Milking It!!

Mares are notoriously fickle creatures. After carefully managing, feeding, and monitoring them throughout their pregnancies, they seem to strive to catch us out at foaling time. Although most births proceed normally and easily, if something does go wrong, it often goes wrong very quickly, and can result in danger to mare, foal, or both. For this reason, it’s strongly advisable to be present for the foaling; however, few small studs and hobby breeders can afford the staffing to stay awake all night to monitor their mares from 320 days onwards. Want to stack the deck in your favour? There are many signs of impending foaling which can help you choose the nights you stay awake: our focus here will be on milk testing.

What is Milk Testing?

If you have looked at your mare’s milk prior to foaling, you have probably noticed progressive changes in colour and texture: progressing from clear and sticky, to cloudy and watery, and finally to opaque, white and sticky. In the days leading up to foaling, calcium content increases sharply as the colostrum begins to build in preparation for the foal’s arrival. There is also a measurable decrease in pH. I’ve never been brave enough, but some very dedicated mare-watchers will have a taste - if it tastes salty, it’s likely that nothing is going to happen. A change from salty to sweet (in combination with other signs) means foaling is imminent!

Milk testing involves checking and recording these features of the milk, and watching for changes. When monitoring Beth last year, I started a chart at 330 days of gestation to track udder size, visual/texture assessment of the milk, calcium content, and pH. I checked these daily at 5pm until I saw some significant progress, and then twice daily, at 8am and 5pm. Because the majority of mares foal at night, most will show dramatic changes on evening checks first.

What Do I Need?

A small container to milk into - a plastic film canister would work wellA second small container with a lid for mixingDistilled water5 ml syringeWater hardness & pH testing strips - check to be sure they are in date.ORCommercial Testing Kit (e.g., CHEMetrics FoalWatch), which will contain all that you need to start testing - including instructions!

A note of caution: All supplies which come into contact with the sample must be cleaned and rinsed with distilled water after each use. Do not use tap water, as calcium found therein can interfere with your results!

Choosing a Test

The test you choose to use will depend on the precision you want from the results. The CHEMetrics FoalWatch kit is very precise, and allows you to track small changes very closely. It’s simple to use after one or two practice runs, and comes pre-packaged with everything you will need. It only contains twenty tests, however, and does not check the pH. Water hardness testing strips of the pool/hot tub variety are comparatively cheap, can be purchased with a pH test on the same strip, and will still give you good results, but these results are displayed as a much wider range, as opposed to the more precise value the CHEMetrics titration kit will give you.

Where Do I Start?

The most logical place to begin, though perhaps not the easiest, is obtaining the milk. Be sure to stand in a safe position adjacent to your mare’s back legs, just behind her flank, and facing the same direction she is, and maintaining contact with the hind leg. Standing farther forward and leaning under her while milking will put your head in a very dangerous position, should she cow-kick in objection to what you are doing. If you have spent time getting your mare accustomed to having her udder handled, this should be a fairly simple exercise. Some cotton wool soaked in warm water did the trick when Beth was feeling particularly itchy and sore. Wash your hands thoroughly, and make sure the teats are gently cleaned and dried before you milk 2-3 ml’s into a small clean container. Dirty hands on a dirty udder can introduce mastitis-causing micro-organisms! Do a quick visual assessment. If the milk is starting to look cloudy, your mare is making progress. If it is opaque and feels tacky, get ready to camp out for the night!

Mission Accomplished. What Now?

If you are science-phobic, take a deep breath. What you are about to do may fall under the heading of Chemistry, but it is not difficult. If you are a science geek, feel free to put on a lab coat and tell your mare to stand back, because you are about to conduct a complicated test. She won’t know the difference. Regardless of whether you are using the test strips or a commercial test, the milk must be diluted in distilled water at a ratio of 6:1. Use your 5 ml syringe to measure 1 ml of milk, and transfer it to the second container. Next, add in 6 ml of distilled water, and mix together by capping and gently shaking the container. If you have more milk available, dilute 1.5 ml in 9 ml of distilled water. If you’re struggling to get even 1 ml out of your mare, mix 0.5 ml in 3 ml of distilled water.

Finally, follow the instructions for checking pH and water hardness, which should be found on the outside of the pot containing the strips. You may have to wait several seconds for the colour change to be complete. Alternatively, if you are using a commercial testing kit, follow the instructions packaged with the kit for drawing up your mixture and getting your result. The calcium (or hardness) reading should be in the hundreds or below. Both methods involve watching for a colour change, and finding that change on a scale to determine calcium concentration.

When Do I Start Sitting Up?

First, a disclaimer! Please take these results in conjunction with other signs of impending foaling, and remember that it this is only intended to help you to be more accurate in determining when your mare will foal. These tests are neither a guarantee that you won’t miss a foaling, nor are they a guarantee that you won’t miss more than one night’s sleep. If your mare is a maiden, watch her like a hawk, as maiden mares are more likely to proceed without much warning. Any sudden, dramatic changes in hardness or calcium readings may also warrant closer observation; for example, the mare who progresses from 50ppm to 175ppm in 24 hours may very well continue on up the scale that same night.

Calcium/Hardness readings

Less than 100 ppm: Get some rest, you’re not there yet.100-175 ppm: Start getting vigilant, and seriously consider testing in the morning as well as evenings.200 ppm: You’ve hit the magic number! Nearly all mares will foal within 72 hours of first hitting this mark, with most foaling within 48 hours. Get the champagne ready.300+ ppm: Foaling is imminent, and likely to occur today. Many mares will not have achieved this high a reading prior to foaling, so bring a book and keep your eyes open!

pH readings

Above 7: You don’t have colostrum yet, try again tomorrow.Below 7: You have colostrum, and your mare will foal within the next day or two!Below 6.8: Your mare will likely foal tonight.

These readings are applicable for most mares. Being a contrary sort, Beth managed to string us along last year for several days. I began testing at 330 days, however she did not exceed 100ppm until day 349. She hit 225ppm on day 350, 300+ppm with a pH of 6 on day 353, and did not foal until the night of day 354. It was obvious that no matter how quiet the person on foal watch was, she knew someone was there. It was a trick she had pulled with her previous foal, waiting until her owner made a quick trip to the house for a bite to eat. Out of desperation, after three days of obvious readiness for foaling, we departed noisily, locking the gate, and driving away. I parked a little way up the road, and snuck back onto the yard through the back gate, taking up my station at the CCTV monitor, and she went into labour a couple of hours later. She was immediately forgiven for her tardiness when she produced another big grey colt, but we are all hoping fervently that she hasn’t passed her tricks on to the three mares which we have due to foal this year…