Compost-bedded pack barns are an alternative to traditional freestall barns, typically offering additional space for roaming and lying down for lactating, dry and special-needs cows.
“We have been using our compost-bedded pack barn for eight years. Previously, we had freestalls, and the cows would also go out to pasture – but we found that in Kentucky, when it rains so frequently, it was difficult to get the cows outside,” says Gail Ballance of Ballance Farms Inc. in Oakland, Kentucky, who milks 240 cows three times per day.
“We were also using freestalls when the size recommendations were much smaller, and we felt like our cows weren’t getting enough space to rest.”
Another problem Ballance Farms noticed was the time to keep the freestalls clean, manually pitching out manure while the cows were milked. But with the compost-bedded pack barn system, that time was greatly decreased.
“We use sawdust for the bedding and run a field cultivator through it three times per day after the cows exit to be milked. Our set-up takes about 10 minutes to go back and forth each way in our 100-foot-by-200-foot barn,” Ballance says.
In making the transition to a compost-bedded pack barn, Ballance says they noticed a decrease in their somatic cell count and found it easier to maintain a low count.
“We shipped to Dean’s in 2016 and were receiving awards consistently for maintaining a somatic cell count of less than 100,000,” she says.
Researchers are still exploring the correlation between compost-bedded pack barns and low somatic cell counts.
“We are finding, in some cases, herds with lower somatic cell counts with compost-bedded pack barn systems are more equipped to deal with the pathogenic challenges on the horizon because the compost allows them to express their behaviors more naturally, decreasing stress,” says Matthew Borchers, a Ph.D. candidate at the University of Kentucky, exploring compost-bedded pack barns.
While these barns can and have decreased somatic cell count, they are management-intensive.
“These barns are great, but they aren’t for everyone. It is similar to what nutritionists do by feeding micro-organisms in the rumen but, in this case, management is making decisions to try to enhance microbial activity, which involves frequent tilling of the bedding area,” Borchers says.
Managing the moisture content is critical to maintaining the microbial population of the pack.
“It is important to keep it oxygenated to prevent the bedding from transitioning to an anaerobic environment, when bacteria can become an issue,” Borchers says. “If you get changes in the moisture, you see changes in the microbial population, which can increase mastitis and increase somatic cell count.”
To check moisture content of the bedding pack, Borchers and other researchers recommend taking a handful of the bedding and clenching it into a ball. If you bounce it, and it breaks apart easily, then the moisture content is fine – but if it sticks in ball form, then the moisture is too high, and more bedding needs to be added.
“We typically add sawdust twice per week in the winter and once a week or less in the summer,” Ballance says. “We watch the cows, and if the bedding starts sticking to them, then we add more – the drier, the better. Our barn has 4-foot walls, and we clean out the barn completely once a year.”
Ballance Farms also adds to the bedded pack when the cultivator experiences clotting when it runs through the barn before milking.
“We typically recommend 40 to 60 percent moisture content,” Borchers says. “It’s not an issue if it’s less than 40 percent, but if it’s greater than 60 percent, that’s when we see the real issues. Once you get out of the 60 percent moisture range, it changes the microbial population and selects for anaerobic bacteria, and then the temperature of the pack will drop.”
With an 8-inch compost-bedded pack setup, researchers recommend maintaining a temperature of 110 to 140ºF.
“When you get out of [that] range, other bacteria start, and they aren’t inhibited by those temperatures, so that’s where we see cases of mastitis,” Borchers says.
Overcrowding in compost-bedded pack-style barns also becomes a greater concern than in sand or freestall barns, resulting in increased compaction and higher moisture content from increased manure and urine.
“Our barn is made for 200 cows, following the recommendation of 100 square feet per animal, with a minimum space requirement of 80 square feet per animal,” Ballance says. “In the winter, we do push the 80 square feet per animal, but we also have another compost-bedded pack hoop barn that will house an additional 40 cows.”
For producers considering compost-bedded pack barns, Ballance encourages building not only the barn but also a building to house the bedding material.
“It takes a lot of sawdust. We didn’t have a building to store the sawdust the first year and wished we had to be able to store the sawdust when it is plentiful in the summer,” Ballance says, noting a decrease in availability of sawdust in their first winter.
These systems can be a more affordable solution for producers looking to expand their operation in places where sawdust is both plentiful and affordable.
“It can be a cheaper alternative to freestall housing because there is less cost per cattle, without the purchase of loops and smaller amounts of concrete required during the building process,” Borchers says.
As with all housing systems, success of the compost-bedded pack barn comes down to good transition cow management.
“Any housing system can accomplish what a dairy producer wants,” Borchers says. “It is primarily about maintaining the comfort of the cow and not exposing her to stress or large quantities of mastitis pathogens. Compost-bedded pack barns aren’t the answer but are a system that can work.”
PHOTO 1: Gail and Bill Ballance milk 240 cows on their dairy near Oakland, Kentucky
PHOTO 2: The Ballances’ barn holds 200 cows, allowing for about 100 square feet per cow. One of the keys to managing a compost-bedded pack barn is keeping it oxygenated, says University of Kentucky Ph.D. candidate Matthew Borchers. Photos by Emily Gwin.
Ashley Curtis is a freelance writer from Oakdale, Minnesota