Q.

What can go wrong before lambing/kidding?

A.

The list is longer than we'd prefer, but can be mostly prevented with good nutrition and management. Nutritional requirements increase during late gestation, especially for ewes/does carrying multiple births. There is an increase in the need for both energy (TDN) and calcium (for ewes) in the diet. Protein requirements don't increase substantially until after lambing/kidding (lactation). Good nutrition means meeting but not exceeding the nutritional requirements of the animals. There are consequences to overfeeding.

Besides diet, it's important not to stress ewes/does during late gestation. They should not be handled too close to term, especially if they are not used to being mustered. Ewes should not be sheared too close to lambing. Vaccinations and any deworming should be done about a month before the first offspring are expected. Groups should not be mixed. Exercise should be encouraged but not excessive. Rams/bucks should be housed away from pregnant females. Weather can be a huge stress.

Pregnancy toxemia
One of the most common problems in late gestation is pregnancy toxemia (or ketosis). This disease is also called twin lamb disease because it mostly affects females carrying multiple births. Pregnancy toxemia is caused by insufficient energy in the late gestation diet, resulting in low blood sugar. Besides females carrying multiples, fat and thin ewes/does are the most likely candidates. The first sign of pregnancy toxemia is a ewe/doe that lags behind the flock or is slow to come to the feed trough. She is lethargic. She may grind her teeth. She may have poor muscle control. In latter stages of the disease, the female goes down and is unable to rise. There is sometimes a mucous discharge (or foam) from the nose. Diagnosis can be confirmed with blood or urine tests.

Early stages of pregnancy toxemia can be treated with propylene glycol or other quick sources of energy (e.g., molasses, corn oil). Affected females should be drenched several times a day with the energy solution. Later stages of the disease require glucose via an IV. In some cases, induced lambing/kidding or a caesarian section is necessary. Like most diseases, early recognition and treatment is key. Pregnancy toxemia should be suspected any time a late pregnant ewe/doe appears sick.

Pregnancy toxemia is prevented by providing sufficient energy in the late gestation diet. To meet the increased needs for energy, it is customary to feed some grain. Grain is a more concentrated source of energy than hay or other forages. The amount of grain needed depends on the size (weight) of the female and the number of fetuses she is carrying, as well as the quality of the forage in the diet. Having ample feeder space is also important, as grain is usually limit fed. Older, younger, or more timid females may not get enough to eat unless there is sufficient bunk space.

Milk fever (hypocalcemia)
Milk fever occurs mostly in late gestation and is usually the result of a diet deficient in calcium. Milk fever can also occur after parturition and be the result of a diet too rich in calcium. The signs of milk fever are similar to pregnancy toxemia.It's not uncommon to treat females simultaneously for both pregnancy toxemia and milk fever. Response to treatment confirms the diagnosis of milk fever. A blood test can confirm low calcium.

Ewes are usually given calcium borogluconate via an IV. The calcium should be injected very slowly. The response is usually dramatic. More marginal cases of milk fever can be treated with calcium via sub-cutaneous injections. There are also oral drenches and gels that can be given to provide additional calcium.

Milk fever is prevented by providing the proper amount of calcium in the late gestation diet. Legumes are a good source of calcium. In some cases, they contain too much calcium and should be saved for the lactation diet. Poor quality grass hays may be deficient in calcium. Grains and oilseeds are poor sources of calcium. Limestone is the best source of calcium. Kelp is a good source, too. Free choice minerals do not ensure adequate calcium intake. It's better if the calcium is incorporated into the ration.

Vaginal prolapse
Some females (sheep more than goats) prolapse their vaginas in late pregnancy. There are many contributing factors. Ewes that prolapse their vaginas should probably not be retained, as there is a strong likelihood they will do it again. Because it is a heritable condition, their offspring should probably not be kept (or sold) for breeding.

Prolapses need to be replaced as soon as possible to prevent more serious problems. The exposed part needs to be cleaned with warm, soapy water and pushed back into the female. The prolapse can be kept in place by using a bearing retainer (or "spoon") and/or prolapse harness. Homemade harnesses can be made from baling twine and tied to the sheep's wool. Sometimes, the prolapse is kept in with a suture. Ewes/does can push their lambs/kids through the retainers and harnesses, but the suture needs to be removed before lambing/kidding. Once the ewe/doe has birthed her offspring, the prolapse usually stays in. Problem solved.

Abortion
Some ewes/does abort their offspring before term. There can be many causes, both infectious and non-infectious. Early term abortions are usually not noticed, and the female usually breeds back. This is how we get some of our late lambs/kids. Late term abortions may result in the birth of premature or full term fetuses (sometimes deformed) or weak lambs/kids that die shortly after birth. Abortion due to infectious causes is a big deal. Veterinary advice should be sought. Treatment and prevention will depend on the cause.


05/08/2021


Additional reading
Pregnancy toxemia (ketosis) in ewes and does - Colorado State University
Pregnancy toxemia in ewes and does - UC Davis
Risk factors of vaginal prolapse (infographic)
Abortion in sheep - Merck Veterinary Manual | In goats