Handling difficult calvings

Calving is covered in classrooms but there’s nothing like real-life initiation. Veterinarian Lisa Freeze thinks of calving as more of an art than a science.

“You can read about in a textbook but it’s something you don’t really figure out on your own until you’re in the middle of things and getting experience, Freeze said.

Calving prep involves a few basics materials: a pail of clean, warm water; a cleaning agent such as chlorhexidine, iodine or a clear, unscented dye-free soap to wash both the cow and your hands and arms prior to checking a cow; clean rags or paper towels; lubricant; rectal sleeves; clean calving chains and handles; and perhaps a calving jack.

Freeze emphasizes the importance of having the cow caught and restrained, especially if the veterinarian has been called. The cow can be haltered and tied or in a chute or headlock. The headlock or chute should open from the side or bottom to decrease the risk of the cow choking if she goes down.

Normal calving occurs in three stages. Stage 1 is cervical dilation, which begins within 24 hours prior to calving. The cow isolates herself, gets up and down frequently, lifts her tail, shows discomfort and passes the cervical mucous plug.

Stage 2 is active labor and ends when birth is completed. This stage usually lasts 30 minutes for cows and 60 minutes for heifers. Stage 3 is placental passing.

“If stage 1 or stage 2 is taking longer than you think it should, put an arm in and check the cow,” said Freeze. “Check her if she’s in stage 1 for more than eight hours and is uncomfortable, if the placenta is coming out but no calf, if the water bag is visible for more than two hours and she isn’t making progress. If she has been in active labor for more than half an hour and isn’t making progress, check her.”

Freeze noted that cows often take short breaks (five to 10 minutes) during labor, but cows taking long breaks should be checked.

Normal calving is “diving position,” with the calf’s front feet first and the head sitting on top of the legs with tips of the feet pointing up.

Freeze discussed the main causes of difficult calving (dystocia).

“The biggest one we see, despite all the progress we’ve made in calving ease, is the calf is too big for the cow or heifer,” Freeze said. “A lot of that can be avoided by choosing the right breed of bull and choosing calving ease bulls. Next is the calf being in the wrong position, but this only accounts for about 5% of calvings.”

Other reasons for difficult calvings include fat, lazy cows, particularly heifers; milk fever; uterine exhaustion; and cervical dilation failure. If the rate of assisted calvings, including heifers, exceeds 5%, Freeze suggested making breeding program changes.

Pulling calves often involves chains, which should be clean and sanitized. “Double loop the chains on both sides of the fetlock joint – above the joint and down below the joint so that you’re spreading out pressure for pulling over a larger space and less apt to injure the legs,” Freeze said.

A calving jack is appropriate when the cow’s cervix is entirely dilated and the calf isn’t making progress. If the cow isn’t dilated, use a jack slowly to avoid ripping the cow’s cervix and vagina.

“The calving jack isn’t a tool to yank a calf out,” said Freeze. “It’s meant to be used to hold the calf at a point so when the cow stops pushing, the calf isn’t sucked back in and losing ground. Generally, we only crank when the cow is pushing or shortly after to help her.”

In some cases, larger calves will present with front legs crossed. This usually indicates an oversized calf with its shoulders squeezed together inside the cow. If your hand is inside the cow and you can’t fit your hand between the calf and the cow’s pelvis, the calf is likely too big and a vet call is warranted.

The rule of thumb is if two strong people or normal, gentle jacking cannot pull the calf out, call the vet. Never try to pull a calf with a tractor or other farm equipment – it can seriously damage the cow and calf.

“If the calf is coming backwards with both legs showing with the tips of the feet pointing down, it might be a backwards calf or an upside-down frontwards calf,” Freeze said. “Work your hands up until you feel the hocks and you can tell whether it’s backwards because what you feel is a hock and not a knee.”

Freeze reminded producers that time is critical with backwards calves: umbilical vessels are compressed and the calf cannot yet breathe through its mouth, so its oxygen supply is cut off.

Calves that are backwards with one or both hind legs down require pushing the calf back in to manipulate it for better presentation. Take care to not puncture the uterus with the calf’s hooves.

A forward presentation with one or both front legs down sometimes requires pushing the calf back in to adjust its legs. For these presentations, it’s a good idea to call the vet to administer an epidural anesthetic.

Sometimes a calf presents frontward with its head back, which Freeze said can be the most difficult to resolve. A properly applied calving snare can help reposition the head. Because the calf’s head may be lodged in the cow’s pelvis, a C-section may be required. Many calves in this position are weak or dead upon delivery.

Uterine torsion can occur and may be missed. While there is no definitive reason for torsion, potential causes include a sudden fall, hoof trimming on a tilt table during late pregnancy or an extremely active calf. Many times there’s no reason at all. A cow with a uterine torsion shows all the signs of calving readiness but nothing is happening.

“The uterus isn’t really anchored to anything,” Freeze said. “Anything that sends the calf for a loop also sends the uterus for a loop and twists it off. As the uterus twists, it also twists off some of the blood vessels that carry oxygen and take away all the metabolites from the uterus. Decreased circulation can lead to a dead calf, compromised uterine tissue and toxins building up in the uterus.”

Fixing a uterine torsion requires rolling the cow with a plank in the correct direction but this requires several people and doesn’t always work. Rolling the cow in the wrong direction can worsen the torsion. A vet can use a detorsion bar to help twist the calf and the uterus in the direction it needs to go, but there’s a risk of breaking the calf’s legs. In some cases, the cervix still isn’t fully dilated after rolling the cow or using a detorsion bar. Take time to get the calf out.

Anyone monitoring calving should be aware of the potential problems, but most cows calve on their own without complications.

by Sally Colby