Cow pregnancy at a glance
| Planning figure | 283 days (about 9.4 months) — the standard used in extension gestation tables |
|---|---|
| Breed differences | Brahman-type breeds run longer: one large study measured about 291.5 days for Brahman, 288 for Droughtmaster and 285 for Santa Gertrudis |
| Bull vs heifer calves | Bull calves are carried about 2–3 days longer than heifer calves |
| Pregnancy confirmed by | Blood test from 26 days; ultrasound from 28 days; rectal palpation from 35–40 days |
| During labour | There should be noticeable progress every 30 minutes |
About the planning window
283 days is the standard planning figure, but real cows vary. In one large study of tropical breeds, individual pregnancies ranged from 271 to 305 days. We show 10 days either side of the due date as a practical planning window; breed, calf sex and genetics all shift the timing.
Signs a cow is close to calving
- Udder fills (“bags up”) and teats swell — called springing.
- Pin drop: the muscles around the tailhead relax.
- Behaviour: restless, getting up and down often, licking her side, moving away from the herd.
Frequently asked questions
How long is a cow pregnant?
About 283 days, a little over 9 months. Brahman-influenced cattle tend to be longer, around 285–291 days.
Why does my calving table use 283 days?
Most university gestation tables use 283 days as the standard planning figure. Real calving dates vary by breed, calf sex and genetics.
When can I pregnancy-check my cow?
A blood test can be used from about 26 days after breeding, ultrasound from about 28 days, and rectal palpation by a vet from about 35–40 days.
Are bull calves born later?
Yes, slightly. Research found bull calves were carried about 2–3 days longer than heifer calves.
Sources
- Oklahoma State University Extension – Calving Time Management for Beef Cows and Heifers (E-1006)
- University of Tennessee Extension – Calving in General
- University of Florida IFAS – Pregnancy Testing Methods on Beef Cattle
- Beef Central – Is cattle gestation really 283 days?
Last reviewed November 2026. This calculator gives estimates for planning only and is not veterinary advice.