Pons, M. V., Adrien, M. L., Mattiauda, D. A. et al. 2023. Welfare of dairy cows in mixed feeding systems under two different conditions of confinement: Behavioral, biochemical and physiological indicators. Applied Animal Behaviour Science 265, 105995.

High production pasture-based dairy systems have difficulty meeting cows' nutritional and environmental needs, especially during extreme environmental conditions during summer in temperate zones. The mixed systems combine pasture access with supplementation periods to achieve the maximum use of pastoral conditions and help better meet nutritional requirements. The aim of this study was to determine if the different conditions during confinement (compost barn, CB vs. outdoor soil-bedded, OD) affect behavioral, biochemical and physiological indicators of welfare in dairy cows. Multiparous Holstein cows were randomly assigned to one of two groups for confinement periods: a compost barn (CB, n = 15): consisting of compost bedding, a roofed area, ventilation and sprinklers, and an outdoor soil-bedded area during (OD, n = 15), which had a soil floor and shaded area. The frequency of eating, ruminating, drinking, lying, standing, and walking behavior in confinement was evaluated for three months during summer. Rumination minutes was recorded with collars automatically throughout the day. Blood samples were taken to determine total proteins, albumin, globulins and creatine kinase. The subcutaneous temperature was recorded during December and January (n = 7 per group). During the confinement, the CB cows spent more time lying down (P = 0.001) and ruminating (P = 0.04) than the OD cows. During pasture access, the CB cows spent more time grazing (P = 0.003) and less time ruminating (P < 0.0001) than the OD cows. Furthermore, the CB cows had lower subcutaneous temperature than the OD cows during the day (P < 0.0001). Serum creatine kinase concentrations tended to be higher (approximately 360 % more) in the OD cows than in the CB cows (P = 0.07). Differences in the type of confinement determined behavioral changes during both the confinement and pasture access, demonstrating the adaptability of cows to a varied environment. In conclusion, the different conditions during confinement affected the welfare indicators of the dairy cows in the mixed system during summer, with OD cows experiencing poorer welfare than CB cows, based on behavioral, biochemical and physiological indicators of welfare.