COW/CALF CORNER
Helping the cow and the calf during, and after Stage 2 of calving
Glenn Selk, Oklahoma State University Emeritus Extension Animal Scientist
An issue facing the rancher at calving time, is the amount of time heifers or cows are allowed to be in labor before assistance is given. Formerly, traditional text books, fact sheets and magazine articles stated that “Stage 2” of labor lasted from 2 to 4 hours. “Stage 2” is defined as that portion of the birthing process from the first appearance of the water bag until the baby calf is delivered. Research data from Oklahoma State University and the USDA experiment station at Miles City, Montana clearly show that Stage II is much shorter, lasting approximately 60 minutes in first calf heifers, and 30 minutes or less in mature cows.
Table 1. Research Results of Length of Stage II of Parturition
Source | No. of Animals | Length of Stage 2 |
USDA (Doornbos, et al.1984. JAS:59:1) | 24 mature cows | 22.5 min. |
USDA (Doornbos, et al.1984. JAS:59:1) | 32 first calf heifers | 54.1 min. |
Oklahoma State Univ. (Putnam, et al. 1985. Therio:24:385) | 32 first calf heifers | 55.0 min. |
In these studies, heifers that were in stage 2 of labor much more than one hour or cows that were in stage 2 much more than 30 minutes definitely needed assistance. Research information also shows that calves from prolonged deliveries are weaker and more disease prone, even if born alive. In addition, cows or heifers with prolonged deliveries return to heat later and are less likely to be bred for the next calf crop. Consequently a good rule of thumb: “If the heifer is not making significant progress 1 hour after the water bag or feet appear, examine the heifer to see if you can provide assistance. Mature cows should be watched for only 30 minutes before a rectal examine is conducted.” Make certain the cervix is completely dilated before pulling on the chains. If you cannot safely deliver the calf yourself at this time, call your local large animal veterinarian immediately.
Despite our best efforts at bull selection and heifer development, cows or heifers occasionally need assistance at calving time. Every baby calf has a certain degree of respiratory acidosis. Acidosis is the result of the deprivation of oxygen and the accumulation of carbon dioxide that results from the passage of the calf through the birth canal. The excess of carbon dioxide results in a build-up of lactic acid (therefore the acidosis.) In order to correct the lack of oxygen and the excess of carbon dioxide and its by-products, the healthy calf will pant vigorously shortly after birth. Some calves, however, may be sluggish and slow to begin this corrective process. Calves born after a prolonged stage 2 or calves delivered backwards (hind feet first) often are sluggish and severely acidotic.
It is imperative that the newborn calf begins to breathe as soon as possible. To stimulate the initiation of the respiratory process, a few ideas may help. First, manually clear the mouth and nasal passages of fluids and mucus. Traditionally, compromised calves were held up by their hind legs to allow fluid to drain from the airways, but now many veterinarians and animal scientists don't recommend this. Most of the fluid that drains from an upside-down calf is stomach fluid, important to health. Holding the calf by its hind legs also puts pressure on the diaphragm from abdominal organs, interfering with normal breathing. It's better to use a suction bulb to clear the airways.
Hanging the calf over a fence also is NOT a recommended method for a sluggish newborn. The weight of the calf on the fence restricts the movement of the diaphragm muscle. The fence impairs the diaphragm’s ability to contract and move. This diaphragm activity is necessary to expand the lungs to draw in air and needed oxygen.
A better method is to briskly tickle the inside of the nostrils of the calf with a straw. This will usually cause the calf to have a reflex action such as a “snort” or cough. The reflex cough or “snort” expands the lungs and allows air to enter. Expect the calf to pant rapidly for a few minutes after breathing is initiated. Panting is the natural response that increases oxygen intake and carbon dioxide release and will allow the calf to reach normal blood gas concentrations. Click on this link https://www.youtube.com/
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