Written by Dr Alex Leander BVSc MPhil, Equine Reproductive Veterinarian at Waikato Equine Veterinary Centre and committee member NZ Thoroughbred Breeders’ Association Waikato Branch and Foster Foal Services.

The Foster Foal Service is run by the NZTBA Waikato Branch for our Thoroughbred Breeders that are members of our association. Of the kindness of our hearts we also help breeders that are not members, but this service is running thin, due to many private persons using our service and not paying the fee.

We are forever grateful to the studs and private people that offer their mare as a Foster mare at a time of great sadness and loss of a precious foal. Any birth carries a risk to both the mum and the baby, and this is true for all species. Did you know that in 2022 (latest published figures) the percentage of births in women in New Zealand that were done by c-section was 32%! That will be due to a mix of dystocia due to fetal size but in humans we also have the option for elective c-sections. In equine breeding our rate of c-sections are not that high, but we have still performed a number this season at the clinic. The rate of dystocia in mares is reported to be in the range of 2-13% of all equine births, and 4% in Thoroughbreds (Vandeplassche 1993).

Every equine dystocia is an emergency and requires clinical skill and quick decisions from the stud staff and vets. We strongly recommend to foal all mares at a specialist foaling down place or at a studfarm that have 24/7 watch of the mares and have the experience to deliver foals safely. Do not foal at home if you don’t know what you are doing , you are risking both the mare and the foals’ lives.

The best fosterings happen in the first days after foaling. If the mare lost her foal at birth she will often stand by the foal (despite no signs of it being alive), for several days. If we can match her with an orphan during this time it often works straight away. So keep the foal with the mare! Taking it away too early causes stress and severe grievance in the mare and will make the fostering process harder. Also keep the placenta in a bucket as the smell of placental membranes and fluids can be used as an aid in the fostering process. Be quick in your decision if you are prepared to let your mare go for fostering, the sooner the better after losing her own foal. And it will be beneficial for the mare also to have a baby to care for.

A recently foaled mare will have suitable milk for an orphaned foal. A mare produce colostrum for the first 12-24hours post partum), and then the composition changes to normal milk. Please milk the colostrum off the mare and freeze in 200-400ml aliquots, this is liquid gold and could help give immunity to another foal down the line. Milking her also stimulates the production of more milk and will prepare the mare for successfully rearing a foal. Mares dry up very quickly 1-3days if the udder is not stimulated. Hence why we might decline a mare if it’s too long ago she lost her foal.

If we have a suitable orphan and the mare has been put up for fostering we can easily “trick” her that the orphan is actually her own foal. We might use the fetal membranes and fluids on the orphan to make it smell “more familiar” and we can use some medications to help let the milk down (oxytocin) and or some sedation to make the mare calm and receptive to the new baby drinking. We also use oxytocin and prostaglandin together, which makes the mare a little sweaty and cause uterine contractions, which simulates the birth has just happened and there you go, “here is an orphan with my membranes on it” so it tricks the mare into thinking it’s her own newborn foal.

Again we might decline a mare that has lost a foal that’s 4months old or a mare that has just weaned her foal at 8months. There is very little chance that we can trick that mare, she knows very well that this is not her foal and most mares will be aggressive towards the orphan and doesn’t matter what we do will not accept it. There is the odd exception to this where a very kind mare may just take any foal. But please do not be offended when we decline offers of newly weaned mares, it just doesn’t work! Waste of time in 99% of cases. We are better off waiting a day or 2 for a freshly foaled mare. And as you understand we have to keep our orphans safe and staff also doing the fostering process.

Location is another issue often encountered. No stud will send their very valuable foal to a private persons bush block in another region. If you are prepared to let the mare travel great but don’t assume a foal will be delivered to your place, it just isn’t commercially viable to do so for the studs. Travelling mares and foals long distances is not practical in most cases we try to match in close locations.

Hope this explains a little more what we do and why we may or may not accept some mares. We work hard during the season to help foals find a Foster Mum so help us where you can.

If you would like more information, please call or email us.