Factors Affecting Embryo Recovery Rate, Quality, and Diameter in Andalusian Donkey Jennies

Area of Science:

• Animal Reproduction and Genetics
• Conservation Biology
• Embryology

Background:

• Embryo transfer and vitrification offer potential for conserving endangered donkey breeds.
• Optimizing recovery rates and cryotolerance of donkey embryos is crucial for conservation success.

Purpose of the Study:

• To evaluate factors influencing embryo recovery, quality, and diameter in Andalusian donkeys.
• To establish a baseline for improving vitrification and embryo transfer techniques for donkey conservation.

Main Methods:

• Collected and analyzed 100 embryos from 124 estrous cycles in donor jennies.
• Assessed embryo recovery rates, quality, and diameter.
• Statistically analyzed the impact of donor factors, flushing parameters, and herd differences.

Main Results:

• Overall embryo recovery rate was 80.6%.
• Donor jenny, donor age, number of flushings, day of flushing, successive cycles, and jack significantly affected recovery, quality, and developmental stage.
• Specific factors like donor jenny, number of flushings, and day of flushing influenced key metrics.

Conclusions:

• Donor jenny, age, successive cycles, flushing day, number of flushings, and jack are critical factors for successful embryo transfer and vitrification.
• Identifying these factors is essential for enhancing the efficiency of assisted reproductive techniques in endangered donkey conservation.