1. Udder Changes
We like to use udder development as a good indicator of how far along a cow is. This measure is usually effective for dairy cattle, whereas beef cattle do not always “make up” an udder much before calving.
Keep in mind a few things:
- Every cow develops differently. The heifer in these first pictures did not make up as much edema as heifers often do, so she is a good average between heifer and cow.
- Cows that have calved before are very different from heifers. You may not see much change in the udder until a few days before to a day after calving.
A note on the photos below. The Jan 1 photo is after little man (her baby) nursed. He was born in the night and when we peeked out the window about 7am, he was curled up sleeping, dry and full. So that is a post-milking photo. 🙂
2. Pins & Ligaments
Many people may ask about “the pins”. First, you need to know what they are! Pins are a part of a cow’s hips. Basically, “hooks” are the FRONT (closer to head of animal) part of the hips and “pins” are the BACK (closer to tail) part of hips.
Okay, so now, why are “pins” important? Well, 12-24 hours before a cow calves, the pins will change in preparation for calving so that a cow can push a 50-100 pound calf out.
There will be a noticeable loosening of the ligaments on each side – BETWEEN the PIN bone and the TAIL bone, the ligaments will soften and become loose and jelly-like (compared to normal muscle tone/normal ligament strength).
Think of there being a rubber band holding the pin bone to the tail bone, on each side. Picture the rubber band tight. Then picture the rubber band relaxing and sagging, so that when the calf comes out that little tiny space, the rubber band can be stretched wide open (and the pin bones along with it) for the calf to come out.
Seeing this change is a good indication your cow is imminently close to calving – like, time to bring her into the barn and check on her every hour or two!
To Measure Pin Ligament Changes: Do not measure a cow by looking at her once. Rather, start to monitor how she looks and then keep tracking change as she gets closer to her calving date. You may see slight softening of the ligaments as she “blooms” in preparation the final month. But the change we’re talking about is the significant change (up to inches in loosening of the ligaments) that indicate imminent calving.
Thin Cow Disclaimer: Pins are NOT a good reference point on thin cows. If a cow is really thin, she may always look like her ligaments are loose, when it’s really a lack of fat/muscle/bloom.
Same photo, with red circles emphasizing area in question:
Do I find pins a good indicator for beginners to know when their cow is soon to calve? Not necessarily. I find that so many cows are different, I mean recently I saw a cow that looked like Rosalind post-calving (Jan 1 photo) and she waited several more days to calve! Instead, I like to include “pin development” on my list of things to watch (check out the full list on the Calving Preparation page).
This last calving was my first time photographing and marking development of the pins. The photos are more difficult to take versus seeing the cow live, but they can give you an idea of how even on Dec 29, she had not developed a huge amount in the pins. That look was where she had been for almost two months, and I attribute it to the fact that she was a tad on the thin side when she arrived early November to our home.
Another udder example:
March of 2015 calving – First photos taken of heifer about 1 month from calving:
Next photos taken 3 days before due date:
Photos taken night of due date:
Photos at birth (about 7 hours later):
A third example:
Five weeks before due date:
Three weeks before due date:
One week before due date – she’s not gonna make it any longer!
Heifer calf born unassisted about 10:30 pm (earlier photos (above) were taken around 4:30 PM)
Example of a mature dairy cow:
A happy ending … heifer calves! 😀
A few parting notes:
- Heifers tend to calve early, but any cow or heifer can calve several days in one direction or another of her due date. I’ve seen calves born two weeks early or over two weeks late with guaranteed breeding dates (meaning not just that a bull got them on a different heat).
- Be sure you have the right calving date! It’s easy enough to get dates mixed up. Keep records and check a gestation calendar to double check your math. You can find one on this page: Breeding Your Cow
- The “Medicine Box” area of this website has many sections relevant to calving, particularly: Calving Preparation and Medicine Box
- Focus on what is important for this calving. For example, if you have a heifer, you may want to read up on and be prepared for pulling a calf, as a heifer may need more help than a mature cow. If your cow has had multiple lactations or is a high producer, read up on milk fever and ketosis.
- Don’t forget to prepare for a baby, as well. Sometimes, we get so excited for our cow to calve, we forget about preparing for the calf! (And what to have on hand in case the calf is sick!)