring.Keywords: Aoudad; Cryotop®; osmotic pumps; superovulation; vitrification, wild ruminant. ResumenAmmotragus lervia, aoudad, es un rumiante silvestre considerando el ancestro de los borregos y cabras domésticas. La distribución original de los aoudad incluye varios países en el Norte de África, pero ha sido introducido, con propósitos de cacería en otros países (EUA, México y España). La especie se declara como vulnerable en la Red List 2012 de la IUCN y también se incluye en el Apéndice II del CITES. Sorprendemente, poco se sabe del estado de conservación o de la biología reproductiva de las poblaciones naturales. Existen algunos reportes de la aplicación de técnicas básicas de reproducción asistida en hembras de aoudad captivas. En este estudio preliminar, exploramos la factibilidad de implementar procedimientos de reproducción asistida en hembras de aoudad captivas usando técnicas no tradicionales para la producción de embriones in vivo. Este enfoque fue utilizado para obtener los mejores resultados utilizando el menor número posible de animales. Tres hembras de aoudad fueron sincronizadas usando un protocolo de borregas domésticas y bombas subcutáneas para la administración de la hormona folículo estimulante. Un abordaje mini-quirúrgico combinado con laparoscopia fue realizado para obtener los embriones producidos in vivo. Todas las hembras tuvieron una respuesta ovulatoria de más de tres cuerp...

Response to FSH (Folltropin-V) and hCG treatment on superovulation and embryo production in sheep under sub-tropical climate

“…Forcada et al (2012) [18] observed 50-60% recovery rate while Ramon-Ugalde et al (2008) [47] observed 70% recovery rate after uterus flusing in superovulated ewes. Very low recovery rate was observed by López-Saucedo et al (2013) [35] in wild Barbery sheep of Mexico. Since pedigree records of born lambs were maintained in the breeding farm where this experiment was performed, single male was used for breeding which may be a cause of low fertilization and low embryo recovery rate in our experiments, this may be improved in future by use of two males or intra uterine insemination (López-Saucedo et al, 2013) [35] , which require further standardization.…”

“…Very low recovery rate was observed by López-Saucedo et al (2013) [35] in wild Barbery sheep of Mexico. Since pedigree records of born lambs were maintained in the breeding farm where this experiment was performed, single male was used for breeding which may be a cause of low fertilization and low embryo recovery rate in our experiments, this may be improved in future by use of two males or intra uterine insemination (López-Saucedo et al, 2013) [35] , which require further standardization. According to Leoni et al (2001) [31] , the recovery rates could be reduced by the ovarian hypertrophy which might have obstructed the fimbriae to capture the oocytes after ovulation.…”

<b>Gamete cryopreservation in the recovery program of Mexican gray wolf</b> (<i>Canis lupus baylei</i>):<b> Results of reproductive season of 2018 in Mexico</b>

“…This will create the resources and develop species-specific expertise within the mexican community and facilitate the annual breeding plans without the need of move animals or disrupt social structures of packs already established at facilities. The research and results detailed in this report are the product of a longstanding collaboration between our Institute and several mexican zoos for the purpose of reproductive assessment and cryopreservation of gametes and embryos (López-Saucedo et al 2013;Piña-Aguilar et al, 2016). Such collaborations enable animal conservationists access to advanced assisted reproduction techniques and have proven effective for other international groups as well (Comizzoli et al, 2018;Silber et al, 2013).…”