The fall calving season is just around the corner for several producers around the state. While a minority of Ohio's cow-calf producers utilize fall calving as a management practice, there are several valid reasons to calve in this less traditional setting. As with just about any management practice, there are drawbacks that need to be considered as well. Producers must understand that there are unique characteristics associated with fall calving and they should be prepared for the differences when compared to a spring calving season.
I believe there are some very distinct advantages to calving in the late summer or early fall. Probably the biggest advantage for calving at this time of year is the fact that we have typically see warmer, drier conditions in the calving environment. Yes, it can be downright hot during this time, but let's not forget the challenges of calving in the first quarter of the year. We simply do not see the cold, wet, and muddy conditions that pose very real threats to calf health that we see in January through March.
The summer heat can actually provide some beneficial aspects to fall calving. While there is not a wealth of information on this subject, researchers at Oklahoma State University have examined the effects of temperatures on gestation length and birth weights of calves born in the fall. In one study, cows from were bred to calve in August or October to compare gestation length. Results from this five-year study showed that the August calving group averaged a four day shorter gestation length when compared to the October calving group. Another two-year Oklahoma State University study examined the effects of August versus October calving on birth weights. In year one, August born calves were 3.74 pounds lighter than the October born calves. In year two, the August born calves were 9.68 pounds lighter.
Dr. Glenn Selk, Oklahoma State University Emeritus Extension Animal Scientist, offers the following explanation for these results: "The reason that early fall calving cows have lighter birth weights is generally attributed to the fact that the cows are gestating in hot weather. Blood flow patterns of cattle during periods of high temperatures change in an effort to dissipate heat from the body. Blood (and the nutrients that it carries) is shunted to the outer extremities during hot weather to dissipate heat. Therefore less blood flow is sent to the inner core of the cow where the fetus is gestating. This subtle change in blood flow is commonly thought to be the reason that lighter birth weights occur to cattle that are in the last trimester of pregnancy in June, July, and August."
Regardless of the time of year for your calving season, there are some basic management practices that need to be implemented as you make preparations for the arrival of newborn calves. Avoiding calving problems starts long before calving season as proper sire selection and a balanced nutritional program can greatly minimize difficulties experienced during this hectic time. If those primary areas of concern have been addressed earlier, we can then move on to those details to help insure we achieve positive results from calving season.
Place cows and heifers close to calving in a pasture that can be easily viewed and checked often. Utilize well-drained areas that are clean and free of items hazardous to animals. Recognize the signs that calving is imminent. Restlessness, udder filling, and vaginal discharge are common indicators that calving is near. Be prepared to assist in calf delivery if reasonable progress ceases after the feet or water bag appear. The active calving stage (Complete cervix dilation, serious straining, and calf delivery) normally takes less than 90 minutes for both cows and heifers with heifers usually taking more time for delivery. Contact a veterinarian if the calf cannot be safely delivered without assistance.
Once the calf is born, make sure it is breathing properly. If the calf is having difficulty breathing, clear the nose and mouth of mucous or other obstructions. Vigorously rub the calf or tickle the calf's nostrils to help initiate breathing. If the calf has ingested birth fluids during delivery, do not hold the calf upside down in an attempt to drain fluids. This practice forces the weight of the internal organs against the lungs and may not allow the lungs to properly inflate.
Once the calf has been delivered, allow it time to stand and begin the nursing process. It is extremely important for the newborn calf to receive colostrum from its dam as soon as possible after birth. Because the newborn calf has limited immunity function, colostrum is important for building calf immunity and resistance to diseases. Calves need to receive colostrum as soon as possible after birth because as time passes, the amount of colostrum in the dam's milk declines as well as the calf's ability to absorb colostrum. There may be factors that prevent the calf from consuming colostrum from its dam. If this is the case, feed fresh colostrum from the dam, slowly thawed frozen colostrum from storage, or a manufactured colostrum substitute. Feed approximately 2 quarts for an 80 pound calf within four to six hours after birth and an additional 2 quarts again within 12 hours of birth.
There are other additional calf management practices to consider. Dip a calf's naval cord in an iodine solution or other disinfectant or drying agent spray. Move cow-calf pairs to a clean pasture as soon as possible to reduce exposure to diseases found in highly populated areas. Tag calves at birth with a unique number from an identification system that works best for your record keeping system. Record birth date, sex, birth weight, and any calving difficulties associated with each calf.
Calving season, regardless of the time of year when it occurs, is the most exciting time of year for the cow-calf producer. Months of planning and production inputs finally become reality, hopefully in the form of a live, healthy calf. The calving season you choose must work within the framework of your overall farming operation and additional time constraints. However, if I can leave you with a "sales pitch" for fall calving, consider this: Over the next few weeks, take an actual or mental picture of an average September day. Then, fast forward to the average day in the January-March time period. Which day would you choose to give youself the best chance of delivering a live, healthy calf? I know which day I would choose!
Source: John F. Grimes, Ohio State University Extension Beef Coordinator