Foal Care
 Mare Nutrition
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An important safeguard during your mare's pregnancy is immunization against Equine Herpesvirus 1 (EHV-1) at the beginning of the 5th, 7th and 9th months of gestation. The EHV-1 strain of Equine Herpesvirus is the leading cause of infectious viral abortions in mares. EHV-1 is typically associated with late-term abortions and the delivery of a well-preserved fetus and outwardly normal placenta. Most horses become infected with EHV-1 during the first year of life. In the majority of cases, the virus becomes latent, just waiting for stress-induced reactivation. Sources of infection for pregnant broodmares include: clinically ill horses shedding the virus in nasal secretions; asymptomatic horses experiencing reactivation of latent infection; or virus laden uterine secretions and placenta/fetus from mares aborting due to EHV-1.

To reduce the risk of EHV-1 abortion, vaccinate your mare with Prodigy® at the start of months 5, 7 and 9 of gestation. All horses in close contact with broodmares - such as barren mares, stallions and teaser stallions - should also be maintained on a rigorous EHV-1 vaccination program. It's also important to reduce your pregnant mare's exposure to groups of young horses and any new arrivals that may be shedding EHV-1. Consult your veterinarian for more information on vaccinating with Prodigy.

Booster vaccinations 4 to 8 weeks before foaling.
You should booster your pregnant mare 4 to 8 weeks prior to foaling. This important series of pre-foaling booster vaccinations stimulates the mare to produce high levels of protective antibodies at a time during late pregnancy when she is also producing antibody-rich colostrum. The newborn foal relies on ingestion of colostrum and absorption of these antibodies during the first 12 to 24 hours of life for protection against a wide variety of viral and bacterial diseases during the early post-natal period.

Booster your mare 4-8 weeks prior to foaliing for:

Vaccination against Strangles, Potomac Horse Fever, Botulism and Rotavirus is recommended only if there is a high risk of disease in your region or on your farm. Consult with your veterinarian to determine if these vaccines are indicated for your mare. In particular, over-vaccination against Strangles can increase the risk of an immune mediated reaction called purpura hemorrhagica that can be debilitating and even fatal. If your mare has recently recovered from Strangles infection, resides in an area with a history of Strangles, or she has received frequent Strangles vaccinations, ask your veterinarian about drawing a blood sample from your mare to measure SeM antibody levels prior to vaccination using the IDEXX Laboratories/EBI Streptococcus equi ELISA Test. The risk of purpura is increased following vaccination of horses with SeM levels above 1,600.

Merck Animal Health’s Influenza Vaccines