Short communication: effects of bedding quality on the lying behavior of dairy calves.

The lying behavior of adult cattle is strongly affected by characteristics of the lying surface, but no previous work has assessed the effects of lying surface for dairy calves. We evaluated how the lying behavior of dairy calves changed when calves were provided sawdust-bedded versus concrete lying surfaces, and in response to variation in dryness of the sawdust bedding. Five Holstein calves, approximately 2-wk old, were individually housed in pens with half of the lying surface bedded with kiln-dried sawdust [90% dry matter (DM)] and the other half with wet bedding varying in DM at 4 levels (74, 59, 41, and 29%) or bare concrete. All calves were tested on all 5 treatments, with treatment order assigned using a 5 × 5 Latin square. Total lying time averaged 17.2 ± 0.1 h/d and did not vary with treatment, but time lying on the wet bedding decreased from 5.3 ± 1.1 h/d at 74% DM to almost zero at 29%. Lying times on the side of the pen with dry bedding varied from 12.2 ± 1.2 h/d (when the wet bedding was 74% DM) to 16.8 ± 1.2 h/d (at 29% DM). Standing times were higher on the dry than the wet bedding (2.6 vs. 1.7 ± 0.1 h/d) but did not change across the range of bedding DM tested on the wet side. No calves ever lay down on the bare concrete. In conclusion, dairy calves showed clear preference for drier sawdust bedding and aversion to concrete lying surfaces, indicating that access to soft and dry bedding is important for growing calves.