Ewe Nutrition During Pregnancy: Feeding for Lamb Health

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-08-14

Key Takeaways

• Ewe nutrition during the final trimester (last 6-8 weeks) is paramount, as approximately 70% of fetal growth occurs then, directly impacting lamb birth weight, colostrum quality, and subsequent lamb survival.
• Body Condition Scoring (BCS) on a 1-5 scale is critical at breeding (ideal 3.0-3.5) and 4 weeks pre-lambing (ideal 2.5-3.0); thin ewes (BCS < 2.5) yield lighter lambs and less colostrum, while over-conditioned ewes (BCS > 3.5) face increased risks of pregnancy toxemia and dystocia.
• Late gestation presents a physiological challenge where increased fetal demand outstrips the ewe's reduced rumen capacity; this necessitates a shift to more energy-dense rations, typically by gradually introducing grain (0.25-0.5 lbs/ewe/day initially) to prevent acidosis.
• Pregnancy toxemia (ketosis) is a metabolic disorder triggered by negative energy balance in late gestation, often exacerbated by sudden feed changes, weather stress, or insufficient feed access, and is best prevented through consistent, high-energy feeding and monitoring.
• Adequate trace mineral supplementation, particularly selenium and iodine, is crucial for fetal development and preventing conditions like white muscle disease, and a sheep-specific mineral mix must be provided free-choice, distinct from cattle formulations due to copper toxicity risks.
• Uninterrupted access to clean, fresh water is non-negotiable; water intake directly influences feed consumption, and reduced intake due to cold or frozen sources in winter can precipitate metabolic issues like pregnancy toxemia.

Feeding a pregnant ewe correctly is the single most important management decision you will make for the upcoming lambing season. The nutrition she receives from breeding through lactation directly determines lamb birth weight, colostrum quality, milk production, and her own ability to rebreed. This guide covers the full gestation period in practical terms, with specific feeding programs, body condition scoring guidance, and warning signs for metabolic problems. It is written for sheep producers managing small flocks on pasture as well as those operating larger confinement operations.

At a Glance

Key takeaways for every flock:

• Body condition score ewes at breeding, mid gestation, and 4 weeks before lambing.
• Thin ewes at breeding have lower lamb birth weights and weaker lambs.
• Overfat ewes have higher rates of pregnancy toxemia and difficult lambing.
• The last 6 weeks of gestation drives most lamb growth.
• Sudden feed changes or weather stress can trigger pregnancy toxemia.
• Always provide free choice minerals with adequate selenium and iodine.
• Fresh, clean water is nonnegotiable. A ewe will not eat well without water.

Understanding Ewe Gestation and Nutrient Demand

Ewe gestation lasts about 147 days, or roughly 5 months. The nutrient requirements of the ewe are not constant across this period. Early pregnancy demands little beyond maintenance, but the final trimester places enormous pressure on the ewe's digestive system and metabolism.

The conceptus, which includes the lamb, placenta, and fetal fluids, grows slowly for the first 100 days. During this time the ewe needs only a modest increase over maintenance feed. Most of the lamb's birth weight is deposited in the last 6 to 8 weeks of gestation. In fact, roughly 70 percent of fetal growth occurs during the final third of pregnancy. This timing is biologically fixed, and your feeding program must match it.

The challenge in late gestation is physical. As the lambs grow, they take up space in the abdominal cavity. The rumen has less room to expand, so the ewe cannot consume as much forage. At the same time, her energy requirements increase dramatically. This creates a situation where the ewe needs more energy but has less physical capacity to eat. The solution is to feed a more energy-dense ration, which means adding grain or other concentrates to the diet.

Body Condition Scoring as Your Primary Tool

Body condition scoring is a hands-on method to assess the fat and muscle cover over the ewe's loin area. It is a more reliable indicator of nutritional status than simple body weight because it accounts for frame size and gut fill. You cannot look at a ewe and accurately judge her condition. You must feel the backbone and the fat cover over the loin.

The standard scale runs from 1 to 5, with 1 being emaciated and 5 being extremely fat. The ideal condition score for most breeds at breeding is 3.0 to 3.5. At lambing, a score of 2.5 to 3.0 is acceptable. Ewes that lamb at a score below 2.5 will produce less colostrum and may have lighter lambs. Ewes that lamb at a score above 3.5 are at higher risk for pregnancy toxemia and lambing difficulty.

To score a ewe, place your hand over the backbone in the loin area, just behind the last rib. Press gently with your fingertips. You are feeling for the spinous processes, which are the vertical bones of the spine, and the transverse processes, which are the horizontal bones. You also want to feel the fat cover over the ends of these bones.

• Score 1: The spinous processes are sharp and prominent. You can easily press your fingers between them. There is no fat cover.
• Score 2: The spinous processes are prominent but smooth. You can feel them with light pressure. There is a thin layer of fat.
• Score 3: The spinous processes are smooth and rounded. You need firm pressure to feel them. There is a moderate fat cover.
• Score 4: The spinous processes are only felt with firm pressure. The transverse processes are smooth and rounded. Fat cover is thick.
• Score 5: The spinous processes cannot be felt even with firm pressure. The loin area feels solid and fat.

Condition score every ewe at three key points: weaning or breeding, mid gestation around day 90, and again 4 weeks before lambing. Write the scores down. This record allows you to sort ewes into feeding groups based on need rather than feeding the whole flock the same ration.

Early Gestation Nutrition

The first 90 days of pregnancy are relatively undemanding. A mature ewe in good condition needs only a maintenance ration plus a small allowance for the growing conceptus. High quality pasture or good grass hay is usually sufficient. If your ewes were in proper condition at breeding, you do not need to feed grain during this period.

The primary goal in early gestation is to correct any condition problems before the last trimester. If a ewe is thin at breeding, you have a narrow window to improve her condition. It is much easier to add condition in the first half of pregnancy than in the last 6 weeks. If a ewe is overfat, you can allow her to maintain or slightly lose condition during early gestation.

For ewes grazing fall pasture, monitor forage quality. Late fall pasture is often low in energy and protein. If pasture is short or poor, supplement with good quality hay. A mature ewe weighing 150 pounds needs about 3.5 to 4.5 pounds of dry matter per day for maintenance. This amount increases slightly as pregnancy advances.

Trace mineral supplementation should begin at breeding and continue through lactation. Selenium and iodine are especially important for fetal development and for preventing white muscle disease in lambs. Use a sheep specific mineral mix, never a cattle mineral. Cattle minerals often contain copper levels that are toxic to sheep. Provide minerals free choice in a covered feeder to protect them from rain.

Mid Gestation Nutrition

From day 90 to day 120, the ewe's energy requirements begin to climb. The lambs are growing more rapidly now, and the ewe's udder is starting to develop. This is the time to assess body condition and sort ewes into groups.

Group 1 consists of ewes in good condition, scoring 3.0 or better. These ewes can continue on quality forage with mineral supplementation. Group 2 consists of thin ewes, scoring below 2.5. These ewes need additional energy, usually in the form of grain. Group 3 consists of ewes carrying multiple lambs, which you may know from ultrasound scanning. These ewes have higher energy demands and should be fed accordingly.

If you have not scanned your ewes for pregnancy and litter size, consider doing so at day 80 to 100. Ultrasound scanning identifies open ewes, which you can cull or manage separately, and tells you which ewes are carrying twins or triplets. This information allows you to target your most expensive feed to the ewes that need it most.

For ewes on pasture, continue to monitor forage availability. As winter approaches, pasture quality declines. Begin transitioning to conserved forage before the pasture is completely exhausted. A sudden change from pasture to hay will disrupt the rumen microbes and can reduce feed intake. Start feeding hay while the ewes still have some pasture access to allow a gradual transition.

Late Gestation Nutrition

The final 6 weeks of gestation are the most critical period in the entire production cycle. This is when the majority of lamb growth occurs and when nutritional mistakes have the most severe consequences. The ewe's energy requirement increases by roughly 50 percent over maintenance during this period. For a ewe carrying twins, the requirement increases even more.

The physical limitation of rumen capacity becomes a real issue in late gestation. The growing lambs compress the rumen, reducing the amount of forage the ewe can consume. At the same time, she needs more energy. The solution is to increase the energy density of the diet by adding grain.

Start introducing grain gradually at about 6 weeks before lambing. Begin with 0.25 to 0.5 pounds per ewe per day and increase by 0.25 pounds every 3 to 4 days. The target intake depends on litter size and ewe condition. A mature ewe carrying a single lamb needs about 0.5 to 1 pound of grain per day. A ewe carrying twins needs 1 to 1.5 pounds per day. A ewe carrying triplets may need up to 2 pounds per day.

Use a grain that is appropriate for sheep. Whole corn, barley, oats, or a commercial sheep ration all work well. Whole oats are a good choice because they are high in fiber and less likely to cause acidosis. Whole corn is energy dense but lower in protein. If you feed corn, consider adding a protein supplement to balance the ration.

Do not make sudden changes to the grain amount. Increase the amount gradually over several days to allow the rumen microbes to adapt. A sudden increase in grain can cause acidosis, which is a painful and potentially fatal condition.

Forage should remain the foundation of the diet. Provide good quality grass hay or legume hay free choice. Legume hays like alfalfa are higher in energy and protein than grass hays, making them a good choice for late gestation. If your hay is poor quality, you may need to increase the grain portion of the ration.

Feeding for Lamb Birth Weight

Lamb birth weight is directly related to the ewe's nutrition in late gestation. Lambs born to ewes that are underfed in the last 6 weeks of pregnancy are lighter at birth and have lower survival rates. The effect is most pronounced in twins and triplets.

The target birth weight depends on breed and litter size. For most medium frame breeds, a single lamb should weigh 8 to 10 pounds, twins 7 to 9 pounds, and triplets 5 to 7 pounds. These are general guidelines, and you should know the norms for your own flock.

Birth weight matters for several reasons. Light lambs have less body fat and less energy reserves. They are more susceptible to hypothermia and starvation. They are weaker and may struggle to stand and nurse. They have a higher risk of disease and a lower chance of survival to weaning.

However, pushing birth weight too high is also a problem. Very large lambs cause difficult lambing, which can injure both the ewe and the lamb. The goal is to achieve adequate birth weights, not maximum birth weights. A ewe in good condition at breeding that is fed a balanced ration in late gestation will produce lambs with appropriate birth weights.

Pregnancy Toxemia Prevention

Pregnancy toxemia, also called twin lamb disease or ketosis, is a metabolic disorder that occurs in late gestation when the ewe cannot meet her energy demands. The ewe's body mobilizes fat reserves, producing ketones that accumulate in the blood. This condition can be fatal if not treated promptly.

The underlying cause is a negative energy balance. The ewe is consuming less energy than she needs, and her body begins breaking down fat to make up the difference. This is most common in the last 4 to 6 weeks of pregnancy, especially in ewes carrying multiple lambs.

Several factors increase the risk of pregnancy toxemia:

• Overfat ewes at breeding. Fat ewes have reduced feed intake capacity and are more prone to metabolic problems.
• Underconditioned ewes that lack body reserves to draw on.
• Ewes carrying twins or triplets.
• Sudden feed changes or feed deprivation.
• Weather stress, especially cold storms that increase energy demands.
• Poor quality feed that is unpalatable or low in energy.
• Lack of access to feed due to competition or overcrowding.
• Dental problems or other health issues that reduce feed intake.
• Lack of exercise, which can reduce rumen function.

The early signs of pregnancy toxemia are subtle. The ewe may separate from the flock, appear dull, and have a reduced appetite. As the condition progresses, she may show neurological signs including teeth grinding, muscle twitching, blindness, and eventually recumbency. A ewe that is down and unable to rise has a poor prognosis even with treatment.

Prevention is far more effective than treatment. Feed a consistent, high energy ration in late gestation. Do not allow ewes to go without feed for more than a few hours. Make sure all ewes have access to feed, especially shy or subordinate animals. Provide shelter from extreme weather. Monitor body condition and adjust feeding accordingly.

If you suspect pregnancy toxemia, contact your veterinarian immediately. Treatment may include oral propylene glycol, intravenous glucose, or in severe cases, induced lambing or cesarean section. The earlier treatment begins, the better the chance of saving the ewe and her lambs.

Mineral and Vitamin Requirements

Minerals and vitamins are often overlooked in ewe nutrition, but they play a critical role in fetal development and lamb health. A deficiency in any essential mineral can reduce lamb survival and growth.

Selenium is essential for preventing white muscle disease, a degenerative condition of the skeletal and cardiac muscles. Lambs born to selenium deficient ewes are at high risk. Selenium deficiency is common in many regions, especially in the eastern United States and parts of the Pacific Northwest. Provide a sheep mineral mix containing selenium, and consider giving an injectable selenium and vitamin E product before lambing if your veterinarian recommends it.

Iodine is necessary for thyroid function and normal fetal development. Iodine deficiency can cause weak or hairless lambs and enlarged thyroid glands. Most commercial sheep minerals contain adequate iodine, but check the label to be sure.

Copper is a trace mineral that is essential in small amounts but toxic in excess. Sheep are much more sensitive to copper toxicity than cattle. Never feed a cattle mineral to sheep. Use a mineral specifically formulated for sheep, which contains appropriate copper levels.

Vitamin A and vitamin E are important for immune function and overall health. Vitamin A is found in green forage and good quality hay. Vitamin E works with selenium to prevent white muscle disease. Vitamin D is synthesized by the skin in response to sunlight, but may be deficient in confinement operations or during long winters.

Provide free choice sheep mineral in a covered feeder at all times. This allows each ewe to consume what she needs. Monitor mineral intake and adjust if consumption seems excessive or inadequate.

Water Requirements During Gestation

Water is the most essential nutrient, yet it is often the most neglected. A pregnant ewe needs clean, fresh water at all times. Water intake directly affects feed intake. A ewe that does not drink enough will not eat enough.

Water requirements increase as gestation progresses. A mature ewe needs about 1 to 2 gallons of water per day in cool weather, and more in hot weather or when lactating. Lactating ewes have the highest water requirements of any stage, needing up to 3 gallons per day.

In winter, water intake often drops because the water is cold or frozen. This reduces feed intake and can contribute to pregnancy toxemia. Provide warm water if possible, or at least ensure that water sources do not freeze. Check waterers daily in cold weather.

Water quality matters. Sheep will refuse to drink contaminated water, and some water sources contain high levels of sulfates or other minerals that can reduce intake. Test well water if you suspect a problem.

Feeding the Ewe at Lambing

The days immediately before and after lambing are a critical transition period. The ewe's nutritional needs change dramatically, and the feeding program must change accordingly.

In the last few days before lambing, some ewes naturally reduce their feed intake. This is normal. Do not force feed a ewe that is about to lamb. Continue to provide the same ration, but do not be alarmed if she eats less.

After lambing, the ewe needs water and feed as soon as possible. Offer her fresh water immediately after lambing. A warm drink of water can help stimulate the digestive system. Offer good quality hay and a small amount of grain within a few hours of lambing.

The ewe's energy requirements increase dramatically with lactation. A ewe nursing twins needs about 75 percent more energy than a ewe in late gestation. Increase grain feeding gradually over the first week after lambing to avoid digestive upset. The ewe should have free choice hay and access to a lactating ewe ration.

Colostrum quality is directly affected by the ewe's nutrition in late gestation. Ewes that are underfed produce less colostrum with lower immunoglobulin levels. This puts lambs at risk for failure of passive transfer, which means they do not receive enough antibodies from the colostrum. Make sure ewes are well fed in the last 6 weeks of pregnancy to ensure adequate colostrum production.

Common Feeding Mistakes

Many producers make the same mistakes when feeding pregnant ewes. Recognizing these errors can help you avoid them.

The first common mistake is feeding the entire flock the same ration regardless of individual needs. Ewes carrying singles, twins, and triplets have very different energy requirements. Thin ewes and fat ewes need different management. Sorting ewes into groups based on condition and litter size allows you to target feed to where it is needed most.

The second mistake is making sudden feed changes. The rumen microbes need time to adapt to new feeds. A sudden change from hay to grain, or from one type of grain to another, can cause acidosis, reduced intake, and even death. Always transition feeds gradually over 7 to 10 days.

The third mistake is ignoring body condition scores. Body weight alone is not enough. A ewe can lose condition while maintaining weight if she is growing or if gut fill changes. Condition scoring is simple, quick, and highly informative. Use it consistently.

The fourth mistake is feeding poor quality forage. Hay that was cut late, rained on, or stored improperly has low nutritional value. Ewes may eat it but still be undernourished. Test your hay for nutrient content, especially if it looks brown, stemmy, or moldy.

The fifth mistake is overcrowding at the feed bunk. Shy ewes may not get enough feed if they are bullied by more aggressive animals. Provide enough feeder space so all ewes can eat at the same time. A general rule is 18 to 24 inches of bunk space per ewe.

The sixth mistake is failing to provide adequate water. Sheep will not eat well if they cannot drink. Check water sources daily, especially in winter when freezing is a problem.

The seventh mistake is ignoring the ram's nutrition. The ram's fertility and libido are affected by his nutrition. Feed the ram well before and during the breeding season, but do not let him get fat. A body condition score of 3.0 to 3.5 is ideal for a breeding ram.

Decision Thresholds for Feeding Adjustments

Knowing when to adjust the feeding program is important. Use these thresholds as a guide.

If body condition scores at breeding are below 2.5, increase energy intake immediately. Thin ewes need to gain condition before the last trimester. Feed a higher energy ration or provide better quality forage.

If body condition scores at mid gestation are below 2.5, increase the grain portion of the ration sooner rather than later. These ewes need to gain condition before the last trimester. Do not wait until late gestation to address the problem.

If body condition scores at late gestation are above 3.5, do not try to reduce condition during the last 6 weeks. It is too late to safely restrict feed. Focus on maintaining condition and providing a balanced ration. Overfat ewes are already at higher risk for pregnancy toxemia, and feed restriction will only increase that risk.

If a ewe is carrying twins or triplets and is in good condition, begin grain feeding at 4 to 6 weeks before lambing. If she is thin, begin grain feeding earlier, at 8 weeks before lambing.

If forage quality is poor, test the hay and adjust the ration accordingly. Poor quality hay may need to be supplemented with grain or a protein source. If hay contains more than 10 percent mold, do not feed it to pregnant ewes.

If ewes are losing condition despite adequate feed, check for health problems. Parasite load, dental issues, and chronic disease can all cause weight loss. Consult your veterinarian if you cannot identify the cause.

Monitoring and Recordkeeping

Good recordkeeping is essential for making informed feeding decisions. You cannot manage what you do not measure.

Record body condition scores for each ewe at breeding, mid gestation, and late gestation. This allows you to track changes and identify ewes that are losing condition. It also helps you evaluate your feeding program from year to year.

Record lamb birth weights. This is the most direct measure of the success of your late gestation feeding program. Low birth weights indicate underfeeding. Excessively high birth weights may indicate overfeeding, especially in singles.

Record lambing ease. Difficult lambing is more common in overfat ewes and in ewes carrying very large lambs. If you see a pattern of difficult lambing, review your nutrition program.

Record the incidence of pregnancy toxemia, abortion, and lamb mortality. These are all influenced by nutrition. A high incidence of any of these problems is a red flag that your feeding program needs adjustment.

Record feed costs and feed consumption. This allows you to calculate the cost per ewe and per lamb weaned. Feeding is typically the largest variable cost in a sheep operation, so controlling feed costs without sacrificing nutrition is important.

Use a simple spreadsheet or a paper record book. The format does not matter as much as consistency. Record data at the same time points each year so you can compare across years.

When to Call a Veterinarian or Extension Agent

Some situations require professional help. Do not hesitate to call your veterinarian or local extension agent when you encounter these problems.

Call your veterinarian immediately if you suspect pregnancy toxemia. A ewe that is dull, off feed, or recumbent in late gestation is an emergency. Early treatment improves the chance of survival.

Call your veterinarian if you see signs of abortion. Abortion storms can be caused by infectious diseases that affect the whole flock. Your veterinarian can help you diagnose the cause and prevent further losses.

Call your veterinarian if a ewe has difficulty lambing. Do not wait too long to intervene. A ewe that has been straining for more than 30 minutes without producing a lamb needs assistance.

Call your veterinarian or extension agent if you see a pattern of low birth weights, poor lamb survival, or high rates of pregnancy toxemia. These problems often have a nutritional component that can be corrected with professional advice.

Call your extension agent for help with ration balancing, forage testing, and body condition scoring. Extension agents have access to resources and can help you develop a feeding program specific to your flock and your feed resources.

Call your veterinarian if you are unsure about mineral supplementation. Selenium and iodine requirements vary by region, and your veterinarian can advise you on the appropriate supplementation program for your area.

Frequently Asked Questions

How much grain should I feed a pregnant ewe in the last month?

The amount depends on the ewe's body condition and the number of lambs she is carrying. A mature ewe in good condition carrying a single lamb needs about 0.5 to 1 pound of grain per day. A ewe carrying twins needs 1 to 1.5 pounds per day. A ewe carrying triplets may need up to 2 pounds per day. Start with a small amount and increase gradually over several days to prevent digestive upset.

What are the signs of pregnancy toxemia?

Early signs include separation from the flock, dullness, and reduced appetite. As the condition progresses, the ewe may grind her teeth, have muscle twitching, appear blind, and eventually go down and be unable to rise. Any ewe showing these signs in late gestation should be examined by a veterinarian immediately.

Can I feed cattle mineral to my sheep?

No. Cattle minerals often contain copper levels that are safe for cattle but toxic to sheep. Sheep have a much lower tolerance for copper. Always use a mineral supplement specifically formulated for sheep.

How do I know if my ewe is too thin or too fat?

Use body condition scoring. Place your hand over the loin area, just behind the last rib, and feel for the backbone. A score of 1 means the bones are sharp and prominent. A score of 3 means the bones are smooth and rounded with moderate fat cover. A score of 5 means you cannot feel the bones even with firm pressure. Ideal scores are 3.0 to 3.5 at breeding and 2.5 to 3.0 at lambing.

What is the best hay for pregnant ewes?

Good quality grass hay or legume hay both work well. Legume hays like alfalfa are higher in energy and protein, making them a good choice for late gestation. The most important factor is quality. Hay that was cut early and stored properly has more nutritional value than hay that was cut late or rained on. Test your hay to know its nutrient content.

How soon after lambing should the ewe be fed?

Offer the ewe fresh water immediately after lambing and provide hay and a small amount of grain within a few hours. She needs to start eating and drinking to begin milk production. Increase the grain amount gradually over the first week after lambing as her milk production increases.

Should I feed extra protein to pregnant ewes?

Protein requirements increase during late gestation, especially for ewes carrying multiple lambs. Most good quality hays provide adequate protein for ewes in early and mid gestation. In late gestation, the grain portion of the ration adds protein as well as energy. If your hay is low in protein, you may need a higher protein supplement.

How much water does a pregnant ewe need per day?

A pregnant ewe needs about 1 to 2 gallons of water per day in cool weather. This increases in hot weather and during lactation. Lactating ewes may need up to 3 gallons per day. Always provide clean, fresh water and check water sources daily, especially in winter when freezing is a problem.

Related Farming Guides

This section will be populated with links to other farming guides on this site, including articles on lambing management, ram nutrition, pasture management for sheep, and flock health planning. Check back for updated resources.

Related Clinical & Scientific Guides

• Sheep Grazing Lease: Terms, Rates, and Legal Considerations
• Sheep Breed Selection for Meat, Wool, Dairy, and Low-Input Systems
• Sheep Barn Flooring for Hoof Health: Best Materials and Practices

References

• American Consortium for Small Ruminant Parasite Control (ACSRPC): https://www.wormx.info/
• USDA APHIS Sheep Health: https://www.aphis.usda.gov/livestock-poultry-disease/sheep-goats
• FAO Sheep and Goat Production: https://www.fao.org/animal-production/en/
• FAO Animal Production and Health: https://www.fao.org/animal-production/en/
• WOAH (World Organisation for Animal Health): https://www.woah.org/en/home/

This article is educational and is not a substitute for veterinary diagnosis, treatment, public-health guidance, or regulatory reporting.