What you see. The starting point for addressing any equine health related issue is your observation.


Pregnant or Lactating Mare's Udder Seems Small


Udder development should start at about 6 weeks prior to the expected due date. The udder should slowly enlarge up until foaling, with an increase to melon size in the last 1-2 weeks before foaling.

Mares often "come into their milk" within 24 hours of foaling. Generally, foals drink 20% of their body weight in milk per day. Do not rely on the size of the mare's udder as an indication of her milking ability. Many mares with their first foal will have a relatively small udder but may produce adequate milk.

  • Code Red

    Call Your Vet Immediately, Even Outside Business Hours
    • For a routine post-partum examination of foal, mare and placentae.
    • Questions coming up around foaling should usually be discussed right away with your vet.
    • If you feel that the newborn foal is not getting adequate milk.
    • If the young foal appears to be nursing constantly.
  • Code Green

    Contact Your Vet to Obtain Useful Advice & Resources
    • If you are confident that your foal is healthy and thriving other than this sign.

your role


What To Do

You can strip some milk into your hand, but keep in mind that in a relatively short period of nursing a foal can empty one side of the udder, giving you the impression that there is little milk.

Unless there is obviously no milk, let the foal be your guide. If a foal appears dehydrated or is working on the mare's udder constantly, there may be a problem.

If you have any concerns or questions, call your vet to discuss them. A critical question is whether or not the foal received adequate colostrum (first milk) from the mare. An antibody test performed by your vet on the foal's blood can answer that important question.

your vet's role

One way your vet can assess how much milk the mare is producing is by carefully evaluating and monitoring the foal. If the foal seems to be suckling constantly, yet not gaining weight normally, or appears dehydrated, it might be an indicator the mare is not producing enough milk. If your vet determines that this is a problem, there are hormone treatments that can make a significant difference. In other cases, supplementation may be needed.
Questions Your Vet Might Ask:
  • How strong does the foal seem to you?
  • What is the foal doing now?
  • How frequently is the foal nursing?
  • What is the mare's body condition and feeding now?
  • Does the mare have a history of eating fescue hay or being on fescue pasture?
  • Has the mare had prior foals or is she a maiden?

Treatments Your Vet May Recommend

A way to resolve the condition or diagnosis. Resolving the underlying cause or treating the signs of disease (symptomatic treatment)

Very Common
more treatments

further reading & resources

Author: Doug Thal DVM Dipl. ABVP