SENECA FALLS, N.Y. — Calf needs vary from adult cow needs in numerous ways, including ventilation. Curt Gooch, senior Extension associate with Cornell Department of Animal Science, presented “Calf Housing Ventilation: What’s the Latest?” at the recent Empire Farm Days.
“The calves are our future lactating animals,” Gooch said as he encouraged attendees at the Dairy Profit Seminar to pay attention to the smallest members of the herd.
He added that many dairy farms’ dairy replacement animals include newborns (birth to 10 days post-weaning), transition calves (post-weaning to 400 pounds.) and adolescents (400-1,200 pounds). The very youngest animals are the most susceptible to issues caused by poor ventilation.
Calf ventilation is a big part of calf care, which Gooch counts as important since “calves are born with no immunity,” he said.
He includes ventilation right along with nutrition, clean water, proper resting area, pathogen control and observation by a caretaker.
He believes that improper ventilation can stress calves, especially during changes in weather during fall and spring.
“Weather can be tough on calves,” Gooch said.
But even ideal temperatures can stress calves if the ventilation in their barn or hutch isn’t ideal. He has observed a newborn calf shivering in a barn in the middle of a summer day because the still-wet animal laid in a draft, for example.
Gooch likes calf hutches’ freedom of movement that allows animals to stay inside, lie in the sun, rest in the shade of the hutch or use any combination of those options they want. The calves can seek whatever is comfortable for them.
“In barns, we take away a lot of the choices for them,” he said.
Correct ventilation can improve calf comfort. It includes aspects of the facility design, protocols and management and maintenance. Design basics are fresh air coming in and mixing with stale air inside.
“We can never over-ventilate a cow or calf barn, but we can over-spend and we can create drafts,” Gooch said.
Draft occurs when the air speed is greater than 98 feet per minute for calves younger than 12 weeks.
Natural ventilation is whatever openings occur in a structure. Natural assisted and mechanically assisted refer to structural changes to improve ventilation. Mechanical ventilation is all about positive pressure, negative pressure and neutral pressure strategies to move air through the barn.
When considering natural ventilation, site selection, building orientation, adjustable sidewalls, adjustable end walls, eaves and ridge openings all affect the internal temperature and air quality. Gooch said that managing these barns is more difficult, especially for larger structures. Solid partitions between pens means that air can be restricted among animals.
He added that mechanical ventilation systems can offer solutions if the barn lacks consistent breezes, it’s larger than 35 feet and the operator wants a warm barn.
He encouraged operators to control air exchange at “calf nose level,” which is much lower than cow level.
Gooch also cautioned about manure gases in dairy barns.
“Some are heavier than air and some are lighter than air,” he said, referencing hydrogen sulfide and ammonia, respectively.
Calves’ small stature exposes them to hydrogen sulfide if it’s present and trapped in their barn.