The summer of 2012 has again diminished pastures and harvested forages. Those producers that still own spring calving cows that are nursing calves should consider the option of early weaning the calves to give the cows the best opportunity to maintain some body condition going into winter.
South Dakota State scientists examined this scenario (using mature cows) by comparing the effect of weaning date on performance of the beef cows. They weaned half of the cows at the time of the first real cool spell (September 14). The other half of the cows had their calves weaned at a traditional time (October 23).
The scientists then monitored body condition and rebreeding performance of the cows. Note that this study included two different nutritional levels: 1) A low group to mimic an early winter or a dry summer; 2) A moderate group to mimic more ideal summer and early winter seasons. Only the data for those cows exposed to the low nutritional group are presented here. They more nearly reflect what may happen for young cows in a drought than will the moderately fed cows.
This data indicates that the 40 days earlier weaning allow the cows to maintain more body condition score (0.5 BCS) going into winter. More of the early weaned cows were cycling at the start of the breeding season, conceived early in the breeding season and should wean heavier older calves the following year.
In addition a small amount of high protein supplement (i.e. cottonseed meal or soybean meal) will enhance the cow's ability to utilize the declining quality of the late summer forage and/or low quality grass hay. Therefore allowing more body condition to remain on the young cows before frost arrives. This combination of management techniques should be a cost effective way to slow the decline in re-breeding rates of drought-stressed, spring calving cows.
Taking care of the early-weaned calves becomes another challenge that must be met, if the calves are not sold “off of the cow”. The early-weaned calves (if properly vaccinated) will be ready for any of the special value-added calf sales that require 45 day weaned-calves. Fenceline weaning would be a recommended practice for the weaning process of these light calves. Remember, if you wean in this hot weather, you MUST have ample supplies of fresh water on both sides of the fence.
Feeding programs for light, early-weaned calves should be carefully planned and delivered. Suggested rations for these calves can be found in the Oklahoma State University Fact Sheet ANSI 3031: “Nutrition and Management Considerations for Preconditioning Home Raised Beef Calves .
Source: Glenn Selk, Oklahoma State University Emeritus Extension Animal Scientist