Determining when and how to intervene in calving
1. Rule of thumb: assist after 2-3 hours of labor, or 30 minutes of no progress. Statistically, early intervention is more successful than waiting until the cow is exhausted and the calf is stressed. Calves that experience calving difficulty are less healthy. Furthermore, they will take longer to stand and nurse if they have a difficult birth. Calves require colostrum within 4 hours of birth. The sooner they nurse, the more antibodies they absorb from their mother’s colostrum. Delayed nursing due to prolonged delivery may increase illness do to respiratory disease and scours. Calves that are sick early in life often have lower weaning weights and poorer performance once on feed. Cows and heifers that experience calving difficulty will probably not rebreed as rapidly. Giving the cow more time to see if she can do it on her own, while perhaps successful in delivery of the calf, may result in a weakened calf and a cow that is delayed in rebreeding. This may even result in culling of the animal if you limit yourself to a 45-60 day breeding season and she can’t get bred in this time period.
2. Cleanliness is mandatory. Wash and disinfect your arms, equipment and the perineal area of the cow.
3. Do not use liquid soap as a lubricant. It breaks down the natural lubricant of the cow and can irritate the lining of the birth canal. Standard obstetrical lubricants, unused cooking oil, mineral oil or Vaseline are all usable lubricants, although veterinary lubricants are far easier to clean up than the other oil based lubes.
4. The cow needs a comfortable calving area, about 12 square feet, under cover, well lit and well bedded.It is not recommended to put the cow in a squeeze chute, as her inclination will be to lie down during assisted delivery, and she could get stuck in the chute. It may be necessary to put her in the chute to get a halter on her so that her head is tied when you attempt to assist her.
5. Assess the situation
Has the cervix dilated? If you can pass your hand along the vaginal wall into the uterus. You should feel no ridges of tissue; it should all be smooth and continuous. If you feel a ridge of tissue (not the boney pelvis) the cervix is not completely dilated, and pulling a calf at this stage can damage the cow and the calf.
Is the second water sac broken? If the water sac has broken, it is important to make good progress to delivery. If it is broken, you should feel a wet slimy calf directly with your hands, instead of the calf through a tough membrane that slips all over the calf. It is not recommended that you break the water sac, as it could stimulate early respiration that may drown the calf if its head is not out of the vulva.
Is the calf in a normal position for delivery? The two front feet should be right side up coming out of the vulva, with the calf’s head between and on top of the legs (with the cow standing). If this is not the case, determine if you have the expertise to correct the situation. If not, call a veterinarian.
Will the calf pass through the pelvis? Forcing a large calf through a small pelvic opening can result in injury or death to either or both the cow and calf. If one person can pull the first leg outside the vulva as far as the width of one hand above the pastern and while holding the first leg in this position, if one person can pull the second foot equally far outside the vulva, then there should be sufficient room to deliver the calf. This is because at these distances, both shoulders of the calf will have passed the bony entrance of the pelvis. The circumference of the calf is greatest at the points of the shoulders. If the head and feet are still inside the birth canal, a veterinarian can still deliver a live calf via caesarian section.
OB chains should be attached below the dewclaws and above the hooves, with a single loop, and the large link on the dorsal (top) surface of the pastern.
Pull alternately on each leg to “walk” the shoulders out. At this point, traction is applied straight back, and always applied with gradually increasing pressure.
Once the head and shoulders are free, rotate the calf 90 degrees to aid in passage of the hips through the pelvis. Apply traction downwards, with gradually increasing pressure. If the calf becomes hip locked, the umbilical cord can become pinched off. Make sure the calf is breathing and call for a veterinarian.
6. All posterior presentations (rear feet first) are an emergency. The feet will appear to be upside down. While the cow may deliver the calf. without assistance, once the hips of the calf pass the pelvic rim, the umbilical cord is pinched off. The calf is deprived of the oxygen in its mother’s blood, and its head is still within the uterus, where it will not breathe. Death will ensue rapidly unless the calf is delivered immediately. Again chains are looped around each foot below the dewclaws with the large link at the front of the foot, which will now be the underside of what is showing, so that the pull comes off the actual front of the foot. If it is possible for two people to pull both hocks on a rotated fetus far enough for the hocks to appear at the lips of the vulva , then it should be possible to deliver the calf through the vagina. Rotating the calf a quarter turn will and alternating traction between the feet will assist in delivery.
Two reasonably strong people should have all the strength necessary to vaginally deliver the calf. If they cannot pull the calf, it will probably be necessary to perform a c-section or a fetotomy (removal of the fetus in pieces.) A calf jack or calf puller should only be used by someone familiar with its operation. The calf puller can exert tremendous pressure, and used incorrectly, can result in serious damage to the calf and cow.
7. The calf puller is designed to save the strength of the operator. It was never intended to stretch an oversize calf through a keyhole.
8. If you are assisting a cow and you have made no progress in 30 minutes, call a veterinarian.