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A Competitive and Unpredictable Feeding Environment Disrupts Feeding and Social Behavior of Pre-partum Dairy Cows
Management during the pre-calving period can alter the behavior of dairy cows. The objective was to determine the effect of a competitive and unpredictable feeding environment on feeding and social behavior of pre-partum dairy cows. Sixty-four animals were randomly assigned to treatment (n = 4 animals x 8 groups) or control groups (n = 4 animals x 8 groups). Each group consisted of 3 multiparous cows and 1 primiparous heifer. During a 1 wk baseline period (5 wk before calving) all groups had free access to 4 Insentec feed bins. From 4 wk before calving until calving, control cows were given ad libitum access to 6 feed bins. For treatment groups, 4 non-experimental cows were added to the pen. After 2 wk, treatment groups were moved into a pen with 4 new cows. Throughout the treatment period morning feeding times were delayed at random 0, 1 or 2 h on alternate days. Cows were excluded if they calved with twins, aborted or calved > 2 wk early. Feeding behavior (intake, feeding time, rate of intake, visits to the feed bins and intake per visit) and social behavior (total, initiated and received replacements at the feed bins) were collected electronically. Group was considered the experimental unit. Data were analyzed using a mixed model in SAS including baseline data and parity as covariates, week as a repeated measure (wk 3, 2, and 1 before calving) treatment as the main effect, a week*treatment interaction and group as a random effect. Treatment did not affect feed intake, but decreased time spent feeding (3.9 vs 4.2 ± 0.1 h/d; P=0.003) and increased feeding rate (82 vs 63 ± 2 g/min; P<0.001). Treatment groups visited the feeder less often compared to controls (47 vs 87 ± 3 visits/d; P<0.001), and consumed more feed during each visit (0.39 vs 0.19 ± 0.01 kgDM/visit; P<0.001). Treatment groups were involved in more competitive replacements at the feeder (30 vs 22 ± 1 no./d; P<0.001), both initiated (15 vs 10 ± 1 no./d; P<0.001) and received (15 vs 12 ± 1 no./d; P<0.001) compared to control cows. In summary, a competitive and unpredictable feeding environment disrupts feeding and social behavior of dairy cows; these effects may be especially problematic for pre-partum cows that are particularly susceptible to disease.
Keywords: Close-up, stress, parturition