Expanding drought conditions are once again leading many cattle producers to manage for diminished pastures and a lack of harvested forages.
“Those producers who still own spring-calving cows that are nursing calves should consider the option of early weaning,” said Glenn Selk, Oklahoma State University Cooperative Extension emeritus livestock specialist. “The purpose of early weaning is to give the cows the best opportunity to maintain body condition going into winter.”
South Dakota State University scientists examined this scenario using mature cows and comparing the effect of weaning date on performance of the beef cows. They weaned half of the cows at the time of the first cool spell on Sept. 14 and weaned the other half at the more traditional time of Oct. 23. The scientists then monitored body condition and rebreeding performance of the cows.
“Be aware that this study included two different nutritional levels: A low group to mimic an early winter or a dry summer and a moderate group to mimic more ideal summer and early winter seasons,” Selk said. “The data for the low group reflects the expected performance of cows in drought conditions similar to what we have been seeing.”
The data indicate that weaning 40 days earlier allows cows to maintain a better body condition score going into winter. More of the early weaned cows should be cycling at the start of the breeding season, conceive early in the breeding season and should wean heavier, older calves the following year.
“In addition, a small amount of high protein supplement such as cottonseed meal or soybean meal will enhance the cow's ability to utilize the declining quality of the late summer forage or low-quality grass hay, thereby allowing more body condition to remain on young cows before frost arrives,” Selk said.
He added that this combination of management techniques should be a cost effective way to slow the decline in rebreeding rates of drought-stressed, spring-calving cows.
Of course, taking care of the early-weaned calves becomes another challenge that must be met, if the calves are not sold immediately.
“If properly vaccinated, the early-weaned calves will be ready for any of the special value-added calf sales that require 45-day weaned calves,” Selk said. “Fence-line weaning would be a recommended practice for these light calves. If a producer chooses to wean in hot weather, ample supplies of fresh water must be provided on both sides of the fence.”
Feeding programs for light, early-weaned calves need to be carefully planned and implemented. Suggested rations for these calves can be found in the OSU Extension Fact Sheet ANSI 3031, “Nutrition and Management Considerations for Preconditioning Home Raised Beef Calves,” available online at http://osufacts.okstate.edu  via the OSU Division of Agricultural Sciences and Natural Resources.