Cross ventilation and compost-bedded pack barns are increasing cow comfort and productivity in some US herds.
Cross-ventilated barns: What are they?
Cross-ventilated barns have had a presence in the USA for nearly a decade and are a new spin on traditionally ventilated barns.
Often used in larger operations of 500 or more cows, these completely enclosed barns feature fans that line the length of the facilities, which can range from 200- to 500-feet wide. Along the other length of the enclosed barns are cooling pads.
Fans pull cooled air across the width of the barn and across interior baffles – often made of metal or weighted cloth – which run the length of the barn and extend down to within seven feet of the floor, forcing air down on to the cows as they rest in free stalls.
Marcia Endres, University of Minnesota associate professor of dairy science, says the greatest advantage can be seen in larger operations.
“Larger producers can put all cows under one roof – with up to eight to 20 rows – rather than in two or more buildings.”
Dr Endres says a cross-ventilation system allows for a more consistent environment for cows year-round.
“The winter is not as cold and doesn’t freeze as much,” she says. “And in the summer, the temperature can be cooled by 5-15F with the cooling pads.”
In a study comparing cross-ventilated, naturally ventilated and compost-bedded pack barns, led by Dr Endres, cross-ventilated barns with evaporative cooling pads were 2-3C cooler than naturally ventilated and compost-bedded pack barns when the outside temperature was greater than 27C.
Farmer case study
Jeff & Fred Beer, Beer Farms, Milford, Indiana
- 890 cows
- 13,290kg a cow a year
- 15 full-time and some part-time staff
- Three-times-a-day milking
- 283ha – 40ha soya beans, 243ha corn
Jeff Beer and his father Fred, of Milford, Indiana, installed their cross-ventilated barn in 2008. This barn, which contains 640 freestalls, is divided into eight pens and is lined with 40 fans along the length of the facility.
Jeff Beer says they chose a cross-ventilated barn for cow comfort and because it made sense financially.
“In naturally ventilated barns, which we already had, we have tons of fans throughout the barns anyway,” he says.
“We toured several cross-ventilated barns in Minnesota and we liked the design. When we started looking at the cost, it was very close to a naturally ventilated barn, which was about $1,800 (£1,113) a stall. So why not go for it?”
In addition to the facility cost, Dr Endres says producers may experience a slight increase in electricity costs, as fans run year-round and backup generators are a “must”.
“For the most part, producers need two backup generators,” she says. “In the summertime in confinement facilities, cows will die of overheating if the fans and cooling system break down. Producers cannot be without generators, in case there is a power failure.”
Because the cooling system works through evaporation, high humidity can lead to decreased effectiveness of the system,
Mr Beer explains. And, his location in north-central Indiana can see its share of humidity, with average summer temperatures reaching 27C.
“In high humidity, the cooling pads can add more moisture to the air, which already cannot hold any more moisture,” Mr Beer explains. “And when it doesn’t cool down at night, the humidity keeps building.”
But Mr Beer believes increased cow comfort has been worth the cost and challenges.
“With a barn as large as this, we have seen many cows under one roof that are peaceful,” he says.
“In extreme heat, we can see about a 10F difference in temperature, and with the good breeze, it can increase cow comfort greatly. We had one day this summer that was 39C, and the barn temperature read 28C.”
The herd actually experienced a jump in milk fat and protein counts immediately after the move into the new barn.
Overall, Mr Beer says increased cow comfort is important to their operation for a variety of reasons.
“If the cow is comfortable, lying down and not stressed and if the cow can be cool, not be disrupted and away from heat stress, we see a definite response in production,” he says.
Compost-bedded pack barns: What are they?
A compost-bedded pack barn is a loose housing system with no stalls, explains Jefferey Bewley, University of Kentucky assistant professor of animal and food sciences.
“You start with a layer of sawdust or other biomaterial, and the cows add their urine and manure to it.
The farmers stir it twice a day with a field cultivator or tiller while the cows milk, and it creates a composting system.
The resulting product looks like potting soil and is a nice material to add to the fields, and the cows have a soft bed to rest on.”
Farmer case study
Angie & Bob Klingenfus, Harvest Home Dairy, Crestwood, Kentucky
- 150-cow herd
- 9,071kg a cow a year
- Three full-time staff, in addition to owners Angie and Bob Klingenfus
- Twice-a-day milking
- 445ha – 80ha soya beans, 80ha corn, 40-60ha hay
Angie Klingenfus and her husband Bob have owned Harvest Home Dairy, Crestwood, Kentucky, for 26 years.
They have continually updated older facilities to increase cow comfort and production through the years. Until they ventured into the compost-bedded pack barn system, they’d seen little success, she says.
“Our facilities were old and outdated, and the cows were terribly uncomfortable in the free stalls,” says Mrs Klingenfus.
“We had mattresses filled with chopped rubber tires, and they were too uncomfortable. Our cows had foot and leg problems. And because the barns were too hot in the summer, production dropped each summer.”
Perhaps one of their greatest concerns were the herd’s somatic cell counts, which were more than 500,000 cells/ml at times.
In addition, she says, their farm lies next to a major creek, which is a tributary to the Ohio River. They were constantly dealing with issues of liquid manure storage and spreading, and preventing environmental issues from run-off.
“We were to the point of either quitting or changing our system,” says Mrs Klingenfus. “We love what we do. So we starting looking at how to change.”
They began researching compost-bedded pack barns and toured farms that used these structures.
“We loved them,” she says. And because they did, they made the switch last November. The result, Mrs Klingenfus says, is a complete turnaround of their operation.
“The whole demeanor of the cows changed. They actually seemed more energetic and lively. Our production increased. And I can see a lot more cows in standing heat, knowing when to breed.”
Because of reduced concrete surface area, Mrs Klingenfus says she’s also seen reduced cow injury from slippage on wet concrete.
“And as soon as two months after the switch in facilities we’ve also seen a drastic reduction in foot problems,” she says. “We used to sell so many for foot problems. Now the only reason we sell is because they’re too old or the production has dropped.”
And within a few months in the new facility cell counts dropped below 200,000 cells/ml. “We don’t have the mastitis problems and sickness. And my vet bills have definitely gone down.”
However, Dr Bewley says farmers must be dedicated to stirring the compost twice daily for the system to work.
“It’s a 15-minute job twice a day,” he says. “But it does take a higher level of management – managing the composting process. The compost process could die and cows could develop mastitis problems if it’s not properly managed.”
Mrs Klingenfus believes careful monitoring can help with management. “If you’re not tilling it twice a day, the compost will get really wet and it won’t work,” she says.
Dr Bewley says farmers must realise a compost-bedded pack barn is not just cow housing – it’s also manure storage.
“Farmers typically clean out these barns once a year – and when it’s really working well, I’ve seen it go as long as three years without being cleaned out,” he says.
Mrs Klingenfus says in the year they’ve used the system, they’ve cleaned out their barn once.
“We can choose the time,” she says. “And we can spread the compost at our convenience.”