Transplantation of Tissue from Native and Cryopreserved Pekin Duck Ovaries to Mulard Ducks with Study of Hormonal Changes After Grafting

Orthotopic transplantation of ovarian tissue at one day of age is a promising solution for preserving female genetic material in avian species; using sterile recipients can ensure that all offspring are donor-derived. This study focuses on the suitability of the Mulard duck as a sterile recipient for Pekin duck donors and provides an investigation of the hormonal background. Firstly, native Pekin ovarian tissue was grafted into Mulard duck recipients, resulting in a 40% adhesion rate and follicular development in 50% of the adhered grafts. Secondly, the transplantation of cryopreserved ovarian tissue resulted in a 66% adhesion rate, with 33% of the adhered grafts showing follicular development. Ovulation occurred in 16% of the recipients with adhered grafts, but the eggs did not move into the oviduct. Estrogen levels were elevated in the recipients with adherence but were lower than in the control Pekin group, while progesterone levels remained unchanged. Consequently, recipients received buserelin acetate, a GnRH analogue, to stimulate follicular and oviductal activity. In this group, graft adhesion occurred in 31% of animals, and primordial follicle development in 25%. The hormonal levels of the recipients with adhered ovaries were elevated, but the GnRH analogue treatment did not affect the ovulation process. We conclude that while the Mulard duck shows potential as a sterile recipient in ovarian transplantation, several questions remain unanswered regarding the adequacy of follicular maturation and ovulation.