Tube ventilation at one dairy helped significantly cut pneumonia and death rates
When calf and heifer specialist Emily Stammen visited an Ohio calf-raising operation last spring, she found sky-rocketing pneumonia rates, a 27% death loss and calf growth rates nearly a month behind normal.
Six months later, pneumonia incidences had disappeared and death losses had dropped to zero. Average daily gains among the young calves stood at normal rates.
The calves’ improved health is largely the result of better air quality in the barns, along with reduced stocking rates, Stammen says.
“Air quality sometimes gets pushed aside in calf care because there hasn’t always been a good way to check it,” says Stammen, who works for Land O’Lakes. “But now with new tools, it’s easier to stay on top of it.”
Stammen suspected that poor air quality, which allows airborne bacteria to accumulate, was responsible for the calves’ respiratory problems.
The Ohio facility houses 150 calves in the nursery barn and 120 in its transition barn. Both barns had previously relied on natural ventilation and top-down curtains on the east and west sides.
Stammen used an air sampler provided by Land O’Lakes to capture bacteria levels in the barns. Results from Dr. Don Sockett at the Wisconsin Veterinary Diagnostic Laboratory revealed extremely high levels of bacteria. The desired level is 20,000 colony-forming units per cubic meter (cfu/m3) of air. Instead, the barn’s counts showed levels of 60,000 to 100,000 cfu/m3.
Increasing air flow to reduce airborne bacteria seemed to be a good answer-and tube ventilation was one way to achieve it.
With Stammen’s input, the calf operator installed tube ventilation in the transition barn to bring in small amounts of fresh air. The 24" diameter tube is 117' long, and bears 3" pre-punched air holes along its sides. It runs high across the length of the calf barn. A continuously running 16" fan mounted on an exterior wall draws outside air into the tube. To also reduce airborne bacteria, the calf raiser reduced his stocking rate to 14 to 16 calves per pen versus the previous 25 to 30 calves.
The operator’s decision to end the continuous flow of animals in and out of barns helped significantly. Leaving barns empty for one to two weeks now allows time to clean and air the barns before restocking them.
From March to July, when the facility’s respiratory problems were at their peak, the operation lost more than $20,000 in animal value and spent $5,000 in treatment costs. Since the changes were made, the operation “is actually making money and spending very little on treatment,” Stammen says. DT
Reduce risk
- Poor air quality allows airborne bacteria to accumulate in calf housing.
- Tube ventilation can reduce pneumonia incidences from 80% to less than 20%.
- For basic recommendations, go to: www.vetmed.wisc.edu/dms/fapm/fapmtools/9ventilation/natural_vent_calf_barn_recommend_2006.pdf.
