We have an exciting post for you today. Dr. Ernie Martinez has written a piece detailing the steps taken at Lane’s End in preparation for foaling. It’s a great example of how Lane’s End leaves nothing to chance. You can follow Dr. Martinez on twitter at @emartinezdvm.
Alys also sent us some great photos of Zenyatta’s first colt playing in the snow.
Enjoying Late Pregnancy & Preparing for Foaling
By Ernie Martinez II. DVM from Hagyard Equine Medical Institute
As Zenyatta approaches the end of her second pregnancy, we begin to prepare for the arrival of Little 13Z. Very little will change from her daily routine. She will continue to be fed and checked by farm staff twice a day. They will begin to closely monitor her for any signs of premature labor. These might include early udder development or an abnormal vaginal discharge. Thankfully, Queen Z has strided through this pregnancy like a champ and everything has been very routine.
In the last trimester we vaccinate her with a three shot series of vaccinations for Rotaviral diarrhea. This can be a very life threatening diarrhea when acquired in the neonatal stage, and we do all we can try to prevent this disease or at best minimize the severity of any clinical signs. All farm mares receive this series of vaccinations, and we have had very healthy newborn foal crops for some time.
When Queen Z has one month to go we will give her annual series of booster vaccinations. This serves two purposes. First, we provide Queen Z with her annual booster of vaccinations for protection against Equine Herpes Virus 4&1, Eastern-Western Encephalitides, West Nile, Influenza, Rabies & Botulism. Second, and most importantly, by vaccinating her one month before to foaling we will booster the volume and quality of antibodies in her colostrum. Newborn foals are born immunologically naive and must consume and absorb the antibodies from colostrum for their initial immune protection. When 13Z is born we will test her colostrum to insure it is of high quality. If it were to be low, we will give the new foal a pint of colostrum from our colostrum bank. When 13Z is between ten to twelve hours old we will test a blood sample to determine the IgG, or antibody, level. We want all our foals to be above 800 mg/dL. Greater than 1200 mg/dL would be off the charts and even better!
As the foaling date draws nearer, Zenyatta will be brought up to the foaling barn where she will stay until she foals. In the foaling barn she will be under 24 hour surveillance as we patiently wait for her to foal. As she gets closer to foaling, or parturition, her udder will start to develop and the teats will fill. The classic sign that foaling is near is the production of wax or “waxing up.” This is a sebaceous-like pre-colostral secretion that in most cases means foaling is imminent.
Two weeks before Queen Z’s due date we will sample and test her blood for neonatal isoerythrolysis, or NI. We call it an NI Screen. NI occurs when the foal ingests colostrum from the mare with antibodies that react with the foals red blood cells (RBCs). The antibodies are produced by the mare due to transplacental hemorrhage in late gestation. The mare’s immune system identifies the RBCs as foreign because they contain stallion DNA. If the foal were to consume NI antibodies in the colostrum the foal’s RBCs would be coated in the maternal antibodies and cleared by the foal’s immune system, causing a hemolytic anemia. The foal would crash in respiratory distress as it would have no RBCs to carry oxygen. Thankfully, the NI screen allows us to detect NI positive mares. In a positive case we would muzzle the foal and supplement it with tested negative colostrum until the antibodies were cleared from the mares milk. This normally takes 10–12 hours.
So when she draws close to foaling time we will have done all we can do to insure that her colostrum will be top quality, we will have screened her colostrum for NI and we’ve made an easier pathway for the birth of 13Z. Now all we can do is wait.
See you at the Foaling Barn!