Effects of individual housing design and size on behavior and stress indicators of special-fed Holstein veal calves.

The objectives of this study were to determine effects of housing design (calves tethered in open stalls vs untethered in individual pens) and widths of 56, 66, and 76 cm (2 x 3 factorial arrangement of treatments) on indicators of stress and behavior in special-fed veal calves. Three production cycles (groups) were used, each with 36 Holstein bull calves. Calves (n = 108) were randomly allotted to treatments upon arrival at the facility. Blood samples were collected four times (wk 4, 9, 13, and 18) during the 18-wk production cycle. Blood serum values for cortisol and alpha1-acid glycoprotein (AGP) exhibited few treatment differences. Blood leukocyte differential counts at 4 and 18 wk (segmented neutrophils [N], banded neutrophils, lymphocytes [L], basophils, and the N:L ratio) were not different (P > .05) among housing designs or widths. However, there were differences (P < .05) in monocytes and eosinophils during the 28-d period after arrival; calves in stalls 76 cm wide had the greatest percentage of both leukocytes, and calves in the 66-cm stalls had the lowest monocyte percentage. Calves were recorded on videotape during wk 4, 13.5, and 18 to determine frequencies and durations of postures and behaviors (e.g., lying, standing, chewing, tongue playing, grooming, and investigative activities). There were no consistent differences (P > .05) in postures or behaviors among calves in different housing designs or widths. Calves spent approximately 71 and 31% in lying and standing positions, with no preference for the right or left side while recumbent. There was a tendency for calves in wider stalls or pens at wk 9 and 18 to exhibit more self-grooming activities. Tongue playing and investigative and chewing activities were exhibited in all treatments, but no differences (P > .05) were observed. However, calves housed in the 56-cm pens displayed difficulty in changing from lying to a standing position and were unable to extend one or more legs while recumbent. Even though there were few differences in behavioral, physiological, growth, or anatomical traits in this study, further increases in age and(or) weight of finished calves will require a reassessment of the appropriateness of individual veal calf housing design and dimensions.