Sheep Lambing Calculator

Lambing Supplies Checklist

Have this kit assembled and within reach at least a week before the predicted lambing date — most lambing happens with little warning once active labour starts.

Setting Up the Lambing Jug

A lambing jug (an individual pen) gives a ewe a quiet, contained space to lamb and bond with her lambs away from the rest of the flock. Move a ewe into a jug as soon as she shows strong signs of imminent labour, or immediately after she lambs in a group pen. The jug should be:

• Roughly 5×5 feet (1.5×1.5 m) — large enough for the ewe to lie down and turn around, small enough to keep her near her lambs
• Bedded deeply with clean, dry straw — not shavings, which can be inhaled or eaten by newborns
• Draft-free and dry, ideally with a heat lamp positioned in one corner only so lambs can move away from the heat if needed
• Fitted with fresh water and hay/feed the ewe can reach without leaving her lambs
• Kept ewe and lambs together for 24–48 hours before returning them to the main flock, to allow bonding and confirm all lambs are nursing well

Signs Lambing Is Imminent (Final 24–48 Hours)

• Hollow flanks: a visibly sunken area on either side of the spine as the ewe stops eating in the final hours.
• Sunken or softened ligaments on either side of the tailhead — one of the most reliable short-term signs; most ewes lamb within 12–24 hours once these are noticeably soft.
• Udder filling and waxing — the udder becomes tight and full, and wax caps may appear on the teat ends in the last day or two.
• Vulva swelling and discharge — a swollen, reddened vulva with increasing clear mucus.
• Pawing at the ground and nest-building behavior.
• Restlessness with repeated lying down and standing, and general discomfort.
• Separation from the flock as birth approaches — a ewe that isolates herself is often close to labour.

The Stages of Labour in Sheep

• Stage 1 — Cervical dilation (2–6 hours): largely unnoticed from the outside. The ewe becomes restless, isolates herself, paws at the ground, and may get up and lie down repeatedly as the cervix dilates and the lamb rotates into position.
• Stage 2 — Active delivery (30–60 minutes per lamb): begins once visible, strong abdominal straining starts. The water bag typically appears first, followed by the lamb's front feet and nose. Delivery of a single lamb from the start of hard pushing should take well under an hour.
• Interval between lambs (15–45 minutes): with twins or triplets, expect a pause of roughly 15–45 minutes between lambs while contractions resume for the next one.
• Stage 3 — Passing the placenta (2–4 hours, up to 8–12 hours): the placenta normally passes within 2–4 hours of the last lamb being born. A retained placenta beyond 12–24 hours needs veterinary attention.

When to Intervene or Call the Vet

• A ewe strains actively for more than 30–45 minutes without any visible progress
• You can see a leg or nose but delivery hasn't progressed further after 45–60 minutes
• You feel a malpresentation you cannot correct yourself — a leg back, head turned, or a breech (backwards) lamb
• The ewe stops contracting altogether mid-labour and appears exhausted before all lambs have arrived
• Greenish or foul-smelling discharge appears before or during delivery
• The placenta has not passed within 12–24 hours of the last lamb being born
• A ewe shows signs of ringwomb (straining with no cervical dilation) or pregnancy toxemia (dullness, weakness, reduced appetite) in the run-up to labour

Immediate Newborn Lamb Care

The first hours after birth determine most of a lamb's chance of survival. Work through these steps as soon as each lamb is delivered:

• Clear the airway immediately — wipe membranes from the nose and mouth, and gently swing the lamb if fluid needs clearing.
• Dip the navel in 7% iodine tincture within minutes of birth, fully covering the cord, to prevent joint-ill and navel infections.
• Dry the lamb thoroughly with clean towels — a wet lamb loses body heat rapidly, and hypothermia is one of the leading causes of early lamb loss.
• Keep the lamb warm — a heat lamp or warming box for chilled lambs, and a draft-free, dry pen for all newborns.
• Get colostrum into the lamb within the first 2 hours, and again within 12 hours — colostrum provides both energy and passive immunity, and delayed intake is strongly linked to poor survival.
• Watch for hypothermia: a lamb below 100°F needs warming before feeding; below 94°F is an emergency requiring veterinary attention, since feeding a lamb too cold to digest can be dangerous.

Common Lambing Complications

• Dystocia and malpresentation: the most common serious complication. A leg turned back, the head turned to the side, or a breech (backwards) lamb can block delivery. First-lambing ewes and ewes carrying a single large lamb are at higher risk. Gentle correction within a few minutes is often possible; if not, call the vet.
• Ringwomb: the cervix fails to dilate fully during Stage 1, so the ewe strains but nothing progresses. This cannot be corrected by hand in most cases and typically needs veterinary intervention, sometimes a caesarean.
• Pregnancy toxemia (twin lamb disease): develops in the final weeks of gestation, usually in ewes carrying multiples, when energy intake can't keep up with the lambs' demands. Untreated, it progresses to weakness and recumbency and can complicate or trigger difficult labour — watch for dullness or reduced appetite in late pregnancy.
• Mismothering and rejection: a ewe that walks away from, butts, or refuses to let a lamb nurse. More common with first-time mothers, triplets, or after a difficult birth. Confining ewe and lambs together in a lambing jug and supervising early nursing attempts usually resolves it.

Post-Lambing Care for the Ewe

• Nutrition: increase feed quality and quantity immediately after lambing — lactation, especially for twins or triplets, demands significantly more energy and protein than late gestation.
• Watch for mastitis: check the udder daily for heat, swelling, hardness, or discoloration, and watch for a ewe that won't let lambs nurse from one side — early treatment prevents permanent udder damage.
• Watch for a retained placenta: the placenta should pass within 2–4 hours of the last lamb; if it hasn't passed within 12–24 hours, call the vet, as retention can lead to infection.
• Bonding and mismothering prevention: keep the ewe and her lambs together in the lambing jug for 24–48 hours, minimize handling that could interfere with scent-based bonding, and confirm every lamb is nursing before returning the group to the main flock.

Frequently Asked Questions

Sources & References

• Merck Veterinary Manual — Ovine parturition and dystocia
• Penn State Extension — Sheep reproduction and lambing management
• Alabama Cooperative Extension System — Lambing and newborn lamb care
• USDA — Sheep and lamb production data

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