CORVALLIS, Ore. – If you want a dairy cow to produce as much milk as possible, one of the things you need to do is make sure she spends enough time each day just lying down, content and at ease. But to be happy, she's got to be comfortable in her pen or wherever she is.
Wanting to help dairy farmers learn more about this to maximize their milk production, Oregon State University has launched research to study the factors that influence dairy cows' comfort level. To do this, the OSU dairy center is using an Israeli-made ankle bracelet that senses when a cow is lying down by determining the angle of her leg to the ground. When a cow lies down, the blood flow to her udder increases, which produces more milk.
"This device is a way for the cows to tell us things," said Aurora Villarroel, an OSU Extension veterinarian in the College of Veterinary Medicine who is conducting the research. "It's a way for us to interpret what they're doing without being there 24-7 or filming them."
Villarroel and her team attached the device, which is orange and about the size of a deck of playing cards, to about 100 cows earlier this year and began gathering baseline data. Now she's asking dairy farmers what factors they'd like OSU to test. She's encouraging dairies to contact her at 541-737-5853 with their ideas or questions. She aims to start testing some of their suggestions this summer.
The factors can vary from environmental to nutritional. For example, researchers may see if straw bedding makes a cow lie down more than sand or if separating Jerseys from Holsteins instead of having mixed herds affects their time on the ground, Villarroel said. Or perhaps they'll tweak the size of the freestalls or the number of cows in a pen and see what happens, she added. Additional factors might be drastic weather changes, what the cows eat, and times of milking, she said.
Whatever the factors might be that influence the amount of time a cow rests, the bottom line is that more time on the ground equals more milk, according to research. A study by the William H. Miner Agricultural Research Institute in New York looked at how much milk was produced by cows that rested between seven hours and 17 hours a day.
"We found a positive correlation between those two variables," said Peter Krawczel, a research assistant at the institute. "The result was that we predict that for each additional hour of rest, there would be a gain of 3.7 pounds of milk."
For example, he said, if a cow normally rests for seven hours a day, but increases her rest to eight hours, then her milk production would increase 3.7 pounds that day. If she rested for nine hours, she would produce 7.4 more pounds that day, he said.
Those extra pounds mean extra cash for dairies. In Oregon, dairy farmers grossed $500 million in milk sales in 2008, according to a preliminary report by the OSU Extension Service. In terms of farmgate sales, milk was Oregon's third largest commodity group after cattle and nursery crops, the report said.
OSU isn't just using the ankle bracelets to record cows' resting habits though. The device, which is made by SAE Afikim, also works as a pedometer, counting how many steps a cow takes each day. This helps dairies know when a cow is ready to be bred because cows' activity levels increase when they're in heat.
Once the cows are in the milking parlor, a sensor transmits the data in their ankle bracelets to a computer where it can be analyzed. Custom reports can then be made for herds and individual cows.
Although using pedometers to detect heat in U.S. cows isn't new, OSU is the only facility in the country that is using ones that sense if cows are lying down, said Udi Golan, a products manager for Afikim who talked about the device during an open house at the dairy center this month. He said Afikim plans to start selling pedometers with this tilt-detecting sensor in the United States in a few months. Dairy equipment provider DeLaval will distribute them.
Also at the open house, Ben Krahn, the manager of the center, explained how he and his crew are using other technology that is new to the center, which is run by the animal sciences department in the College of Agricultural Sciences. A few weeks ago, they began using radio frequency identification tags on the cows’ ears that function as barcodes.
Cow handlers wave a wand next to them and the cow’s personal medical record immediately appears on a handheld computer. Data include the cow's birthdate, when she was bred, who her parents are, when a veterinarian last examined her, and how much milk she has produced. Examiners can also input data into the handheld device, which is about the size of a small paperback book.
Having a computer at a cow's side means that examiners don't have to run back to an office computer and look up data or possibly make mistakes while jotting it down on a clipboard, said David Nansel, an account manager for Utah-based DHI-Provo, which makes the software.
DHI-Provo asked OSU to test it out so the company can fine tune it for the industry, Nansel said.