By David Cantrell
OSU Extension Educator
With weaning time quickly approaching for fall calving cows, here is an interesting study conducted by Oklahoma State University animal scientists.
The scientists evaluated weaning dates of 158 Angus fall-calving cows over a four-year period. Cows were allowed to nurse their calves for about 210 days (April Weaning) or 300 days (July Weaning). All cows calved in September or October and were weaned in mid-April (April Wean) or mid-July (July Wean).
April-weaned young cows had greater re-breeding percentages (98.4 percent versus 89.3 percent) than July-weaned young cows. However, there was no advantage in the re-breeding performance of April-weaned mature cows compared to July-weaned mature cows (90.2 percent versus 96.7 percent). April–weaned cows were heavier and fleshier than July-weaned cows.
Calves weaned in July were 90 days older and 204 pounds heavier (642 lb. versus 438 lb.) when weaned than were April-weaned calves. The April-weaned calves were allowed to graze native pasture after weaning and weighed 607 pounds in mid-July.
For most years, it appears more advantageous to delay weaning calves born to cows 4 years or older to July while maintaining April weaning for cows 3 years of age or younger.
On-going drought conditions in some areas very well may suggest the earlier weaning date could be considered for all ages of cows.
For more information on weaning calves, contact your local OSU Extension Office
David Cantrell is the agriculture Extension educator for Pittsburg County. Contact him at 918-423-4120.