Comparing weaning methods in dairy calves with different dam contact levels

Abstract

Allowing the dam to rear her calf is an alternative practice in the dairy industry where cow and calf may gain welfare benefits from performing natural and highly motivated behaviors. However, this system has been linked to an increased separation and weaning response. Reducing the daily dam-calf-contact time may be a way to prepare the calf for weaning and separation. The first aim of the present study was to investigate the effect of 8 weeks of half-day dam-calf-contact on calves' response to weaning and separation, compared with calves reared with whole-day dam-calf-contact and an artificially reared, group-housed control with unrestricted access to milk for 20 min twice daily. Weaning off milk and separation from the dam can be viewed as 2 independent stressors. By introducing each stressor separately, it may be possible to reduce the overall behavioral response. The second aim of the present study was to investigate the effect of one-week fence-line weaning before permanent separation. The study was conducted with a 3x2 factorial design with dam-contact treatments: "Whole-day," "Half-day" and "Control" and weaning treatments "Simultaneous" and "Stepwise." Whole-day calves were separated twice daily from their dams during milking while Half-day calves were separated daily from the afternoon milking and until next morning milking. Simultaneous weaning and separation were done in wk 9, while Stepwise weaning and separation started in wk 8 with calves being fence-line weaned before permanent separation in wk 9. Data were collected on 69 dairy calves in wk 8 and wk 9, and data were summarized over the 2 weeks for analysis. Stepwise weaning and separation reduced the number of high-pitched vocalizations and activity of dam-reared dairy calves, while having little impact on control calves. There was no difference between Whole-day and Half-day calves in their response to separation, but as expected, dam-reared calves reacted more strongly than the control group. This was also reflected in the average daily BW gain the week after weaning, with Control calves having a higher average daily gains than Whole-day, while Half-day calves were intermediate. However, the behavioral response did not fully wane within the observation period (0-48 h of interventions). In conclusion, one-week fence-line weaning reduced the summed weaning and separation response in dam-reared calves. However, no difference between half-day dam-calf contact and whole-day dam-contact was detected as regards the behavioral response to weaning and separation.