September 20, 2020
Activity monitoring systems have been in use for many years as tools to manage breeding of dairy cattle; the first recorded use of an electronic system for this purpose was 1954. In recent years, there has been a great increase in the number of activity monitoring systems available on the market. Not only are there more options available, but they are used for more than a heat detection tool. These modern activity systems have the ability to monitor rumination, cow temperature, cow location within the barn, cow position (lying vs. standing), eating time, and more. With the increased functionality, these systems are being used increasingly to monitor overall cow health.
The transition period, from approximately 21 days pre-calving to 21 days post-calving, is a period of particular concern for the health, production, and profitability of the dairy cow. Metabolic and reproductive health issues associated with the transition period; including displaced abomasum, ketosis, milk fever, dystocia, metritis, and retained placenta, are common causes for early removal of cows from the herd. Data from the USDA has shown that approximately 20% of dairy cows will leave the herd within the first 50 days post-calving.
A case study was conducted on a dairy farm in southeastern Pennsylvania to evaluate the effectiveness of an activity monitoring system in detecting changes in daily activity and rumination patterns during the transition period of Holstein cows.
Case Study Farm and Data Collection
From April 2017 through February 2018 average daily activity and average daily rumination data were collected using an SCR activity system. The farm housed approximately 650 lactating Holstein cows with an average milk production of 88 pounds per cow per day, 3.6% fat, and 3.0% protein. Cows and bred heifers were fitted with activity collars 45 to 60 days prior to the expected calving date. Activity and rumination data were collected from the time activity collars were placed on them until a minimum of the first 60 days post-calving or until cows were culled or died. The farm recorded calving date, date and type of health events (ketosis, retained placenta, displaced abomasum, etc.), and date cows left the herd.
Based on farm records, cows were divided into 3 groups as determined by their health status following calving. Groups were defined as:
NO EVENT = cows that had no early lactation health events reported and remained in the herd for a minimum of 60 days post-calving
RECOVERED = cows with one or more early lactation health event reported but recovered and remained in the herd
LEFT = cows with one or more early lactation related health events reported and were culled or died within the first 30 days post-calving.
For purposes of this study; early lactation health events included metritis, displaced abomasum, retained placenta, ketosis, and milk fever.
Case Study Results
Average daily rumination and activity (Figure 1) patterns for all cows are shown from 21 days pre-calving until 28 days post-calving. Pre-calving, daily rumination for the herd averaged 490 minutes per cow per day. Average daily rumination and activity patterns were similar across the three groups; however, there were apparent differences in the activity and rumination patterns between groups, during the pre-calving and post calving periods. Most notably, rumination was numerically lower in cows in the RECOVERED group compared to cows in the NO HEALTH EVENT group pre- and post-calving (Figure 2). Additionally, activity levels pre- and post-calving were numerically lower for the LEFT group compared to cows in RECOVERED group (Figure 3).
Results indicate that activity and rumination data during the pre-calving period could potentially be used as a tool to help farmers detecting cows that may be at a higher risk of becoming ill or leaving the herd during the first 30 days in milk. This early warning could provide farmers with an opportunity to implement best management strategies for these at-risk animals, allowing them to cope better with transition period challenges, and therefore, decrease the risk of becoming sick or leaving the herd.