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Beef Cattle Production Information |
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Beef Cattle
Calving Assistance
Assessing the need for intervention Limit the calving season to as short a period
as practical. With a short calving season it becomes more practical to observe
cows often enough to provide timely assistance. It is important to have a
calving watch so all signs can be observed and help given when needed, without
interrupting normal parturitions for unnecessary examinations. Record expected
calving dates of individuals; this is practical only with artificial
insemination or hand breeding but is very helpful in determining which cows to
watch more closely. Cattlemen should develop a competence and
confidence in determining when to intervene, in aiding deliveries, and in
assessing the need for professional assistance. A cow should be examined if she
has labored two or three hours without progress or if the calf has not been born
within two hours after appearance of a waterbag. Overzealous intervention before
the cervix is fully dilated may result in severe injury to the cow as well as
the calf. A cow can be more easily examined when she is
standing. Lying down forces her abdominal organs and the fetus into or against
the pelvic cavity. If a cow will not or cannot rise, it will help to position
her upright on her sternum and stifles with her rear legs extended behind her. The vulva and surrounding area as well as the
hands and arms of the person making the examination should be washed thoroughly
with warm water and soap. Cleanliness at all times during examination and
delivery cannot be over-emphazized. Thoroughly lubricate the arms of the
examiner and the birth canal. Lubricating gels are available commercially, or
one can be prepared by dissolving mild soap flakes in a small amount of
hot water and allowing the solution to cool. Carefully examine the birth canal to determine
if it is fully dilated and free of twisting and obstruction. Evaluate the size
of the fetus in relation to the diameter of the passage. Pull on and pinch a
foot of the calf to determine if it is alive. Examine the fetus to determine its
position and the presence of any abnormal structures. Normal birth is possible
only with the fetus in anterior or posterior presentation, right side up, with
head and limbs extended. The possibility of twins should always be considered. Determine whether the feet presented are front
or rear feet. Front limbs have two joints between the hoof and elbow, whereas
rear limbs have only one joint between the hoof and hock. A cow is more apt to
require assistance with a posterior delivery than with an anterior delivery.
Rear limbs are not as effective in initiating dilatation of the birth canal and
stimulating abdominal contractions as is the head, the tail head of the calf
tends to impact against the cows back bone, the hair of the calf lies the wrong
way, and compression of the calf's abdomen causes its rib cage to expand. With
posterior presentation, flow of blood through the navel cord is impeded early in
delivery, and the calf's head is submerged in fluid. Once the hips enter the
birth canal, delivery must be rapid for a live birth. If examination reveals abnormalities of the
fetus or birth canal, failure of the tract to properly dilate, or a calf
apparently too large for safe delivery through the birth canal, professional
help should be sought at once. Provide adequate facilities and equipment for
aiding deliveries. A large well-lighted stall should be reserved as a maternity
area. It should be sanitized and well bedded each time it is used. Obstetrical chains are preferred to other
traction aids because they are more easily disinfected, and handles are
available that may be quickly attached anywhere along their length. Two Chinch
chains, one 60-inch chain, and two handles are desirable. Equipment should be
cleaned and boiled in mineral oil after use to prevent spread of disease and
rusting. Cotton sash cord works well but should be discarded after use. A good
mechanical calf puller is needed, not for the amount of pressure it will exert,
but for the directions of traction that can be achieved. Other methods of
applying traction, such as block and tackle or fence stretchers, apply no
opposing force to stabilize the cow and allow pulling parallel to her body only.
~ Traction should be applied cautiously until the
vagina and vulva are fully dilated. Tearing the cervix or vagina may result in
sterility or death of the cow. The whole purpose of the procedure is to deliver
a healthy calf and prevent injury to the cow. If forced extraction is required, chains should
be placed carefully on the extremities. If fetal membranes interfere, they
should be torn away. Place the noose of the chain above the fetlock and a
half-hitch around the pastern. This reduces the risk of fracturing a bone or
pulling off toenails. When one or both front or rear limbs or the
head is retained in the uterus, manipulation of the fetus is required before
traction is applied. Fetal parts must be guarded with the hand to avoid tearing
the uterus. Some manipulations can be made with one hand; others require
opposing force. Opposing force is accomplished by placing a loop of chain on a
foot or the lower jaw and pulling on the chain with one hand while repelling the
poll, shoulder, elbow, hip, or hock with the other hand. Care must be taken that
the teeth or toes do not tear the uterus. To apply traction to the head, pass the chain
loop over the poll behind the ears and through the mouth. This causes the mouth
to open, so care must be taken that the calf's teeth don't lacerate the birth
canal. Limit head traction on a live calf to relieving impaction of the head and
extending the neck; pulling on the head to move the body may cause injury to the
calf's spinal cord. If the muzzle appears before one or both feet,
the elbow(s) may be impacted against the pelvic brim or the forelimb(s) may be
retained in the uterus. An impacted elbow can usually be corrected by moderate
traction on the foot, however, it may be necessary to apply opposing force to
the head to make room for correction. If one or both forelegs are retained in
the uterus, it is often necessary to push the head back through the pelvic inlet
to correct the problem. If it is very difficult to get the head and both
forelegs into the birth canal at the same time, mechanical traction should not
be applied. Either the positioning is faulty or the passage is too small to
accomodate the calf. Shoulder lock occurs when the calf's shoulders
become impacted at the pelvic inlet. To relieve a shoulder lock, apply moderate
traction to the head and alternately apply traction to the forelimbs so the
shoulders are "walked" through the bony pelvis one at a time. If the shoulder
lock is severe, a caesarian section should be considered; a shoulder lock
relieved with difficulty may be followed by a worse hiplock. Hip lock (calf's hips impacted at pelvic-inlet)
should be dealt with promptly. The calf usually doesn't survive long in hip
lock, and the cow may become paralyzed due to excessive pressure on the nerves
to her hind limbs. Direction of traction is very important. If a hip lock
develops with the cow standing, fasten the forelimbs of the calf together with a
short chain, step up in the stirrup formed by the chain, and swing your weight
forward between the hind feet of the cow. Hip lock can often be corrected in a
cow lying down by repelling the fetus a little, then applying traction over the
uppermost rear leg of the cow toward her shoulder. A chain can be placed around
the abdomen of the calf and traction applied downward. A 45° rotation of the
calf will aid in relieving a hip lock because the vertical diameter of the
pelvis is greater than the horizontal diameter. A calf presented backward must be delivered
backward. It is not possible to turn a calf around in a cow. Lubricate the fetus
and birth canal before delivery is attempted. Place chains above the calf's
hocks and attach the calf puller before applying traction. Once the hips enter
the birth canal, traction should be rapid and uninterrupted. Alternating
traction on the rear legs and rotating the fetus 45° may help. If it is very
difficult to get the hips through the pelvic inlet, a caesarian section may be
required. This decision should be made before the hips are forced into the birth
canal and the life of the calf jeopardized. If a calf is presented butt first (breech), the
cow often does not enter second-stage labor as point pressure is not exerted
within her pelvis to stimulate abdominal contractions. The tip of the calf's
tail may be protruding through the vulva or lying in the vagina. The subtle
signs of first-stage parturition often go unrecognized, and the cow appears sick
or discharges a putrid fluid two or three days later. A breech presentation may be relatively easy or
very difficult to deal with. Important variables include how soon the problem is
recognized, whether or not the cow will stand during manipulation of the fetus,
the amount of abdominal space for manipulation, how rigidly the calf's hocks are
extended, and how hard the cow strains. The calf's hips must be repelled forward,
upward, and toward one flank, the hocks flexed, and the feet extended backward
into and through the birth canal. It is very helpful if the cow will stand
during manipulation of the fetus. The calf should be repelled between labor
pains, and care must be taken not to tear the uterus by pushing too hard on the
calf. If manipulation is difficult, epidural anesthesia (a local anesthetic
injected into the cow's spinal canal) should be administered to stop straining. Efforts by the cattleman to assist delivery
should be limited to thirty minutes, and should not exceed his technical
capabilities. To delay calling a veterinarian when his help is needed can result
in unnecessary injury or death of the cow as well as the calf. Provide adequate aftercare for the calf and its
mother. Two emergencies may exist upon completion of the delivery: the calf may
fail to breathe, and the cow may attempt to prolapse her uterus. The calf can be
stimulated to breathe by inserting a straw 2 or 3 inches into the nostril, by
brisk massage, and by slapping the chest. Excess mucus should be cleared from
the airway, and the head kept lower than the chest until the calf is breathing.
Brisk massage with a rough cloth, such as burlap, will also stimulate
circulation. Commercial aspirator-respirators are available and are helpful in
aspirating mucus and administering oxygen. Directions provided by the
manufacturer should be followed. The cow should be encouraged to get up and move
around so her uterus will fall into the abdomen and labor will cease. Straining
can sometimes be interrupted by vigorously gripping the cow's spine at the
middle of her back. Examine the reproductive tract for tears and the presence of
another calf. After emergencies are averted, saturate the
calf's navel with an iodine solution. Within fifteen minutes after birth, the
calf should nurse the cow or be given a quart of colostrum by nipple or
esophageal feeder. Inject cow and calf with broad spectrum antibiotics. Avoid
putting boluses, especially those containing urea, in the uterus. They are
irritating to uterine mucosa and may result in delayed conception. If the
placenta is retained, continue to administer broad-spectrum antibiotics daily
until it is passed. If the cow goes off feed or in any other way appears sick,
consult a veterinarian.
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