The short-term effects of altering milking intervals on milk production and behavior of holsteins milked in an automated milking system

Authors: DAVID, LINDSEY - Clemson University; French, Elizabeth; AGUERRE, MATIAS - Clemson University; AHMED, ALI - Clemson University

Submitted to: Dairy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/19/2024
Publication Date: 7/24/2024
Citation: David, L., French, E.A., Aguerre, M.J., Ahmed, A. 2024. The short-term effects of altering milking intervals on milk production and behavior of holsteins milked in an automated milking system . Dairy Journal. https://doi.org/10.3390/dairy5030032.
DOI: https://doi.org/10.3390/dairy5030032

Interpretive Summary: Automatic milking systems, has become more widespread across US dairy farms. One advantage is the ability of cows to create individual milking, feeding, and resting schedules apart from their counterparts. Changing the cow's milking permission, or how often the cow can visit the robot impacts cow behavior, welfare, and system efficiency. The influence of the cow's parity was also evaluated. We hypothesized cows that are changed from a four-hour milking interval to six hour would exhibit greater signs of stress based on heart rate variability than cows that continued on a four-hour milking permission interval. Test cows that were transitioned to six hour intervals demonstrated increased signs of stress based on heart rate variability parameters after the adjustment. Additionally, it was determined test cows changed their daily routine by increasing lying time, particularly during the day. Within parity, no differences were observed between treatments in milk production, milking frequency, or milk yield per visit. However, it should be noted that only one experimental herd and a single barn design were included in the current study, thus, providing a very specific description of events. In the future, the inclusion of numerous experimental herds and differing group sizes may help lead the industry to an ideal solution to promote optimum group mixing and cow behavior within the AMS and the impact of daily behaviors on feed efficiency.

Technical Abstract: The widespread adoption of automatic milking systems (AMS) in the United States has afforded dairy cows the flexibility to establish personalized milking, feeding, and resting schedules. Our study focused on investigating the effects of transitioning milking permissions from every 4 to 6 hours on the 100th day of lactation. Twenty-four Holstein dairy cows at LaMaster Dairy Farm AMS facility were divided into control (maintaining a 4-hour milking interval) and test groups (transitioning to a 6-hour milking interval) and observed for 6 days. The analysis revealed that parity and treatment had no significant impact on milking frequency, milk/visit, or daily milk yield. However, multiparous cows spent more time inside the commitment pen, while test group cows exhibited heightened approach AMS frequencies, tail-swishing, displacement behavior, and longer idle times. The interaction between parity and treatment influenced Heart Rate Variability (HRV) parameters, indicating increased stress in the test group cows. Additionally, the test group cows showed higher total and daytime lying frequencies, suggesting behavioral modifications. Despite no immediate impact on milk production, further research is recommended to assess the potential long-term effects on milk yield in AMS farms, considering the identified stress indicators.