This article was #23 of the Top 25 most well-read articles on www.progressivedairy.com in 2014. It was published in the Feb. 4, 2014 Extra e-newsletter. Pennsylvania Extension veterinarian David Wolfgang and Extension engineer Dan McFarland teamed up to provide best practices for bedding barns.
While they acknowledged that many bedding options exist, the ultimate goal is to provide an environment that results in clean, comfortable cows quantifiable by the following parameters: 90 percent or more of the cows with a hygiene score of “clean” or “very clean,” 90 percent or more with minimal evidence of hock trauma, less than 15 to 20 percent with rough, cracked teat skin and standard plate counts of less than 1,000 colony-forming units (cfu) per mL and coliform plate counts less than 50 cfu per mL.
We asked the team,
Q. What advice do you offer for cleaning and maintaining stalls in order to provide cow comfort and a clean, dry environment?
A comfortable resting surface improves stall use. Observation indicates that cows prefer well-designed stalls with a generous layer (4 to 8 inches) of bedding material. Mattress stall beds and “soft” mat options can produce similar results, but their cushion and conforming properties only replace a percentage of comfort versus generously bedded stalls. The responsibility for keeping stalls clean and dry lies with the caregiver and management. Removing manure and soiled bedding from the stall surface three times per day is recommended. Bedding removal and addition varies between materials and seasons. Organic bedding materials usually require more frequent replacement.
Since the cow’s first step into the stall lands where the udder will soon rest, alley cleanliness is very important. Proper ventilation provides air exchange to remove moisture, promoting drier cow alleys and stall beds. Overpopulation leads to higher average daily stall use and more opportunity to contaminate the stall surface.
—David Wolfgang, Extension veterinarian, and Dan McFarland, Extension engineer
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Meal goes in, milk comes out, but cows aren't that simple. During a Penn State Extension "Technology Tuesdays" webinar presentation held Dec. 10, 2013, Extension veterinarian David Wolfgang and Extension engineer Dan McFarland discussed recommended practices for dairy cow bedding.
The presentation divided bedding into two general types: organic and inorganic. Organic bedding materials include paper products, straw, hardwood sawdust, softwood sawdust and manure solids. Inorganic bedding materials include sand, lime and mattresses.
For organic materials, "pine shavings are probably the gold standard," Wolfgang said. "Just taking pine shavings by themselves, adding moisture, adding heat, as long as they're clean, they're probably the gold standard." Wolfgang prefers inorganic bedding materials.
Wolfgang prefers inorganic materials because they lack carbohydrates, decreasing bacterial load in clean bedding. "Recycled sand can work great. We like to have people stack it for a time outside or under cover, to let all the water drain away," Wolfgang said. With adequate drying, Wolfgang said that recycled sand can be almost as clean of a bedding material as fresh sand.
Why is bedding important? Having clean bedding is a “win” for the cow and her owner. The presentation listed decreased somatic cell count, better hygiene scores, decreased prevalence of Johne's disease and salmonella, and decreased food requirements in bad weather as benefits of clean cows. "Maintaining a stall bed with a lower bacteria count tends to reduce the risk of mastitis. Not eliminate, but reduce the risk," Wolfgang said.
McFarland emphasized cow comfort in his recommendations, noting that cows spend 10 or more hours resting per day. "There are some good studies that have been done at the University of British Columbia. They have video results of cows sniffing at a stall, looking for the dry one." McFarland and Wolfgang recommend bedding that is at least 60 percent dry material.
"If you put your knees down on the bedding, and they get wet, it's too wet. You really should be able to kneel in the stall area and not have wet knees. If you take your fist and ball up the bedding, it should not stay in a ball. It should just fall apart. It should be too dry to be made into a ball. And that usually translates into a dry matter of greater than 60 percent," said Wolfgang.
A common problem that Wolfgang has encountered is over-application of bedding. "People fill the entire front of the stall with a week's worth or two weeks' worth of bedding, and then just keep pulling that material back from the front," Wolfgang says. The piled bedding fosters bacteria growth. "So now you're bringing back clean material, but it's pre-incubated with millions of bacteria. The animal lays down, suddenly the teats are in contact with millions of bacteria, and the odds of mastitis go up."
McFarland says that proper bedding maintenance regimes have increased bedding volume and more frequent applications of new bedding, with more frequent grooming of beds.
Cow comfort is also determined by the size of the stall. McFarland recommends sizing tie stalls and free stalls by the largest cow in the herd. "I like to see cows in the restful posture. The cow is 4 to 6 inches ahead of the rear curb in the stall," said McFarland. "Rear leg movement is greatly reduced, and hock injury is reduced as well."
For bedded packs, McFarland recommends 100 sq.ft. per lactating cow, 80 sq.ft. per far-off dry cows, 120 sq.ft. per close-up dry cow, and 140 to 200 sq.ft per pregnant cow.
"For aerated or composted bedded packs, where they're tilled regularly, you'll want to see a finer material," McFarland said. The traditional option was kiln-dried wood chips, but McFarland lists generous green sawdust, processed horse bedding, sawdust and long straw as modern options.
Wolfgang also recommends proper use of pre- and post-milking dips, but with some cautions. In cold weather, iodine dips tend to dry more slowly, risking frostbite and chapping. Teat sealants are effective if they last long, but Wolfgang said they do not eliminate the need for dry housing for dry cows. "Just because they are not lactating does not mean they do not need a clean and comfortable place to live as well."
Wolfgang's goal for cows are quantifiable: 90 percent or more cows with hygiene scores rated clean or very clean, 90 percent or more with minimal evidence of hock trauma, less than 20 to 15 percent of cows with rough or cracked skin at the teat, standard plate counts of less than 1000 cfu/mL and coliform plate counts of less than 50 cfu/mL.
"We know that facilities that have very clean cows and a clean parlor can maintain low coliform counts," said Wolfgang.
But cell counts and bacteria counts are only part of the picture.
"You need to ask the question, too, of how many [cows] are being held out of the tank? Those are the animals that may be suffering from those environmental infections, and that milk is not going into the tank," McFarland said.
"I'm confident that we can convince cows to rest at the proper 10 to 14 hours per day that they want to, with the proper stall sizes, with the proper bedding," McFarland said. "But realize that during those 10 to 14 hours, these cows are in contact with some type of bedding material that could cause environmental infection."
"Taking extra effort to provide a resting area that's comfortable is an essential part of any dairy system," McFarland said. "The proof in the pudding is the management of the system."
Bedding management, resting area grooming and management, manure management, keeping aisles clean, keeping stalls dry with ventilation and preventing overcrowding are all part of a quality resting area.
Click here for the full webinar, and here for additional materials. For more detail on stall design, McFarland recommended the "Updating Dairy Stalls" and "Design and Management of Quality Cow Resting Areas" webinars. PD
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Stock image.
