From ram turn-in to lambing
The Merck Veterinary Manual gives the ewe's estrous cycle as 17 days on average and gestation as 147 days. Two cycles are 34 days, so a ram turned in for 34 days gives most ewes two chances to settle. The table uses 2026 as the breeding year.
| Ram in on | Ram out after 34 days | First lambs due | Last lambs due |
|---|---|---|---|
| Aug 15, 2026 | Sep 18, 2026 | Jan 9, 2027 | Feb 12, 2027 |
| Sep 15, 2026 | Oct 19, 2026 | Feb 9, 2027 | Mar 15, 2027 |
| Oct 15, 2026 | Nov 18, 2026 | Mar 11, 2027 | Apr 14, 2027 |
| Nov 15, 2026 | Dec 19, 2026 | Apr 11, 2027 | May 15, 2027 |
Enter any single date in the sheep gestation calculator, or use the sheep gestation chart. Sheep are short-day breeders, so the breeding season depends on breed and latitude.
Breeding and pregnancy checks
- A ram to ewe ratio of 1 to 40 is enough on average, according to Merck.
- Ewes should be at 60 to 65% of their mature body weight before breeding.
- Pregnancy can be confirmed by transabdominal ultrasound or a blood test about 30 days after breeding. The best time to count the lambs is 40 to 70 days after breeding.
At lambing
| Event | Guide |
|---|---|
| First lamb | Should be born within one hour of strong abdominal contractions starting |
| Lamb stands and nurses | Within 30 minutes of birth |
| Navel | Dip in 7% strong iodine at birth and dry promptly |
| Placenta | Should pass within 12 hours after the last lamb |
| Colostrum, lambs needing extra care | At least 10% of body weight in high-quality colostrum in the first 24 hours |
Signs that lambing is close are udder development, behavior changes such as isolating herself, calling and nesting, and vulval discharge.
Supplies to have ready
- Strong iodine for navels, clean towels and a clean place for each ewe.
- Obstetric lubricant and disposable gloves, and your vet's number.
- A way to give colostrum to a lamb that cannot nurse, shown to you by your vet or an experienced shepherd.
See a vet. If a ewe has strained for an hour without progress, a lamb is not presenting normally or a lamb will not stand and nurse, call your vet. Do not pull hard on a lamb.
Frequently asked questions
How long are sheep pregnant?
An average of 147 days, about five months.
How long does the lambing season last?
A 34 day ram turn-in, two 17-day cycles, gives a lambing window of about five weeks.
When should a newborn lamb nurse?
It should stand and nurse within 30 minutes of birth.