| The periparturient period, defined as three weeks prior to and three weeks after parturition, is a time of great physiological, environmental, and social stress for dairy cows. This transition into lactation is often marked by negative energy balance, oxidative stress, and impaired immune function. These factors combine to create the perfect storm to challenge a cow's homeorhesis. The periparturient period has been well characterized in cows in traditional dairies that are milked at a fixed frequency in a parlor and fed a total mixed ration, however, little research on alternative milking and feeding systems exists. One such system is a combined pasture-based automatic milking system (AMS) dairy. This combination of milking system and diet is still relatively uncommon, however, there are many potential benefits for both cows and producers. Despite the growing interest in pastured-AMS dairies, there is little information available regarding how the periparturient cow is impacted by this milking system and diet. Therefore, the aim of this research was to use physiological, production, and behavioral data to evaluate the health and welfare of pastured multiparous and primiparous cows milked in an AMS during the periparturient period. Results indicate that multiparous and primiparous cows experience metabolic and oxidative stress and changes in pro-inflammatory cytokine expression, but that there is not a dramatic difference between parities or during the periparturient period. Non-invasive behavioral measures and production data support these results. Indeed, a well-managed pasture-based system combined with the correct implementation of AMS seems to offer benefits and does not negatively impact cows during the critical periparturient period. |
