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.
For more on this topic, read these articles on BovineVetOnline.com