Performance and health status in preweaning semi-indoor holstein calves wearing calf jackets during winter months.

The purpose of this study was to investigate whether jacket wearing by semi-indoor Holstein calves affected performance, body measurements and health status in the preweaning period throughout the winter months. A total of one hundred calves were allocated into two treatment groups (control and jacket) in terms of their weights and sex. The calves throughout the study period were raised at individual calf hutches in a semi-open barn. All calves and the consumed concentrate intakes were weighed every 28 days to determine body weight (BW), average daily gain (ADG), total and daily feed consumption (TFC, DFC). Incidence rate (IR) ratios were calculated from the records of daily health assessments. Calves in treatment group were jacketed from first to 45 days of age. The weaning process started gradually at 56 days of age and the calves were weaned on day 63. No significant effects of wearing jackets in terms of body measurements and performance. The respiratory diseases IR was 1.15 times higher in calves without jackets, which means that calf health was positively affected by wearing jackets. The improved health status of the treatment group showed that wearing jackets may protect calves from adverse effects of cold stress. There is a need for more comprehensive studies about the effect of calf jackets in early periods of preweaning, especially in calves in outdoor hutches.