Maternal isolation behavior of Holstein dairy cows kept indoors1

The aim of this study was to determine if, and under what conditions, indoor-housed dairy cows would seek a shelter to calve. Seventy-two Holstein dairy cows were paired by expected calving date and moved into a maternity pen that contained an open area with no cover and a sheltered area that was covered on all sides except for the ceiling and an entrance where cows could freely enter or exit. Once the first cow of a pair calved ("pair-housed"), she was removed; the second cow remained in the pen until calving ("single-housed"). For both pair- and single-housed cows, location and time of calving was determined by video. For single-housed cows, use of each area in the 12 h before calving was measured, and for pair-housed cows, distance from partner during the 12 h before calving was measured. Single-housed cows were more likely to calve in the shelter but only when calving occurred during the day (P = 0.03). Pair-housed cows were more likely to calve in the open area, regardless of time of day (P = 0.02). Beginning about 8 h before calving, single-housed cows that calved in the shelter increased their use of the shelter, and pair-housed cows spent more time away from their partners (P < 0.001 and P = 0.01, respectively). These results suggest that indoor-housed dairy cows prefer a shelter during calving but only when they were housed individually and when calving during the daytime.