Adding fans in freestall barns improves environment for cows

PEARL CITY, Ill. — Tunnel ventilation of the freestall barns at Hunter Haven Farms provides improved airflow for the cows throughout the year.

“We tunnel ventilated the original barn about 10 years ago and we gained some cooling capacity in the summer,” said Scott Brenner, Hunter Haven Farms. “And also a much nicer environment for the cows in the wintertime, so I think we see as much benefit in the winter with the tunnel ventilation as we do in the summertime.”

Brenner is currently in the process of adding tunnel ventilation to the second freestall barn.

“We’re going to close the sidewalls and my goal is 7 to 9 mph wind speed throughout the barn,” said Brenner during the 2021 Virtual Dairy Tech Tour sponsored by the Illinois Milk Producers Association and the University of Illinois Dairy Extension.

“We’re going to duplicate what we did for tunnel ventilation in this barn and shift away form soaking cows in the barn for cooling because we’re getting very concerned about water usage,” Brenner said. “We’ll soak cows in the holding pen, but when they come back to the barn we’re going to focus on wind speed.”

The goal is for the wind over the bunk where the cows are eating and over the stalls where the cows are lying.

“The basket fans provide very focused wind and the panel fans provide broad wind, but not the velocity,” Brenner said.

Some of the power for basket fans comes from the methane digester on the farm.

“For the tunnel fans, the two peak fans run 24/7 and 365 days a year,” Brenner said. “The lower fans are set on four thermostats and turn on as the temperature increases.”

The 925 Holstein cows on the farm are milked three times a day in a double parallel parlor.

“The cows are producing about 97 pounds of milk per day and the components are running at 4% butterfat and protein is in the 3.15% to 3.18% range,” Brenner said.

Crops are grown on just under 2,000 acres with corn on 1,100 of those acres.

“About 825 of those corn acres are harvested for corn silage and we have 400 acres of alfalfa which is all harvested as haylage,” Brenner said. “The goal is to take four crops of haylage off.”

The remaining acres are split between soybeans and wheat which is grown for straw.

“The only cash grain for us is the wheat,” Brenner said. “The soybeans are grain banked at our local feed mill, roasted and brought back to the farm for feed.”

Bedding in the freestalls is material after the digestion process is finished.

“As the cows go to the parlor to be milked, the manure is scraped to the center flume of the barn and the bedding in the stalls is prepped,” Brenner said. “We add fresh bedding to the stalls in the morning, four to five times per week depending on product availability.”

The key, Brenner said, is the dry matter of the material.

“I can get it to about 42% dry matter and if it stays in that range, it works very well,” he said. “The damp and cold times of the year during the spring and fall are the hardest times for us because the air is so heavy and wet.”

Manure flows from the barn to a collection pit and as the pit fills up, the manure is transferred to the digester.

“The digester has to be treated like a cow and if you feed it like a cow, it will give you a consistent product,” Brenner said.

“It is an anaerobic digester and the manure is in there for 28 days to kill all the pathogens that might have been in the manure and also to break down the fiber,” he said. “We have two products coming out of the digester — the liquid product is stored in the holding basins and taken to the fields to fertilize our corn crop and the dry material is the bedding for the cows.”

Since more bedding is made than can be used at the farm, Brenner sells the extra to a dairy farmer neighbor.

“I sell about 17 tons of bedding per week,” he said.

The digester needs to stay at 101 degrees for optimum performance.

“We have a boiler that’s methane powered so we’re firing the boiler with methane gas from the digester,” Brenner said. “The heat coils in the digester maintain the temperature at 101 degrees and we also have heat exchangers to heat our water for the dairy.”

Cover crops are important for the rolling topography on the northwestern Illinois farm.

“We take soil erosion very seriously so we take advantage of anything we can do to maintain soil placement,” Brenner said. “We do 100% cover crops on all the acres harvested for corn silage.”

Brenner has learned a lot about cover crops over the last three or four years and the crop that has been the most consistent is rye.

“We have changed the maturity of the corn varieties to try to get a good stand of rye established before the winter frost,” he said. “The last two years we’ve gone to 105-day corn and that made a huge difference.”

Currently, the dairyman does not harvest cover crops for forage since he does not have any heifers on the farm.

“You can use rye in a dairy cow ration if it is harvested correctly, but the window of opportunity is about three days to make milk cow feed,” he said. “If our system changes and we have our heifers on the farm that would be an opportunity to utilize the rye as a forage.”

Brenner works with Compeer Financial which provides him benchmark numbers to compare his operation with other dairies.

“Their team has a specific group that works just with dairies all over the Midwest,” Brenner said.

“Feed cost is one we’re always looking at and we try to be between $7 and $8 per hundredweight,” he said. “One thing we really focus on is trying to lock our commodities in because we don’t have a lot of control over milk price, but we have some control over feed cost.”

Brenner tries to make his purchases at least a year in advance.

“If you know you can lock your costs in at profitable level you need to do it,” he said. “If we were in the cash market right now we could easily be adding 50 to 70 cents per hundredweight in feed cost.”

The second most expensive cost on a dairy is raising heifers, Brenner said.

“We use to raise our calves from birth to six months of age, but we were frustrated with performance and we weren’t doing it as efficiently as it can be done in a different environment,” he said.

Therefore, Brenner made the decision to have his heifers raised by a custom grower.

“This has been very positive for us because it locked our costs in and we know what it costs to get a heifer from birth to calving,” he said.

In addition, since the heifers are off site, Brenner can set protocols to determine which females come back to the farm.

“If she is a hard breeding heifer, she’ll probably be a hard breeding cow,” he said. “So, this allows you to look at what’s important which is getting a profitable, productive animal to the milking string.”

Brenner sends his heifers to Kansas.

“We went and visited the farm and it’s an awesome facility,” he said. “It is a totally different environment than northwest Illinois.”

The dairy cattle are housed on a dirt lot with a cement feed pad.

“We can’t do that in Illinois because the climate and the regulations don’t allow it,” Brenner said. “But they can shave 50 to 60 cents per day off the cost with their facilities.”

In the future, Brenner said, he may look at building new calf facilities on the farm.

“We had too many heifers for what we needed,” he said. “And we saw that a lot of other dairies had their heifers custom raised.”