About half of the Southern Great Plains region remains in moderate to extreme drought conditions as of late August, with the most extreme drought conditions persisting in far southwest Texas according to the National Drought Mitigation Center. Similar to the summer of 2023, the entire region has experienced intense heat through the summer months. As of this writing, within the last 45 days, 30 have exceeded 100 degrees on the Cattle Comfort Index (Oklahoma Mesonet). 

Those conditions suggest special attention should be given to vitamin A supplementation because carotene concentration, the precusor to vitamin A production, will be nonexistent in most late-harvested and stockpiled forages. We have had reports of low serum or liver vitamin A in beef cow herds and suckling calves during the past three years. 

Your veterinarian can help you with monitoring and testing for vitamin A status in your herd. Testing a few cull cows before marketing and (or) a few calves at weaning time is a good place to start. The lab we have been using charges $25 for serum samples, $32 for liver tissue samples and $100 for feed samples. 

Mary Drewnoski’s group at the University of Nebraska has recently reported about three times recommended levels (about 90,000 to 100,000 IUs per day) of vitamin A must be supplied for several months to replenish liver vitamin A stores. A series of injections can also be used to more rapidly replenish liver vitamin A. Again, consult your veterinarian for guidance.

Secondly, don’t scrimp on breeding soundness examinations (sometimes referred to as BSE) for herd sires prior to fall breeding. Because spermatogenesis is a continual process, sperm quality is reduced for about eight weeks after bulls experience heat stress.  

Spring-calving herds

Due to rapidly declining forage quality in the southern Great Plains, October represents the latest practical time to wean in most seedstock operations. Calves should be individually weighed, initial or booster vaccinations administered, and other timely herd health management steps completed. 

Individually weigh, record body condition score (BCS) and preg-check cows and bred heifers. Remember cow body weight and BCS data should be recorded within 45 days of calf weaning weight data. 

BCS is a critical component in the mature cow weight expected progeny difference (EPD). This information is increasingly important as the beef industry strives to improve cow efficiency and optimize mature cow size for different environments. Body condition scoring is a subjective measure, therefore it is important for producers to fine-tune their skills and “calibrate” their scores once in a while. One unit of body condition change should be associated with about 7.1% of the cow’s body weight change. For example, if a cow weighs 1,300 pounds (lb.) at weaning with a BCS = 6, you would expect her to lose about 92 lb. at a BCS = 5 or gain about 92 lb. at a BCS = 7. 

Cull females that are open this fall. Research has shown retained open cows average about 60% pregnancy rate going forward. Report whole-herd records to the Association office. 

Treat cows and calves for internal and external parasites. Be aware internal parasites are becoming increasingly resistant to some deworming products. Thus, it is a good idea to discuss product selection with your veterinarian. Deworming is best timed after the first killing frost, although many understandably do this at the time of weaning since the cattle are gathered. Check with your veterinarian. 

If your spring-calving cows are marginal in body condition, wean calves as early as possible. Similarly, assuming a native rangeland forage base, begin protein supplementation as early as possible. These two management steps should allow cows to gain about one full BCS before the first of the year.  

Fall-calving herds

Closely monitor late-calving heifers as the frequency of calving difficulty may be higher in heifers that have experienced long gestation periods.  
Work with your veterinarian to develop or review your branding-time herd health plan and purchase products needed to execute the protocol. 
Prepare for the breeding season by purchasing semen and other breeding supplies, testing your breeding equipment and getting synchronization protocol steps on the calendar. 

With intense summer heat, it is important to conduct breeding soundness evaluations on herd bulls prior to the fall breeding season.  

If possible, ask to see the dams (and their records) of bulls you are interested in purchasing, whether for use in natural matings or artificial insemination (AI). Selection for udder quality, foot structure, docility and a long history of reproductive success begins with bull and semen purchases. EPDs are available for foot structure, docility and heifer pregnancy.