When raising calves on autofeeders, it’s challenging to find the “sweet spot” for milk allowances. To examine how milk allowance affects other calf behaviors, the University of Minnesota studied approximately 2,000 calves in 25 farms using autofeeders over a period of 18 months.
The researchers evaluated daily milk consumption per animal; calf drinking speed; number of calf visits to the autofeeder (rewarded and unrewarded); and estimated daily animal weight gain. Among their findings:
- Average daily milk allowance was 8.7 +/- 2.3 L/calf.
- Calves consumed an average of 87% of their milk allowance, resulting in average consumption of 7.6 L/calf/day.
- Average daily gain was 1.8 lb./day, and ranged from 1.2 to 2.5 lb./day.
- The number of daily rewarded visits (when milk was fed) ranged from 2. 5 to 6.9 visits, for an average of 4.8 visit/day. Most farms averaged between 4 and 6 visits per day.
- Unrewarded visits ranged between 0.96 and 9.9 visits per day.
- Higher milk allowance resulted in fewer unrewarded visits, while lower milk allowance resulted in more unrewarded visits.
“What this means is that the more milk we feed the calves, the more satisfied they are and they do not keep coming to the auto feeder trying to get more milk,” said Marcia Endres, professor and Extension dairy specialist at the University of Minnesota who leads the study. “They will rest more hours per day.”
Endres and her colleagues also underscored the importance of establishing a gradual weaning protocol when feeding higher amounts of milk, so that calves eat more starter feed prior to being weaned off milk completely.