03/27/2026
We’re about 2 1/2 weeks away from Penelope’s approximate due date and she is just starting to build a small bag! We know it’s not for everyone, but we like to milk test our mares as another tool to help predict foaling. Hopefully this can help someone else anxiously awaiting their mare to foal!
Here’s how we milk test:
1. Once the mare has built a decent bag, with clean hands we express a small amount of milk (typically one good sq**rt) into a clean container.
2. We will then draw up 1cc of the milk into a small syringe (we prefer a 3cc syringe) and take a picture for reference of how she’s progressing. In such a small amount, milk color and opacity are easier to see in a smaller syringe.
3. The 1cc of milk then gets mixed with 6cc of distilled water in another clean container.
4. Using a pool water test strip (we like the Clorox brand from Walmart or Lowes), we dip it in the diluted milk for a second or two, making sure to get the block wet that tests for pH.
5. Lay the strip on a flat surface for a few seconds for the color to develop.
6. Snap a picture of the test strip to keep as a reference for how the mare is progressing. This also helps to look back on at each subsequent foaling and establish a general pattern for each mare. I have an album on my phone for each mare where I keep progression pictures of bellies, udders, hind ends, and milk tests to refer back to at the next foaling.
7. When the pH measured is high (high 7’s/ low 8’s or bright pink) we know we have some time before the mare should foal. We will typically skip a day, maybe two before testing again. Milk at this stage is typically watery and yellow.
8. As the pH starts to drop (high 6’s to low 7’s or muted orangey/ pink) we will test the mare at the same time every day. Milk will begin to get a bit more cloudy.
9. Once the pH bottoms out (low 6’s or light orange/yellow) and the milk is looking more white and opaque, we know the mare should be very close to foaling, typically within 12 hours.
In the pictures below, we tested Penelope’s milk in the evenings and after the last test each year she had a foal on the ground between 4am and 7am.
This is a tool we use to help predict foaling, but it’s not a guarantee, especially with maiden mares who certainly don’t follow the rules.
Once we begin testing Penelope this year, we will post our photos so that anyone who wants to can follow along and guess when she might foal!
