Q.

What can go wrong at lambing/kidding?

A.

While most ewes/does lamb/kid on their own without any need for intervention, sometimes problems arise. Many of the problems are caused by poor feeding or management practices. Some problems occur randomly.

Dystocia
Dystocia is the most common problem encountered. Dystocia means difficult birth. Technically, it's when birth takes more than an hour after rupture of the fetal membranes (water bag). Dystocia could be a prolonged unassisted birth or a birth in which assistance was provided. Dystocia causes the death of many ewes/does and lambs/kids. A study conducted in New Zealand showed that dystocia accounted for 50 percent of deaths among newborn lambs. Causes of dystocia are multi-factoral.

There are three primary types of dystocia: fetopelvic disproportion, malpresentations, and complications. Fetopelvic disproportion is when the lamb/kid is too big to get through the pelvic opening. A malpresentation is an abnormal presentation of the fetus(es) at the time of birthing. Complications include ringwomb, uterine prolapse, and retained placenta.

Fetopelvic disproportion is most common with singletons and oversized lambs/kids. Heavier birth weights are only good up to a point. The head, shoulders, and hips are the most difficult parts of the lamb/kid to get through the birth canal. Some big lambs/kids just need a tug or some extra lubricant. Others require more patience and extreme measures in extreme cases.

You can find various diagrams of abnormal presentations with explanations on how to correct them. Some are easy to correct. Others require more patience and manipulation. Normal presentation is the "diving" position: two front feet with the head resting between them. Unless something else is going on, the ewe/doe should be able to deliver these babies on her own. Backwards (hind legs first) can also result in a normal birth, though there is some risk of suffocation if the umbilical cord breaks before the head is out. It's best to pull a backwards baby out if you see one.

Breech is different than backwards. In a breech birth, the rear is coming first, but the legs are still in the uterus, tucked under. Only the tail may be present in the birth canal. The ewe/doe cannot deliver a breech baby on her own. She needs help. The baby should not be turned around. It should be delivered backwards once the hind legs have been extended into the birth canal. In order to do this, you usually have to push the baby further back into the uterus. Breech births are a little tricky, but can be handled with a little experience (and confidence).

Elbow locks and one or more legs back are the most common malpresentations and the easiest to correct. Heads can present more difficult challenges, especially when the head is twisted back in the birth canal, in which case it must be righted before the baby can be delivered (easier said than done). If just the head is sticking out of the vulva, it is usually necessary to return the head to the birth canal, unless there is one leg out and the baby can be pulled out without extending the other leg. Swollen heads can present some challenges, as they can be difficult to push back in. Fortunately, those swollen, gross-looking heads can survive for quite long periods of time in the “hung” position.

Ringwomb
Various complications can cause difficult births. One of the most troublesome is ringworm. Ringwomb is when the cervix fails to dilate. A successful outcome is usually only achieved with a caesarian section. If the cervix is partially dilated (“false” ringwomb), it may be possible to manually stretch the cervix to get the baby out. The female may also respond to drugs (smooth muscle relaxants, calcium). False ringwomb is sometimes caused by premature intervention. True ringwomb is not fully understood, though there seems to be a genetic component, so it's best not to keep affected ewes/does and their offspring.

Prolapsed uterus
One of the most dreaded sights in the lambing barn is a uterine prolapse. The everted uterus presents as a large mass of tissue hanging from the vulva. The caruncles (raised circular areas where the placenta was attached) are visible. A uterine prolapse may occur immediately after birth or 12 to 48 hours later. It is a life threatening situation. The prolapsed uterus must be cleaned and gently pushed back through the vagina. It must also stay in. That is easier said than done. A uterine prolapse is best replaced by a veterinarian with epidural anesthesia. Unlike a vaginal prolapse, a ewe is unlikely to prolapse her uterus the following year and there is no need to cull her or her offspring.

Retained placenta
The final stage of parturition is cleaning or expolsion of the placenta (afterbirth). Normally, it is expelled in the first several hours after birth. If the placenta is still attached after 12 hours, there may be a problem. It's okay to give the placenta a light tug, but it should not be forceably pulled, as it may still be attached to the uterus. Treatment for a retained placenta is usually antibiotics. Some veterinarians adovcate oxytocin or prostaglandins.


05/10/2021


Additional reading

Assisting the ewe at lambing - Ontario, Canada
A Review of Dystocia in Sheep - Small Ruminant Research
Lambing/Kidding and Difficult Births (Dystocia) - InfoVets
Occurrence, etiology, and management of ringwomb in ewes