Summer-born calves wintered on cornstalks have lighter weaning weights than those wintered in a drylot, but catch up in the feedlot, in a University of Nebraska Study.
In a previous article, we outlined results from Nebraska research comparing performance of cow-calf pairs wintered on drylot rations versus those on cornstalks. Results of that three-year trial showed drylot calves gained more weight, but the advantage was offset by higher input costs compared to crop-residue grazing.
After weaning both groups of calves in April, the researchers followed them through finishing to compare performance and also to compare two post-weaning management strategies, with half of the calves maintained on a growing diet for 76 days prior to finishing and half moving directly to finishing.
The calves wintered on cornstalks entered the post-weaning phase weighing, on average, 56 pounds less than those wintered in a drylot. However, the cornstalk calves compensated with greater intake, higher average daily gains and better feed efficiency. At slaughter, the weight advantage for the drylot calves averaged just 16 pounds on a live basis and 10 pounds on a carcass basis. Carcass characteristics for the two groups were similar.
Among the two post-weaning treatment groups, the calves that spent 76 days in a growing program took longer to finish, with their total time on feed at 253 days versus 193 days for those that went directly to a finishing program. With both groups slaughtered at similar backfat endpoints, the calves that started on the growing diet finished 71 pounds heavier on a live basis and 45 pounds heavier on a carcass basis, compared with those that went directly to a finishing ration. The researchers theorize the growing phase allowed more skeletal growth, which helped those calves finish at heavier weights.
The researchers concluded that the pre-weaning management systems in this trial – pre-weaning wintering on cornstalks versus drylot – did not significantly affect outcomes in the feedlot. Post-weaning management however, in this case finishing versus growing then finishing, did produce different results, with a growing period resulting in later slaughter date but facilitating heavier finished weights.
Read the full report in the 2018 Beef Cattle Reports from the University of Nebraska.