“Disinfect obstetric chains between uses by boiling in water for 20 minutes to prevent the spread of disease. After boiling, wrap the chains in clean cloth or store in clean plastic bags until further use.
“Now is the time to purchase medicines used in calving and place them in ranch inventory. Include 2 percent tincture of iodine for treating navels and an obstetric lubricant, in the event a cow or heifer requires help in calving. Colostrum replacement is needed in case a calf is unable to nurse after birth.”
Observation and examination
To avoid the loss of a calf during a difficult birth, you must be able to recognize the three stages of parturition (calving) that are shown in Table 1.
Also shown in Table 1 is the normal duration of each stage, the events by which the stage is identified and triggers for when you should intervene and help the cow or heifer complete the birth of her calf.
“Heifers should be observed three to four times a day for several days before calving begins,” recommends Faries. “A heifer or cow should be observed at hourly intervals once fetal parts protrude through the vulva to the outside.”
“If labor has continued for two or three hours with no progress, further decisions need to be based upon a pelvic examination,” Dr. John Beverly wrote in a Texas AgriLife Extension Service bulletin. “A careful examination of the cow is possibly the most critical step in assisted deliveries.
Before the examination, remember that sanitation is of utmost importance to prevent introduction of infectious organisms into the reproductive tract.
Your arm should be well-lubricated to facilitate the examination and to minimize trauma to delicate reproductive tissues.”
“Examine the cervix for dilation,” explained Beverly. “If the hand is inserted into the vagina, and it is found that the cervix will only admit two to three fingers, it is probably not dilated.
When the cervix is dilated completely, it is approximately 6 to 7 inches wide. At this time, the cervix and the vagina become a continuous canal and in most instances are tightly engaged by the stretched fetal membranes.”
Next check for life signs in the unborn calf, which will determine urgency and type of needed assistance.
If the calf is alive, pulling or pinching the foot causes movement of the leg or placing your fingers in the calf’s mouth elicits sucking or movement of the tongue. Absence of the vital signs, sloughing of the hair or foul odors may indicate the calf is dead.
“The third step is to determine the presentation, position and posture of the calf,” Beverly said. “Presentation is the relative direction of delivery.
The calf may be presented frontwards, backwards or crosswise to the pelvic opening. Normal presentation of the calf is frontwards. Although a calf can be pulled in a backwards presentation, there is some danger.”
Position describes how the calf is lying. The calf may be upside down, right side up or may have its back to either side of the cow’s pelvic canal.
The normal position of the calf is back side up. Never pull a calf in any other position because the chances of killing both the cow and calf are great.
Posture indicates the location of the legs, head and neck. The correct posture of the fetus is with both front legs outstretched in the birth canal and with the head and neck extended along the legs. Correct any deviation from this posture before the calf is extracted.
“Determining the relative size of the calf and birth canal is the final step of the examination,” wrote Beverly.
“Forcing a large calf through a small pelvic opening almost invariably results in death of the calf as well as injury, paralysis or even death of the cow.
If it is fairly certain the cow will have serious calving difficulties, call a veterinarian. Once the calf’s feet and head are outside the cow’s body, the veterinarian has lost the option of doing a Caesarean section.”
Parturition assistance
“To prevent gross and potentially overwhelming contamination during assisted calving, properly restrain the heifer or cow,” cautions Faries. “Restrain by using a low head tie, not a chute, to give the animal room to lie down during assisted delivery.
Thoroughly cleanse the perineum or rear portions of the animal before examining the birth canal. Liberally apply mild soap and water and thoroughly rinse the area of the tail head down to approximately 12 inches below the vulva. The width of the scrubbed area should extend laterally to include the pin bones.
The tail can be tied to the animal’s neck or elbow to keep it out of the way during assistance. The assistant’s hands and arms should be cleansed with soap, water and an antiseptic solution.”
“Delivery of the fetus is eased by the use of obstetric chains,” explains Faries. “Cotton ropes and nylon web obstetrical straps can also be used.”
“The best placement of a rope or chain on the limb of a calf is a loop above the ankle and a half-hitch below the ankle. This distributes the point of pull to reduce the potential of fracturing a fetal limb during delivery.
Place the chains or other straps directly on the skin. Placing them over the water sac covering the limbs will impede delivery.”
“Delivery should be assisted by walking the calf out,” continues Faries. “This is accomplished by alternating the pull on each leg. Pull one leg at a time with a maximum traction of 200 pounds.
Get both legs fully extended before applying more traction. Pull in an upward direction. Be sure to keep the nose in position with the ankles and continue to pull upward to deliver the calf beyond its shoulders.
Then pull downward, through an arc, to complete delivery of the calf. The maximum traction to apply to the calf with extended legs is 600 pounds.”
“After a calf has been delivered, check for a heartbeat by placing a hand on the lower chest just behind the front limbs,” recommends Faries.
“Provide an open airway for breathing using a dry paper or cloth towel to wipe excess mucus from the mouth. Stimulate respiration by placing a piece of hay or straw in the nostril to initiate a sneeze.
After the calf is breathing and relatively stable, treat the calf’s navel with 2 percent solution of iodine.”
“Also, make sure the calf drinks 1 to 2 quarts of colostrum (first milk) from the dam within the first six hours of life,” Faries continues.
“It is best when nursed, but if the calf is too weak, provide the colostrum by stomach tube. If the calf is small, divide the colostrum into two to three feedings during the first six hours.”
Faries also recommends some post-delivery care of the dam, which includes re-examining the birth canal and checking for an additional fetus.
Look at the posterior birth canal for excessive tearing or bruising that could require the attention of a veterinarian.
With proper attention and care, cows can successfully calve. 
Robert Fears is a freelance writer based in Texas.
PHOTO
Obstetric chains can ease deliveries, and should be placed directly on the calf’s ankles with a loop and half-hitch. Photo courtesy of Bunchgrass Veterinary. Dr. Wendy Meek.
