Heat detection was a big challenge for Four Henry Holsteins, says dairy partner Mark Henry, who farms with his brothers and several other family members near West Liberty, Ohio. So, several years ago the farm instituted an Ovsynch protocol in its reproductive program, and it worked well, with about 90 percent of cows bred off of that protocol.
But, as concerns over public perceptions of farming practices have come to the forefront, Henry says he began to think about what would happen if consumers adopted the same attitude toward reproductive programs and hormone tools as they did toward recombinant bovine somatotropin (rbST).
With that in mind, the dairy — which was in the midst of an expansion to 500 cows — decided to take an automated heat detection system for a test-drive and reduce its dependence on reproductive synchronization therapy. The Henrys are not alone in their decision to explore automated systems; farmer interest has ballooned recently and at least eight proprietary systems are currently available in the U.S. (Additional systems are expected to hit the market soon.)
Here’s the scoop on this technology.
Q. What is an automated heat detection system?
A. It is an interconnected system of devices that automatically monitors and measures cow activity associated with the onset of estrus (heat) without the need to visually observe cows.
These devices may include pedometers or activity meters, the communication technology needed to send data from these monitors, and software to analyze that data.
Accurate estrus detection with minimal labor requirements and optimal timing of AI relative to ovulation are the primary factors to look for in an automated system, say researchers from the University of Guelph.
Q. What are these systems trying to track?
A. “Almost 100 years ago, and before we knew about hormones, physical activity of rats was linked to the functional status of ovaries,” explains Roy Fogwell, Michigan State University animal science professor. Since those early studies, ovary status has been linked to physical activity in virtually every mammal. (For more information, go to: https://www.msu.edu/~mdr/vol16no3/fertility.html)
As cows approach estrus and ovulation, a significant increase in physical activity occurs before the overt mounting and standing activity associated with heat detection starts. However, Fogwell notes, people encounter several problems in heat detection.
“Even among healthy cows, duration and intensity of estrus vary widely,” he says. Activity can vary due to the number of cows in estrus, hot or cold ambient temperatures, stocking rate, number of non-pregnant cows, lameness or illness.
If visual heat detection occurs twice daily, successful estrus detection is typically less than 50 percent, he says, and that is not acceptable for most dairies. These automated systems offer a means to improve that track record without having to perform the administration duties of a synch protocol.
Data from automated systems give users three possible conclusions with which to evaluate individual cows: the cow is in estrus, the cow needs to be examined in person for other signs of estrus or no action is needed.
Q. Are pedometers and activity meters the same thing?
Pedometers are generally electronic devices that measure walking activity or steps and are usually in a device attached to a cow’s leg. Activity data is transferred during milking via a walk-through portal near the milking parlor or with a stall reader in the parlor. This means data is usually downloaded two or three times a day, based on milking frequency.
These tools to detect dairy cow estrus have been around since the 1970s.
Activity meters arrived on the scene more recently. They have three basic components: on-cow monitors that measure movement, a base station that collects this data and a computer or control box. Monitors collect data 24 hours a day, seven days a week. Depending on the system, data can be downloaded automatically at predetermined intervals or by a reader that the cows must pass under. While the monitors transmit wirelessly, communication between the base station and analytic components may be via coaxial cable or wireless technology.
Q. Do these automated systems work to help get cows pregnant?
A recent University of Guelph study of three free-stall commercial dairy herds (1,429 cows) in Ontario, Canada found that overall herd and cow-level reproductive performance was not different between the timed AI protocols and automated heat detection-based reproduction management systems. An interaction between breeding program and herd demonstrated that automated activity systems performed equally or better than a timed AI program in a situation in which very little AI was based on observed estrus. (Go to: http://bit.ly/ornZP4 for more information)
Furthermore, Ray Nebel, vice president of technical service programs for Select Sires reported at the 2010 Dairy Cattle Reproduction Council’s annual meeting about an 800-cow dairy that achieved a 25 percent 21-day pregnancy rate using an automated heat detection system. In this herd, only 23 percent of cows were inseminated on first service as part of a timed AI protocol.
Anecdotally, Mark Henry says that 21-day pregnancy rates have gone from 14 percent to 21 percent since installation of the automated heat detection system. “We can breed cows on time now; previously, we didn’t know exactly when she’d be in heat.” The dairy still uses a synch protocol on problem breeders, but Henry is pleased with the more targeted nature of this strategy vs. the previous across-the-board application.
Q. What are the advantages of an automated heat detection system?
A. The benefit to monitoring activity is that cows do not have to be injected or observed, thus potentially saving labor and reproductive hormone cost, Plus, the ability to more accurately detect the onset of estrus should lead to better timing of AI, and increased reproductive performance.
“The biggest benefit of the system for us has been with our heifers and getting them to calve in at an earlier age,” Henry says. “And we’re seeing an improvement in herd calving interval, which will help with overall profitability.” The dairy elected to purchase the system following the trial period, and Henry adds that it is “a big step in the right direction for us. We’d do it again.”
Q. Are there disadvantages?
A. Of course. As with any management tool there is a learning curve following adoption. You’ll need to learn what the data means and how to incorporate the results into your daily routine. It takes time to differentiate between a “true” peak in activity caused by a cow in heat from a “false” peak in activity due to other causes for an increase in cow activity, cautions Nebel.
You may also need to alter your breeding schedule. For example the herdsman at Four Henry Holsteins checks the computer four times a day to see if any animals need to be inseminated. If you are unwilling or unable to make a change in daily duties, you may not get the results you desire.
Also check out the hardiness of system components. As Henry notes, “electronics and moisture don’t mix.”