by Sally Colby
When there’s trouble during a calving, someone on the farm is usually willing and able to don an obstetric sleeve and help that cow safely deliver the calf. But the decision to assist a cow should be a part of careful observation skills and overall good cow sense.
Penn State Extension Veterinarian Dr. Robert Van Saun says one essential part of a successful calf delivery is the ability of the producer to observe cows and identify early stages of labor. “You don’t want to lose track of close-up cows,” he said. “It’s easy to get busy with other farm tasks and neglect the cow that is close to calving.”
Van Saun says that ideally, cows are moved into maternity pens only when they’re close to calving — especially if the farm is limited in pen size or availability. “We want to have a process where the environment is stress-free and monitored frequently, cows are easy to catch, there’s good footing and single-use maternity pens that are clean and dry,” he said. “Then we can identify the cow that is getting ready to calve.”
Understanding the stages of labor is critical to successful deliveries. “In stage one, the cow isolates herself, the ligaments in her hindquarters loosen, the tailhead lifts, and there may be a clear mucous discharge,” said Van Saun. “This stage can vary in time, so you don’t want to be too aggressive in helping. Heifers take longer to go through stage one. Stage two is the actual delivery, when the cow has strong contractions every minute or so, and the fetus passes through the birth canal. The average time in from onset of labor to delivery is about 70 minutes. The third stage is the passing of placenta, or fetal membranes.”
Van Saun reminds producers that there are two water bags, and cautions against breaking the first water bag. “People see the first bag coming out and think it’s the second bag,” he said. “That first bag has a purpose — it helps stretch the cervix and loosens the birthing canal. If you break the first water bag, you’ve broken down the hydraulic pressure that helps stretch and prepare the cow for calving. The second water bag is the one that surrounds the fetus, and can be broken once it’s presented.”
Once the cow is in heavy labor, the process should continue until the calf is delivered. If there’s no significant progression two hours after the first water bag has appeared and the cow is actively contracting, assistance is probably needed. Any cow that is exhibiting lethargic behavior or has ‘stopped trying’ often means that the cow has a uterine torsion or an abnormal calf that prevents it from entering the pelvis. A cow with an abnormal discharge, especially one that’s foul-smelling, likely has a problem.
“If a calf isn’t delivered within a few minutes of the shoulders or chest appearing, be concerned,” said Van Saun. “If the shoulder is caught in the pelvic canal, the umbilical cord is cut off. Unless the calf is actually breathing, its oxygen supply is cut off, resulting in a dummy calf or a calf that doesn’t absorb colostrum well and will be prone to disease.”
Stressed calves are the usually the result of prolonged labor or abnormal presentation. Van Saun says calves that are yellow-brown color at birth are heavily stressed and at risk. “The staining is meconium, from the lower colon,” he explained. “Mother Nature has set up an alarm system — if the calf becomes oxygen-deprived, or anoxic, the colon contracts and pushes the meconium out. The meconium staining is a sign that the calf has had a rough time and needs special attention. That calf will take longer to stand, won’t nurse well, and its efficiency in absorbing immunoglobulin is lower.”
When a cow requires assistance, the first step is to perform a pelvic exam to determine the position of the calf. “Metritis is one of the biggest challenges in reproductive performance, so be sure to be clean and use plenty of lubricant — as much as 10 gallons to induce a rapid deliver,” said Van Saun. “If you have a situation where the water bag broke early and the cow has started to dry out, that’s what you need to do to get the calf out — otherwise you’re going to cause tears.”
When performing the exam, determine the calf size relative to pelvic opening based on the diameter of the hoof or canon bone. Only after an accurate assessment of the calf’s position (and repositioning when necessary) should chains be attached.
To determine whether a presenting foot is a front or a hind, remember that in a front leg, the pastern joint and carpal joint bend inward in the same direction. In the hind legs, the pastern joint and the hock bend in opposite directions. Checking for hooves that point upward or downward isn’t a reliable method of distinguishing a hind from a front leg.
Van Saun emphasizes the importance of looping the calf chains around the hand properly in order to use them most effectively. When pulling a calf, pull straight until the head is out, then pull downward. A head snare, or calf saver, works well in situations in which the head is floppy and aimed back toward the rear of the calf. The snare is placed behind the ears and in the mouth and is used to help guide the head out.
When assisting a birth, remember that the calf’s hooves can feel sharp but are still soft, so be careful with chains. Take care to not scrape the uterine wall, which can cause permanent damage. “Always move things medially, not outward,” said Van Saun as he described how to reposition a calf inside the cow. “You want to bring a leg underneath — otherwise there’s a chance of tearing the uterine wall. Always do the give and take. Your mindset will be ‘get it out,’ but sometimes you have to push the calf back in deeper before it’s ready to come out.”
Close attention at calving time pays off
by Sally Colby