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Intervention Can Save Calves
More than 50 percent of reported calf death losses are associated with
calving
difficulty, or dystocia. With timely intervention, 70 percent of those
calves might be saved
By R. Dan
Posey, DVM, DAVBP
As calving approaches, a progression of
events leads to the normal delivery of a calf. Approximately two weeks
before the onset of labor, the dam’s udder begins to fill. Her vulva
starts to relax and enlarge. Sometimes a mucous discharge can be seen.
The tailhead and vulvar area relax 12 to 24 hours before labor and about
12 hours before labor the cow becomes elusive and separates from the
herd.
There are three stages in normal labor. In
the first stage, uterine contractions push the calf up into the birth
canal and cause cervical dilation. In the second stage, membranes
rupture when the calf is pushed through the birth canal. Uterine
contractions increase and propel a normally positioned calf through the
canal and onto the ground. The third stage is after the calf is
delivered — the fetal membranes are passed out and the cervix closes.
Calving difficulties
There are four possible reasons things don’t go right during labor —
incompatibility of calf and pelvic size; wrong or faulty positioning; an
abnormal fetus; and uterine problems.
Calving difficulty in heifers is most
often linked to the incompatibility of calf and pelvic size. This is
also the most common cause of dystocia in all cattle.
The calf may be normally sized, but the
heifer’s pelvis may be undersized. Pelvic size increases with maturity,
so a good heifer development program, or purchasing properly developed
heifers, is imperative to decrease calving difficulties. Selecting “easy
calving” bulls is proven to reduce dystocia in first-calf heifers.
Calves in the wrong position, or
malpositioned, can occur in cattle of any age. The normal presentation
of a calf at birth is the “prayer” position. The calf’s head should rest
on its extended front legs.
A calf can be delivered backward if the
hind legs are extended into the birth canal. It’s unusual to
successfully deliver a calf in other abnormal positions. Obstetrical
intervention is usually needed to save the life of a calf in the wrong
position.
Abnormal fetuses, or deformities such as
conjoined twins, head, leg or spinal distortions, can cause dystocia.
Most of these calving episodes need veterinary intervention.
Uterine problems also can result in
dystocia. If the uterus is unable to contract normally due to hormonal
or mineral imbalances or muscle fatigue, there may be problems. Other
problems can include inadequate cervical dilation or abnormalities in
other portions of the birth canal.
When do you intervene?
Consider this rule of thumb: The interruption of the normal progression
of labor at any stage is good enough reason to intervene. For example, a
cow in first-stage labor for more than eight hours needs intervention.
Intervene in the second stage of labor if:
• The water sac is visible for two hours with no straining
• The cow strains to deliver with no progression for 30 minutes
• The heifer strains to deliver with no progres- sion for 60 minutes
• The dam or calf shows signs of distress, such as calf with swollen
tongue or cow bleeding from rectum
• Abnormal calf position, such as only one leg present at vulvar opening
or two front feet with no head.
Once you decide to intervene, decide if
you need help from your veterinarian.
Pull one leg at a time and only when the
dam is straining. With a normally positioned calf, home delivery can be
attempted if both of the calf’s fetlocks can be pulled a hand’s width
past the vulva. This indicates both shoulders have entered the birth
canal. Don’t use any more force than two men could exert when pulling
the calf.
If you attempt to deliver a calf,
remember:
• Good restraint is necessary
• Be clean, gentle and use lots of lubrication
• Apply obstetrical chains with loops both above and below the fetlock
• Don’t pull unless three things are in the birth canal — either two
front feet and a head or two hind feet and a tail
• Never use trucks or tractors for pulling
• If you are unable to deliver the calf within 20 to 30 minutes, call
your veterinarian
• Do a post-delivery assessment and call your veterinarian immediately
if there are tears or excessive bleeding.
Post-delivery assessment
Normal calves start breathing within 30 seconds of delivery and raise
their heads within a few minutes. They can stand within 10 minutes and
usually suckle within two hours. “Straw tickling” up the nose stimulates
a sneezing reflex, which helps clear mucus from the mouth and upper
respiratory passages. Never hang calves by their back legs. Dip the
navel cord in tincture of iodine. Make sure the calf gets adequate
colostrum as soon as possible after delivery.
Encourage the cow to stand as soon as
possible. If she is unable to stand, make sure she is sitting up
comfortably. When complications arise, call your veterinarian for advice
early.
R. Dan Posey, DVM, DAVBP, is clinical assistant professor in the College
of Veterinary Medicine at Texas A&M University, College Station.
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