The Calving Season Management
Livestock Update, March 2008
Dr. W. Dee Whittier,
Extension Veterinarian, Cattle
VA-MD Regional College of Veterinary Medicine, VA Tech
With many Virginia beef cows set to calve in the next few months, watching for and helping cows that have trouble becomes a special concern. Time spent watching for calving and appropriate help pays dividends in more live calves and healthier cows after calving.
How often should cows be observed? This question will have to be answered for each operation. Of course, heifers will merit more attention than cows. In the 1993 Cow/Calf Health and Productivity Audit producers reported assisting 18% of first calvers at birth but only 2.5% of cows.
The number of times that females expected to calve soon were observed was also surveyed in this study. Table 1 shows the results of this item.
Table 1. Percent of operations by number of times females were observed over a 24-hour period. From Cow/Calf Health and Productivity Audit, 1993. USDA.
One important question becomes the amount of time cows that are starting to calve should be given before examination. These cows are in the first stage of labor during which the cervix dilates and the calf is positioned for delivery. Cows in the first stage of labor tend to isolate themselves, stop eating and chewing their cud and get up and down. This stage of labor can take from 2 to 8 hours. One rule of thumb for the time to examine these females is to examine cows found by themselves in the morning before noon and cows found in the evening before going to bed. Cows with true breech presentations (backwards with feet down) or uterine torsions never strongly push so waiting for this sign can have disastrous results.
Once cows start into active labor then the time given before assistance is also an important decision. In research done in Montana many years ago researchers reported higher calf survival, higher dam survival and better future reproductive performance if intervention was earlier. In Figure 1 below, results from the Cow/Calf Health and Productivity Audit are depicted. Interestingly, over 10% of producers still allowed females to labor more than 5 hours before assisting. Certainly the ease with which females can be gotten up will greatly affect the decision to help a cow with apparent difficulty in calving.
Figure 1. Percent of operations by amount of time females were allowed to labor before intervention. From Cow/Calf Health and Productivity Audit, 1993. USDA.
Many producers today choose to intervene by themselves initially. One recommendation is to limit active intervention to thirty minutes before enlisting the help of a veterinarian. After one-half hour of assistance without substantial progress many unfavorable things begin to happen. If the calf is alive fetal stress may result in death, cows’ tissues swell, become dry and infected, operator frustration and exhaustion often become a factor. Veterinarians have training and tools that may allow them to succeed when operator efforts have failed.
Economic analyses consistently indicate that the percent of cows in an operation weaning calves is a more important predictor of profitability than most any other figure. To achieve a high percentage of calves weaned per cow exposed, not only does fertility need to be high but calf death losses must be low. Nearly all studies show that the greatest losses occur during the birth process. Appropriate calving season management can help the profitability of nearly every cow/calf operation in Virginia.