Mexican veterinarian Filix in action
To breed foals from approved Friesian Studbook stallions breeders in foreign countries often have to resort to frozen semen from the Netherlands. There are various factors that determine whether or not frozen semen results in a successful impregnation. Frozen semen loses its fertility in the mare after twelve hours. Egg cells must be fertilised within eight hours after ovulation. The chances of insemination are highest when the semen is injected into the mare as closely as possible to the moment of ovulation. For the success of using frozen semen (as well as embryo transfer), a veterinarian with expertise and experience regarding the supervision of Friesian mares is definitely important.
AI with frozen semen and ET
In September 2018 equine veterinarian Erik Leusink made his first visit to Mexico where he spent a fortnight for the veterinary supervision of Friesian broodmares. He says: ‘The stud in question has purchased about twelve good-quality Friesian broodmares. These mares are also used as donor mares for the embryo transfer programme they have set up together with their own Mexican veterinarian. Along with the Friesian mares they have also bought about fifty surrogate mares so there will always be a mare whose cycle closely matches a donor mare´s. When the results of working with frozen semen as well as flushing embryos proved to be disappointing, they contacted me and asked if I would be willing to share the experience with frozen semen and embryo transfer in Friesian mares which I had built up here in the Netherlands .’
Pregnancy percentages
Leusink continues: ‘The analysis of results and talks with my Mexican colleague Filix soon brought two things to the surface: with fresh semen from their own stallions they achieved high pregnancy percentages as well as successful embryo transfers, but with frozen semen they didn´t. Filix was good and had sufficient skills to supervise and flush the mares but with frozen semen he wasn´t so successful. It emerged that he lived at the other side of Mexico-City and had to travel up and down to the stud every day. All the equipment needed for flushing embryos is available and he also has the necessary hormones to synchronise donor- and surrogate mares to time the moment of ovulation.’
Are you keen to find out more about Veterinarian Erik Leusink´s advice to turn the use of frozen semen and embryo transfer in Friesian mares in Mexico into a success? Then read his full real-life story in the March issue of Phryso.
Veterinarian Erik Leusink is co-founder of 4Horses, an all-round equestrian enterprise in Drachten. Before that he was employed as an equine veterinarian for the Animal Clinic Wolvega for over twenty years. He has specialised in equine reproduction, especially problem mares, insemination of frozen semen and embryo transfer as well as semen examination of stallions. Additionally, he is a Certified Inspection Veterinarian for Horses.