Many farmers rely on natural ventilation to provide clean and fresh air in calf barns. But in winter it can be difficult to balance fresh air with keeping calves warm. Many farmers close doors, windows and curtains to reduce drafts. But when buildings are closed proper air exchange to keep calves healthy can be challenging.

Proper ventilation and adequate air exchange can decrease the buildup of dust, pathogens and moisture in the air. That helps reduce the risk of calves developing pneumonia and other respiratory diseases.

A positive-pressure ventilation system brings fresh outside air into the barn and evenly distributes air. The system is designed to move air into areas where air may be stagnant such as between solid-pen panels. Stagnant air can harbor airborne pathogens, which may present health challenges to calves.

The goal for winter ventilation is a minimum of four interior air exchanges per hour. A well-designed positive-pressure ventilation system will deliver fresh air to calves without creating a draft. It can run 24 hours per day, even in cold weather. That alleviates seasonal limitations seen with natural and negative-pressure ventilation systems.

While positive-pressure ventilation systems can be a good solution for providing air exchange throughout the calf barn, they’re not “one size fits all.” A system should be designed based on number of calves, building size, barn dimensions and pen layout. There’s a fine line between providing adequate ventilation and creating drafts. Precise planning is needed to achieve even air distribution throughout the barn.

Doing one’s homework and working with an expert will help a dairy farmer determine the best fit for his or her farm. The Dairyland Initiative, a University of Wisconsin-School of Veterinary Medicine program, provides resources for planning a ventilation system.

Consider more calf care

Ventilation is a critical part of winter calf management. Help calves thrive during cool weather months with a complete management program.

  • Ensure each calf has 30 to 35 square feet of resting space.
  • Pack 5 to 6 inches of bedding between the floor and the calf.
  • Bed with deep, clean and dry straw in which calves can nestle.
  • Provide calf jackets as needed.
  • Use pens with an open front and back, with solid panels between.
  • Feed one-half pound to three-quarters pound more milk solids daily, recommended as a third feeding.

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