Haylo! Thanks for dropping by for the next “Mare” chapter of our Repro edition blog! Last week we discussed confirmation of pregnancy, management of twins, and the ‘last ditch’ 25-30 day check. Now we are going to discuss the remainder of pregnancy and birth. There are many facets and approaches to pregnancy management – we are going to discuss what the Springhill doctors view is of ideal management.
Starting at breeding, you should be managing your mare in a variety of ways. She should be in a clean, comfortable space with companions who are not a source of stress. She should have ample access to plenty of high quality hay and clean water. Changing over to a higher protein (14%) grain is recommended (although Senior feed is always best for older mares), but please refer to my segment where I visited Dr. Lacher’s feed room! A mare’s demands change as the baby grows, as she can physically fit less fibrous feedstuffs, and has to rely more on concentrated grains.
We recommend starting pregnant mare vaccines at 3 months of pregnancy – particularly Pneumobort (Rhinopneumonitis). This vaccine is repeated at month 5, 7 and 9 of pregnancy. It helps to prevent abortions caused by specific strains of equine herpes virus (Rhinopneumonitis). Your mare should also receive her EWT vaccine every six months (starting prior to breeding), and should be boostered 4-6 weeks prior to foaling. Your mare should be vaccinated for Rabies and West Nile prior to breeding, and then again with the EWT vaccine 4-6 weeks prior to foaling. These vaccines will help boost her antibody levels just prior to producing the colostrum (first milk) that will supply the foal’s immune system for the first 4-6 months of life.
She should be checked regularly for any pus or other discharge from her vulva, which is sometimes seen underneath and/or in the tail. Discharge during pregnancy often indicates placentitis, an infection of the placenta that compromises the foal and the pregnancy. You should be monitoring your mare’s udder in late pregnancy for signs of development. Early development (5-9 months) can indicate placentitis as well. Please call if your mare exhibits these signs, so we can get your mare on antibiotics (often they use the free ones from Publix!)! If your mare does abort, please let us know and the vets can try to decipher the reason (eg, it could be one of two twins!)!
Ultrasounds can also give us information about the placenta and the foal. Dr. Lacher and Dr. King can attempt to determine if it is a boy or a girl between 59 and 65 days. We use ultrasound later in pregnancy (5-11 months) to determine the state of the placenta, the fluids surrounding the fetus, look for signs of infection (placentitis) – of which there are different forms and causes, and measure the heart rate of the baby. For example, we can measure the thickness of the placenta just in front of the cervix to see if it is thickened. This often indicates bacteria are ‘climbing in’ through a leaky valve – the cervix. This commonly occurs in mares that have had past foaling difficulty and damage to their cervix. If the foal’s heart rate is elevated, it indicates stress (like with placentitis), and if it is slowing down it may indicate impending death.
You should be monitoring your mare’s udder in late pregnancy for signs of development. First the udder begins to fill, but until the teats begin to fill and elongate the mare likely still has time. The first secretions will be a thin, watery drip, and over days to weeks it will change to a thick, sticky white milk. You can bring samples of milk to the clinic in a tube or cup (we can provide you) for us to test the relative concentrations of calcium and other ions, which gives us an idea of time until foaling. The closer she gets, the softer the muscles around her tailhead and the longer her vulva will appear. Remember that maiden mares can be much more unpredictable when it comes to pre-foaling development. When the incredible process finally begins, be ready for a few common issues.
A red bag is caused when placentitis makes the “bag” so thick the foal cannot break through. Once the umbilicus breaks, the foal has no source of oxygen. If a red velvety bag is protruding from your mare (Careful! The foal’s feet are behind it!), cut it with a knife ASAP! DON’T WAIT for us to get there! Call us as soon as you have cut the bag and have the foal’s nostrils clear of materials. Another birthing problem is dystocia (difficult birth), which occurs when the foal is malpostitioned, or sometimes with deformities. If your mare is actively foaling (following the water breaking) for more than 30 minutes, you should be calling us! DON’T try to pull a seemingly stuck foal yourself. If only one leg (with or without a nose), two feet but no nose, or feet whose soles face the sky are present, the foal is probably malpositioned. It is crucial to stay calm, and stand by for assistance. Keep the foal’s nose clear if it is visible.
If everything goes as quickly and smoothly as usual, the first thing to know after your mare gives birth is the 1-2-3 Rule. Your foal should stand within one hour of birth, and nurse within two hours. Within three hours of birth, your mare should pass the placenta—keep it (in a garbage bag and/or bucket)! If not, or it appears in any way incomplete, treatment for retained placenta should be started within six hours of birth. We should come see the foal in the first 12-24 hours after birth to do a physical exam (to check for congenital abnormalities, fractured ribs, signs of infection, etc.), and measure the IgG level (an antibody that tells us if the foal received adequate immunity from his mother’s colostrum).
Dr. King and Dr. Lacher absolutely love foals and are happy to discuss any questions you may have regarding management of your mare! Please let them know if you have any questions! If you find yourself still feeling nervous and unprepared for your mare to foal out at the end of this article, consider the Springhill Foaling Package. Thanks for stopping by! May your litter box always be clean, and your food bowl full!