Page 60 - NM Winter 2023

COMMON EQUINE NEONATAL ILLNESSES
by Megan Petty, DVM
Foaling season is a game of minutes. Sometimes it’s the 5 minutes you step away in the middle of the night for a cup of coffee that the mare decides to foal. Sometimes it’s the minutes during parturition that make the difference between life and death. The minutes between determining
that a neonate is sick and initiating treatment
can also make all the difference in prognosis. The following is certainly not an exhaustive list, but covers some of the more common, life-threatening ailments affecting the equine neonate.
FAILURE OF PASSIVE TRANSFER (FPT)
Probably the most commonly encountered condition of the newborn foal, failure of passive transfer, thankfully, is also one of the most easily diagnosed. Foals who suffer from failure of passive transfer are more likely to die from sepsis
and contract secondary issues such as “joint ill” (septic arthritis). The equine neonate derives 100% of its immune system from the colostrum, or “first milk”, consumed in the first hours of life. To improve colostrum quality, it is common practice to vaccinate the mare 4-6 weeks prior to her due date, which is when the antibody rich colostrum is being created and concentrated in the udder of the mare. Failure of passive transfer occurs if the foal fails to consume the necessary colostrum or if the mare fails to produce (or loses) colostrum of adequate quality.
Diagnosis of failure of passive transfer
can be made as soon as 6 hours after the foal has consumed its first meal by testing for Immunoglobulin G (IgG). The magic number that makes the heart of any equine veterinarian or farm manager soar is 800mg/dl and likewise, the number that strikes fear and dread on the
58 New Mexico Horse Breeder
tIgG SNAP test with a result of over 800. © Megan Petty