Behavior of Transition Dairy Cows Managed Outdoors During the Autumn and Spring Calving Seasons.

In pasture-based systems, prepartum dairy cows can be exposed directly to weather conditions during the transition period. We aimed to determine how temperate climatic conditions during spring and autumn calving seasons affect transition dairy cows' lying and ruminating behavior in outdoor conditions. Behavior and meteorological data were extracted from two external experiments carried out during the spring calving season and the autumn calving season. Mixed models were used to determine the effects of weather conditions on daily lying and rumination behaviors. In the spring calving season, high precipitation reduced the daily lying time, and the wind speed decelerated this effect both in the pre-and postpartum period. High precipitation combined with low air temperature or wind speed favored the rumination time in pre- and postpartum periods. In the autumn calving season, lying time was reduced as air temperature and wind speed increased during the prepartum period, and solar radiation increased in the postpartum period. The rumination time was reduced under warm conditions (high temperature/solar radiation) in pre- and postpartum periods. These findings suggest that under a temperate climate, the weather of both calving seasons has important implications on behaviors associated with comfort, such as lying and rumination.