These pieces of information are easy to obtain, but they need to be examined and used to review. The only thing producers can't collect by themselves is the pregnancy data on cows. Producers should not skip hiring a veterinarian to pregnancy check cows. Knowing which cows became pregnant and when they are due to calve is important to making management decisions. In addition, preg check time is a good opportunity to visit with the veterinarian about your herd health management plan, changes in vaccines and other health products, cows with chronic conditions, and cow culling.
Number and percentage of calves weaned gives producers an indicator of the herd's past reproductive performance and indicates places for improvement. To calculate the percentage of calves weaned, the number of calves weaned should be divided by the number of cows in the herd at the beginning of the breeding season about 18 months ago. Percentage of calves weaned will give producers information on overall reproductive status of the herd. Good herds will average a weaning percentage of 83-89 percent of all cows that were present at the time of breeding. Better herds will average 90-95 percent. Remember this is a percentage of all cows present 18 months before.
Three problem areas
Herds with a low percentage of calves weaned (less than 83 percent) indicate problems in one of three areas. First (and most often), it may be a function of too many open cows. This would indicate a general fertility problem with either the bull or cows. The cause of infertility may be nutritional, physiological, genetic or disease-based. Second, it could be the result of too many calves dying within 24 hours of birth. High calf losses at calving time are usually caused by dystocia (calving difficulty), weather conditions or lack of assistance at birth. Finally, high calf losses between birth and weaning indicate a non-reproductive problem. Usually, these losses result from disease problems such as scours or pneumonia.
Timely marketing of open cows can greatly impact an operation's profitability. Open cows should be managed to be sold as fleshy cows during peak cull cow market times of December, January or July.
Body condition scoring cows at weaning allows producers to sort cows into management groups for feeding. Cows need to be in BCS 5 to 6 by calving time. Thin cows (less than BCS 4) and young cows should be sorted into a separate group from mature cows in good condition. The "thin/young" group should be fed to gain weight by calving time while cows in good condition should be managed to maintain condition.
Immediately after weaning is the best time to put body condition on cows. The cow's nutrient requirements are low and weather is favorable for putting on weight. Fall calving herds can graze hay fields or use rotational grazing to improve forage availability for cows. Spring calving herds should be using stockpiled fescue to put weight on dry pregnant cows.
Reproductive management is the key to a successful cow/calf operation. Analysis of where an operations program is at weaning gives producers enough time to make changes or improvements before the next calving and breeding seasons.
Jerry Little is Boyle County Extension agent for agriculture/natural resources.