Knowing the due date isn't trivia — it drives when you move an animal to a birthing pen, when you adjust feed, and when you need to be around at 3am. Here's the reference table and the factors that move it.
The chart
| Animal | Average | Typical range |
|---|---|---|
| Cattle | 283 days | 279–287 |
| Horse | 340 days | 320–370 |
| Pig | 114 days | 112–116 |
| Goat | 150 days | 145–155 |
| Sheep | 147 days | 144–152 |
| Llama / alpaca | 340 days | 320–360 |
| Rabbit | 31 days | 28–33 |
| Dog | 63 days | 58–68 |
| Cat | 64 days | 60–67 |
We have due-date calculators for cattle, goats and sheep that take the breeding date and return the expected date plus the range.
What actually moves the date
Litter size. The strongest factor in multiple-birth species. Ewes carrying twins or triplets typically lamb earlier than ewes with singles, sometimes by several days. Same pattern in goats.
Sex of the offspring. Genuinely true and often disbelieved: male calves are carried about a day longer than females on average.
Breed. Meaningful in cattle. Continental breeds like Charolais tend to run longer than British breeds like Angus — often close to a week's difference. Use your breed's figure rather than the species average if you have it.
Age. First-time mothers often carry slightly shorter.
Season and nutrition. Both shift things at the margins. Heat stress and poor body condition can bring dates forward.
Why horses are the awkward one
That 320–370 day range is not a typo — mares have the widest normal window of any common livestock. A 50-day spread is normal, which makes "the date" almost meaningless for horses.
Mares also foal on their own schedule, overwhelmingly at night, and can delay if they don't feel private. Foaling watch is about reading the animal — udder development, waxing, relaxed tailhead — not about the calendar.
Signs to watch for
Across most species the pattern is similar in the final days: udder fills and tightens, the pelvic ligaments relax so the tailhead appears to rise, vulva softens and swells, and the animal separates from the group and gets restless.
Once labour starts properly, it should progress. This is the number that matters most: if an animal is straining hard with no progress for 30 to 60 minutes, call your vet. Waiting is what turns a manageable malpresentation into a dead animal — often two.
Working backwards
The chart runs both ways, and this is how experienced keepers use it. Want spring lambs in early April so they hit grass at the right time? Count back 147 days and put the ram in around mid-November. Want calves born when you're not also cutting hay? Breed accordingly.
Breeding date is the input that makes any of this work, so record it. A guessed breeding date produces a guessed due date, and you'll be doing 3am checks for two weeks instead of three days.
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Frequently Asked Questions
How long is cattle gestation?
About 283 days on average, with a normal range of 279 to 287. Continental breeds tend to run longer than British breeds, and male calves are carried slightly longer.
How long are goats and sheep pregnant?
Goats average 150 days and sheep 147, each with roughly a week either side. Animals carrying twins or triplets usually give birth earlier than those with singles.
What is the gestation period for pigs?
114 days — remembered as three months, three weeks and three days. Pigs are among the most consistent of all livestock species.
Why do horses have such a wide gestation range?
Mares normally foal anywhere from 320 to 370 days, a 50-day spread. Foaling watch relies on physical signs like udder development rather than the calendar.