Focusing on Ventilation.
Temperature fluctuations during winter tend to present challenges for calf raisers across the Midwest and many farms will see an uptick in respiratory issues. More calves are being raised in barns or other housing with greater protection from the elements and these structures rely on natural ventilation to provide clean, fresh air to the calves. This works well in the summertime; however, as doors, windows and curtains are closed in the winter, providing sufficient air exchanges to keep calves healthy can be challenging.
With the option of either mechanical or natural ventilation, the end goal is to provide fresh, clean, draft-free air at the calf level throughout the housing facility. Proper ventilation means taking outside air and evenly distributing it throughout the barn. The goal of your ventilation system is to control heat and moisture within your facility and remove other gases and pollutants. In the winter, the focus needs to be on controlling and removing excess moisture produced within the barn. Generally, the cold temperature within the barn is not what is affecting your calf health during the winter, it is the damp and wet air. Calves are constantly producing water vapor as they breathe. Researchers at Penn State University estimate that at 37 degrees, a calf produces 1.25 ounces of water per hour. While this may not seem like much, it equates to almost 2 pounds of water per calf per day that needs to be removed from the barn. Multiply that by how many calves you house within your barn and you end up with quite a bit of excess moisture.
If air within your barn is not constantly replaced with fresh outside air, this moisture can begin to condense on surfaces such as the floor, ceiling, and calf pens. This additional moisture can create an ideal environment for pathogen growth and lead to disease outbreaks and transmission. The goal for calf barn ventilation in the winter is to have a minimum of four air exchanges per hour. Good ventilation not only provides the needed air exchange, but it also provides good air distribution throughout the barn. This can be a struggle with the lower ventilation rates, leading to areas of the barn with air that is stale and wet while other areas have good air quality.
Proper air distribution can be provided by a positive pressure ventilation system. A well-designed positive pressure system will deliver fresh air at the calf level without creating a draft. For mechanically ventilated calf barns, work with the consultant who designed the system to stage the fans for adequate air exchanges depending on both the indoor temperature of the barn and the outdoor temperature.
Other steps you can take to keep your calves healthy through the winter are proper nutrition, using calf jackets, and frequent cleaning and removal of soiled bedding. Proper nutrition needs to be provided to calves in the wintertime as more calories are needed for maintenance. Calf jackets will help calves retain the body heat they produce. Clean, dry bedding and management is needed to provide insulation as calves will nest into the bedding in cold temperatures. Frequent cleaning and removal of soiled bedding can be an effective method to keep air fresh and reduce ammonia concentration, and clean, dry bedding is needed to provide insulation as calves will nest into the bedding in colder temperatures.
Focusing on ventilation in the winter months can result in improved health and performance of calves. Contact your Premier nutritionist today for guidance on improving ventilation in your barns.