Sheep Lambing Calculator

How to Use This Calculator

Enter the date your ewe was bred or the date the ram was introduced to the flock. Select the breed for a more precise estimate — fine wool breeds like Merino run toward the longer end, while hair sheep like Katahdin lamb earlier. Click Calculate Due Date to see the expected lambing date and a full milestone timeline.

Litter size shifts the actual date within the normal range — ewes carrying twins or triplets often lamb a few days earlier than ewes carrying a single lamb.

Lambing Kit Checklist

• Iodine for navel dipping
• Clean towels for drying newborn lambs
• Bulb syringe for clearing airways
• OB gloves & lubricant for assisted deliveries
• Lamb feeding tube & colostrum replacer as backup
• Heat lamp or warming box for cold-weather lambing
• Digital thermometer to check for hypothermia

Signs of Lambing

• Hollow flanks: a visibly sunken area on either side of the spine as the ewe stops eating in the final hours.
• Sunken ligaments on either side of the tailhead — one of the most reliable short-term signs.
• Pawing at the ground and nest-building behavior.
• Restlessness and repeated lying down and standing.
• Separation from the flock as birth approaches.

Lamb Care, Hypothermia & Special Situations

Clear the lamb's airway immediately, dip the navel in iodine, dry the lamb thoroughly, and ensure it nurses colostrum within the first 2 hours — a lamb that won't nurse needs tube-fed colostrum promptly.

Hypothermia is a leading cause of early lamb loss. A lamb below 100°F needs warming (towels, a warming box, or heat lamp) before feeding; below 94°F is an emergency requiring veterinary attention.

Triplet management: ewes rarely produce enough milk for three lambs — monitor weight gain closely and be prepared to supplement or foster the smallest lamb if needed.

Grafting orphan lambs works best in the first 24–48 hours: rub the orphan with birth fluids or a deceased lamb's scent, restrain the foster ewe if needed, and supervise early nursing attempts closely.

Lambing Season — NZ, UK and US

In the UK, lambing typically peaks February–April. In New Zealand, where seasons run opposite to the Northern Hemisphere, lambing peaks July–October depending on region — see our sheep gestation calculator for full New Zealand-specific lambing season details. In the US, spring lambing (March–May) is most common, though accelerated or fall-lambing systems exist in some operations.

Breed-Specific Lambing Periods

How Sheep Compare to Other Livestock

Frequently Asked Questions

Sources & References

• USDA — Sheep and lamb production data
• Penn State Extension — Sheep reproduction and lambing management
• Merck Veterinary Manual — Ovine reproduction

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