Short communication: Pair housing dairy calves in modified calf hutches

The objective of this study was to test if body weight (BW) and starter intake increased and reaction to novelty decreased for preweaning Holstein heifer calves pair housed in modified hutches (n = 8 pairs) versus individually housed in a single hutch (n = 14 calves). Calves were alternately assigned to housing treatment at d 5 of age. Cross sucking was recorded in 5-min scans for 30 min after milk feeding once per week over 14 wk. Calf health and BW were measured weekly from birth until approximately 88 d. When calves were 60 d old they underwent a food neophobia test where they were exposed to a novel feed for the first time. Cross sucking was observed only 5 times (in 4 different pairs) over the entire milk-feeding period. Pair-housed calves ate more starter than individually housed calves [0.89 (0.72-1.08) vs. 0.48 (0.42-0.56) kg/d; median and confidence interval], these calves also consumed 2.6 times more novel feed in the neophobia test (150 +/- 27 vs. 58 +/- 20 g/30 min). We observed no effect of treatment on BW. We concluded that social housing in modified hutches promotes solid feed intake and decreases fearfulness in dairy calves.