By Heather Smith Thomas – The riskiest time in a calf’s life is being born. Several million calves in the United States and Canada are lost each year during birth or shortly after, and 45 percent of those deaths are because of dystocia (delayed or difficult birth). Almost all birth losses can be prevented, however, by being there to assist a cow giving birth if needed. A cow is pregnant for roughly nine months; average gestation is 283 days, but some cows calve a week or two ahead of schedule, or a week or two later. Cows with shorter-than-average gestation tend to have smaller calves at birth, and fewer calving problems.
You’ll know when she is about to calve when you see calving signs. In early labor the cow is restless, tail held out, getting up and down, and kicking at her belly. Breaking of the water signals the beginning of active labor as the calf starts into the birth canal and abdominal straining begins.
How long should a cow be in labor? It’s important when you’re cattle farming to know how long and in what circumstances to leave her laboring on her own, so you can know when to help her or seek help from your vet. Don’t intervene too soon, before the cervix is dilated, or you may injure her by pulling the calf through that narrow opening. If you pull too soon (and too steadily) a partially opened cervix may be pulled out of place, like a sleeve—pulling it cone-like ahead of the calf and restricting the diameter of the opening. A too-strong pull may tear it. Forceful pulling before the birth canal is ready may rupture the cervix or tear the vagina and vulva. The cervix opens as the calf’s head presses intermittently on it with each contraction; a hard steady pull on the calf can delay this process.
But once the calf is in proper position and the cervix nearly fully dilated, there is no point in waiting, if the calf is taking too long to come through. He is subjected to a lot of pressure from uterine and abdominal contractions and from the constricted area in the birth canal. Each time the cow strains, her abdominal contractions put pressure on the blood vessels to the uterus, resulting in diminished oxygen supply to the calf. If this goes on a long time he may be born weak, unconscious or dead. If he’s born in cold weather and has been short on oxygen, he is more at risk for chilling than a calf born quickly and easily. A calf that spends minimal time in the birth canal is lively and strong, able to get up quicker and find the udder. In either case, it’s always good to know how to tube feed a calf.
If no feet start to show after a cow is straining intensely, check her to see if the calf is being presented normally or not, or whether it’s too large to be born. It’s healthier for both the cow and calf if you can assist the cow before she is fatigued and the calf compromised by being in the birth canal too long. It’s time to check her if she’s been in early labor more than six to eight hours, or is straining hard for more than one hour with nothing showing, or if the feet show when she strains but then go back in (multiple times), or the feet of the calf look upside down, or if only one foot appears, or the progress of the calf has halted.
A good rule of thumb is to give assistance to any heifer or cow that goes beyond one hour in active labor (straining) and the calf is not yet born. Even if the feet and nose are showing after an hour of hard labor, it’s best to go ahead and pull the calf unless visible progress is seen at the end of that hour. If the calf’s tongue is sticking out, labor has probably been too long, especially if the tongue is starting to swell; this means the calf has been in the birth canal too long, subjected to steady pressure.
To pull a calf, first, make sure he is in the proper position, then attach pulling chains to his legs using a half-hitch (one loop above the fetlock joint and the other around the pastern above the hoof). This spreads the pressure better than a single loop and will cause less injury to his legs. Attach handles to the chains and pull when the cow strains, resting while she rests. If you have a helper, that person can stretch the vulva as you pull, making it easier for the head to pass through. Once the head comes through, the rest of the calf should come fairly easily.
If the calf is coming backward, attach chains to the hind legs (double half-hitch) and pull slowly and gradually until the hips are coming through the vulva, then pull the calf on out as swiftly as possible so he won’t suffocate. His umbilical cord is breaking before you get him out, so he needs to come on out quickly so he can start breathing.
Assisting heifers (or a cow, if she needs help) no later than after one hour of active labor results in a more vigorous calf; he’s not weak and exhausted from being in the birth canal too long. Also, heifers that take less than an hour in labor or are helped before they go beyond that golden hour will breed back faster. The reproductive tract returns to normal more quickly (less stress and damage). Proper intervention and assistance at birth can significantly shorten the interval between birth and first heat cycle for the cow or heifer. As a rule of thumb, you can figure that each 10 minutes delivery is delayed adds about two days to that time interval, and some heifers that don’t have help when they need it do not become pregnant again that year.
If you wait too long to help, the calf will die. The heifer or cow may be exhausted by then, and unable to strain productively when you do try to help her. The lubricating fluid around the calf may be gone, if the sacs have ruptured, making assistance more difficult. If she’s already spent too long in labor, the vaginal wall may be swollen, making it harder to put your hand and arm in—and there’s less room to manipulate the calf if he’s in the wrong position. If the cervix and uterus have already started to contract and shrink, correcting a malpresentation becomes very difficult or impossible, so timely checking is crucial.
Checking the Cow or Heifer
Restrain her (in a head catch or stanchion that accommodates a cow lying down as well as standing, or tied with a halter—low enough that if she lies down the rope won’t be “hanging” her) and wash her rear end with warm water. If you don’t have a helper to hold her tail, tie it with a string around her neck, so she’s not continually swatting you in the face with it or flipping manure. Since she may defecate several times during your exam, bring extra wash water for rinsing her and your arm. Putting your hand in the birth canal will make her strain and pass more manure. It’s handy to have extra water in squeeze bottles; they are easy to use with one hand. Coat your hand/arm or OB sleeve with obstetrical lubricant.
If the water bag is in the birth canal, don’t rupture it yet, in case you find a problem you can’t correct and must call the vet. If the cow must wait for assistance it’s best if you don’t let all the fluids escape yet; they will be beneficial lubrication if the calf must be pulled. Also, if the fluids are gone, it’s like emptying a balloon; the uterus will be shrinking down more by the time the vet arrives, leaving less room to manipulate the calf. But if you decide to go ahead and correct a problem yourself or pull the calf, rupture the membranes to get the fluid-filled balloons out of your way so you can manipulate the calf easier and put chains on his legs.
Put your hand into the birth canal as far as needed to find the calf. You may discover his feet are there, but he’s large and taking too long to come through. Feel a little farther to make sure the head is coming. If the head isn’t there, or there’s nothing in the birth canal yet, reach farther in. If you come to the cervix and can put your hand through it, it’s dilated and the calf should be starting through. There must be some reason he’s not coming. Reach on into the uterus to feel the calf and which way he’s lying.
If the cervix is not fully dilated and you can only put one or two fingers through it, the cow needs more time. If it is partially open, you may be able to put your hand through and determine what’s happening with the calf and why his feet are not starting through. If the birth canal ends abruptly at the pelvic brim and is pulled into tight, spiral folds, the uterus may have turned over (torsion of the uterus) putting a twist in the birth canal. If this is the case, call your vet for assistance to correct the torsion. If all you feel is a spongy mass of placenta, coming ahead of the calf, this is an emergency and you must deliver him quickly.
Your assessment of the situation will help you know whether to give the cow more time, call the vet to help you correct a problem, or go ahead and pull a calf that has started into the birth canal in proper position but coming too slow because he’s big. If he’s large, you must make a determination as to whether he can be safely pulled. If when the calf’s head is starting through the cow’s pelvis there is no room to force your fingers between his forehead and the pelvis, he won’t fit, and you should call the vet to do a C-section delivery.
If you can’t decipher the calf’s position, or have worked for 20 to 30 minutes trying to correct a problem and have not been able to correct it or extract the calf, call your vet, unless you can tell you are beginning to make progress. Don’t spend too long in futile efforts, or it may become too late for the calf after you finally decide you cannot get him delivered yourself. Other instances in which you should call the vet are if you feel any abnormalities such as a tear in the birth canal or uterus, abnormal aspects of the calf such as a forehead too large, fused joints—the legs not able to flex to maneuver into the birth canal—or some other problem that would hinder his birth progress.
Have you assisted a cow giving birth? What tips do you have for success? Let us know in the comments below.