• 5 Questions

• The World According to
   HOOTER McCormick

• RAA Commercial Breeder
  Of The Year

• The Basics Part 1

• The Ease Factor

• The Rewards Of Hard Work

• WC Retrospective

EDITORIALS

• TRAILS
• GAP

During the late 1960’s when we calved in April on our ranch, with cows at pasture (only observed a few times during the day), we averaged a 4 percent annual birth loss—everything from malpresentations or slow birth (calf too large) to coyotes, or a first-time mama not mothering her calf, or even something simple like the sac over the calf’s head not breaking (and he suffocates). In the early 70’s we moved our calving back to January to avoid the mud and scours of March-April, and to have the cows bred before going to summer range in May. Cold weather calving necessitated putting cows in the barn to calve, and we were there for nearly every birth. In 35 years of winter calving, our birth loss dropped to less than 1 percent (0.3 percent); most years we’ve lost NO calves, thanks to being there for nearly every birth—and learning what’s normal and what’s not, and when to help a cow or heifer.

Stages of Normal Labor
Even though birth is categorized into 3 stages (early labor, active labor, and shedding of the placenta) these stages don’t begin or end abruptly but instead gradually move from one to the next. The changes that take place during first stage labor are not outwardly visible, but are preparing the birth canal and calf. The cervix changes so it can relax and open. Uterine contractions begin, and this mild pressure stimulates the calf to move into position for birth and extend his front legs. Contractions also start a softening of the placental attachments so they can more readily separate from the uterine lining, in preparation for shedding the placenta after birth.

In early labor the cow is alert and may be restless as uterine contractions begin. She may leave the herd to find a secluded spot. A confined cow may pace the fence. Even if she’s lying down chewing her cud and doesn’t bother to get up, she’s more alert than usual. It’s her instinct to be aware of any prowling predator that might be a danger to the calf she’s about to have.

She may show intermittent signs of discomfort as contractions occur, switching her tail and kicking at her belly, or getting up and down. These first brief moments of uneasiness occur every 10 to 15 minutes, gradually coming at shorter intervals during the last 2 hours of early labor. Some cows, especially easy calvers, may show few external signs of early labor, and unless you are very observant you might not realize they’re calving. This is why it’s important to observe cows awhile at each check, rather than one quick look. If you only watch the herd for a moment or so, you will miss some that are in early labor because they are acting completely normal between contractions.

Every time a contraction occurs, the cow feels a small, sharp pain. The wave starts at the bottom of the uterus (low and forward in the abdomen) and moves along the entire uterine wall like a swallowing motion, putting pressure on the calf. He starts to wiggle and squirm, which helps him straighten his head (which has been curled around toward his side), and his legs (which have been bent underneath him, due to lack of space in the uterus by the time he’s large and full term). If he’s not lying in proper position when labor begins, the contractions push and stimulate him to move, and the shape of the uterus helps aim him toward the cervix. One reason some cows take longer in early labor is that it’s taking more time to get the calf positioned for birth. The cow may get up and down a lot, which helps rearrange the calf as he works toward proper position.

As the calf and fluid-filled membranes around him get pushed against the cervix, this cone-shaped structure shortens and dilates, making the uterus and vagina one continuous canal. Often the water bag is the first thing to come through the cervix, pushing ahead of the calf and helping open the cervix more fully. The pressure it creates against the cow’s pelvis stimulates release of hormones that make uterine contractions even stronger, and also stimulates her to arch her back and strain a little (voluntary straining with abdominal muscles). She may strain for just a moment, but may keep her back arched and her tail slightly out, due to the discomfort. This is one of your most obvious clues that she’s calving. Even if she’s not visibly straining, her tail is out a little. A cow always holds her tail out when urinating and passing manure (which she does frequently in early labor, due to restlessness and to make more room for the calf to come through the birth canal without the bulk of a full bladder or colon), but instead of going back into normal position the tail stays out a little, especially if she’s walking around.

Active (second stage) labor, from the time visible straining begins (or the water bag appears or breaks) until birth of the calf lasts about 70 minutes, on average, but may take 20 minutes to 4 hours. It usually takes longer in heifers than in cows who’ve had calves before. Active labor begins when some part of the calf comes through the cervix to enter the birth canal. This pelvic pressure stimulates the cow to strain with her abdominal muscles, which forces the calf against the dilating cervix.

She now becomes more focused on her internal pains and more oblivious to her surroundings. Most cows lie down at this point and start a series of hard straining. The calf’s feet push through the cervix, then his head presses against it each time the cow strains, opening it more fully. The water bag often breaks as it is pushed ahead of the calf through the birth canal. It may protrude from the vulva as a maroon-colored balloon about the size of a basketball, or may break before it appears, and you’ll just see a flood of amber fluid gushing out. Sometimes, however, the water bag comes alongside or even after the calf. If you wait for the water to break (for timing the length of second stage labor) you may not judge it correctly.

The water bag is not to be confused with the clearer, whiter amnion sac that encases the calf and is filled with lighter colored, thicker fluid. It is often still intact when it protrudes from the vulva, and the calf’s feet should be visible within it. If the birth is slow, however, the amnion sac may be visible quite awhile, with no feet inside it. This is a hint you should check the cow, especially if the fluid in the sac is dirty yellow-brown, which means the calf has defecated into the amniotic fluid due to pressure on his abdomen or shortage of oxygen. In this instance he needs to be born SOON.

If all is normal, the cow makes steady progress once the amnion sac or feet appear. Usually one front foot is a little ahead of the other as the shoulders come through the pelvis one at a time. It may take hard straining to pass the head; the vulva must stretch to allow the forehead through. Once the head is passed, the rest of the calf usually emerges swiftly. As the ribcage comes through, fluid emerges from the calf’s nose and mouth, pressed out by all the pressure on his chest. This helps clear his airways so he can take his first breath. He curls around toward the cow’s hind legs as he slides on out.

His hind legs may remain in the birth canal a moment, until the cow gets up or he struggles around. If the umbilical cord is not yet broken, he may lie there a moment before he starts to breathe. If it breaks on the way out, he may start trying to breathe very soon. He generally raises his head and shakes it, to help clear his nostrils. When the cord breaks, the umbilical blood vessels are ruptured and retract back toward or into the calf’s abdomen, with very little bleeding. The calf is stimulated to breathe when his nostrils are uncovered and he feels air on his face. About 20 percent of calves are born with the amnion sac still intact, often with fluid still in it. If this sac doesn’t break, he won’t take a breath. This “immersion reflex” keeps him from drawing fluid into his lungs and drowning. But it also means that some calves die soon after birth if the sac does not break or the cow does not start licking it off and nudging him around to get him moving and breathing. If both of them just lie there, the calf goes too long without oxygen and suffocates.

Third stage labor is when the cow sheds the placenta. This usually takes 1 to 3 hours after the calf is born, but sometimes longer. Continued uterine contractions open the cups on the uterine lining so they’ll let go of the corresponding attachments on the placenta. The uterus starts to shrink up and push out the detaching placenta. When part of the placental mass starts through the birth canal this stimulates the cow to add abdominal straining to the uterine contractions, which helps expel the placenta.

When to Check a Cow or Help With Birth
Being able to recognize the normal stages and birth progress helps you judge whether a cow or heifer needs help. It’s important to know how long, and in what circumstances, to leave her laboring on her own and 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 tends to 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 is programmed to open 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 the uterine contractions and from the constricted area in the birth canal. Each time the cow strains, her abdominal contractions put pressure on and constrict 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, he won’t be able to shiver to keep himself warm if he’s short on oxygen in his muscles, and is more at risk for chilling or freezing than a calf born quickly and easily. A calf that spends minimal time in the birth canal is more lively and strong, able to get up quicker and find the udder.

If nothing shows after a cow starts 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 the 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 6 to 8 hours, or is straining hard for more than 1 hour with nothing showing, or if the feet show when she strains but then go back in, or the amniotic fluid has turned brown, or the feet of the calf look upside down, or if only one foot appears, or the progress of the calf has halted.

To check a cow, restrain 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. Wear a short sleeve or sleeveless shirt in case you have to insert your whole arm into the cow to find what’s wrong. Since the cow may defecate several times during your exam, bring extra wash water for rinsing her (and your arm) again. 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 if you need to rinse her or your arm again if she covers it with manure. Coat your hand/arm or OB sleeve with obstetrical lubricant. Insert your hand slowly and gently. 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 awhile for assistance (waiting for the vet) 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. If you decide to go ahead and correct a problem yourself or pull the calf, then you can 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 right there, but are large and he’s just taking too long to come through. Feel a little farther to make sure the head is coming. The nose should be a few inches farther in, with the head resting above the legs. If the head isn’t there, or there’s nothing in the birth canal yet, reach farther in. The birth canal is a long tunnel through soft folds of tissue, with the cervix separating it from the uterus. If you come to the cervix and you can put your hand through it, it’s dilated and the calf should have been starting through. There must be some reason he’s not coming. Reach on into the uterus to try to feel the calf and which way he is lying.

If the cervix is not fully dilated yet, it will be a smaller opening in the end of the long “bag” (birth canal) and may still have some sticky mucus in it. If 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 it. 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 or if you’ll need your vet to do a C-section. If when the calf’s head is starting through the cow’s pelvis there is not room to force your fingers between his forehead and the pelvis, he won’t fit, and you should call the vet.

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, or abnormal aspects of the calf such as birth defects like 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.

Death of a Calf During Birth
The calf may die at any time during labor if the placenta detaches, and it will always start to detach after a long labor. If the cow is not assisted and the calf can’t be born, he generally dies after 3 to 12 hours of active labor, and by that time the cow or heifer may be exhausted and not straining anymore. The open cervix allows pathogens to enter the uterus and start multiplying in the tissues of the dead calf, producing gas and swelling—the dead calf will be quite swollen within 24 hours after the beginning of active labor. Trying to get a dead calf out can be risky and difficult, since the cervix is closing and the calf is swollen. This is a life-threatening situation for the cow/heifer and you’ll need veterinary assistance. This should never happen, however, if cows are being observed at calving time, so you’ll know when the cow began active labor and can help her in a timely fashion.

Restraining a Cow for Checking
If there are no feet showing yet, the cow or heifer will be quite mobile and you’ll probably need to put her in a head catcher or tie her up for checking. Once the calf is in the birth canal, however, the cow or heifer is more apt to continue lying down if you come up behind her, and if she’s gentle she may let you check her right where she is. Usually, however, it’s safest to restrain her. If you tie her with a halter, use a long enough rope that you can keep hold of it and dally it around a corral post or solid barn support, then take up slack until you can tie her properly. Tie short and low. You don’t want so much slack in the rope that she can sling herself around while you’re trying to check her. If you tie too high, she’ll be pulling downward on the rope and be more apt to end up on the ground while you are still trying to check her. If the rope is tied low, she’ll be pulling upward against it and remain standing (which makes checking her much easier). If she does go down, you want the rope tied low so she won’t be hanging by her head.