Raising heifers has changed over the years, and Penn State ag engineer John Tyson said there are still some new concepts in heifer housing.
“Calves and heifers represent the best genetic potential on the farm,” said Tyson, who spoke recently at the Penn State Dairy Nutrition Workshop. “That’s why we’ve picked bull semen, bred dams and kept the best genetics. What we do with genetic potential is worth money.”
Tyson said the goal of calf-raising facilities is to provide the environment and management to raise healthy, well-grown calves and heifers that are ready to enter the milking herd between 22 and 24 months. Well-designed heifer housing also includes a safe environment for the calf caregiver.
Genetics and feed programs have resulted in heifers that grow bigger and faster. Heifers are worth a lot of money, so it’s worth taking care of them properly. Tyson cited several publications about developments in heifer housing and said the goals are the same, but what’s different is the growth curve.
“In the early 1990s, we started to design housing around the 50th percentile,” said Tyson. “Today, for most heifers, it seems like the 50th percentile farms have ceased to exist. Heifers are getting bigger faster because we feed and manage them better. The publications weren’t wrong – we were in the wrong category or the wrong column of design.”
Faster-growing heifers means more feed, which also means more manure. “What goes in must come out,” said Tyson. “I’m seeing more manure produced from the same number of heifers.”
And as they grow, calves drink and eat more, which means more water vapor. As caloric intake increases, calves aren’t 100% efficient. But as calves consume more calories, there’s more waste heat to deal with through the ventilation system. “The same animals are producing more heat in a confined space,” Tyson said.
Animal housing groups have remained the same: baby calves, weaned calves, then several age categories for heifers. “Heifers didn’t come out of a heifer barn at 1,350 to 1,400 pounds,” he said. “They were 1,100 pounds if you were lucky, but it’s now routine to see much larger heifers.”
For calf pens, space is key. Tyson recalled the time four-by-eight-foot pens were considered a spacious calf pen. “We sometimes crammed them into four-by-six pens, and they did okay,” he said. “When we feed two to three gallons of milk in the front end, it has to come out somewhere. We wind up with more of the four-by-six pen that’s dirty and damp.”
Tyson now sees (and advises) dairy farmers to house calves in four-by-10 or four-by-12 pens. “We’re adding a considerable amount of square footage for individual pens, mostly because we’re adding more feed to get them to grow faster and perform better,” he said. “Group-housed calves are no different, whether they’re ad lib or auto fed. The number I’m using now is a minimum of 40 square feet, and 45 to 60 square feet works better for group-fed calves.”
Some new heifer barn designs are long and narrow, which Tyson said work well because calves prefer lying next to a solid wall.
When heifer calves are fed more milk and starter ration for optimum growth, it’s important to consider additional output and allow for extra cleaning to ensure dry bedding. Photo by Sally Colby
Transition calves include newly-weaned calves transitioning from individual hutches to a group or from a milk diet to solid or forage diet. Tyson said the key with this age bracket is maintaining small, consistently sized groups.
“Similar group size doesn’t mean the same number in the group – it means the same size animals,” said Tyson. “Once there are more than two to four weeks’ age difference between the oldest and youngest in a group, there will be calves that don’t perform well because they’re bullied by the bigger ones.”
Bedded pack group pens work well for transition calves. “If calves have come from individual housing, this is the first time they have to compete for feed and water, and that’s an environmental stressor,” said Tyson. “If they’re coming out of a group-fed milk pen, the transition isn’t as stressful, but they’re still going from a milk diet to a solid feed diet.”
There’s a need for more space in bedded packs. The standard per animal space allowance was traditionally 25 to 30 square feet, but for today’s heifer calves, bedded packs should have a dedicated resting area of 40 sq. ft./head and a dedicated feeding area.
The area around the feed bunk should not be included in the allowed square footage. Depending on weather, feed and water areas may require more frequent cleaning.
The bedded pack base can be either concrete or earthen. A concrete base provides better options for cleaning and disinfection. Solid walls are an important consideration too.
“They aren’t quite heifers yet,” said Tyson, “so cold breezes and excessive wind can affect them, particularly during colder times of the year.”
In winter, an open building for the back third to half of the pen with a solid divider provides good protection. Long, deep pens are more common now, and pens that are twice as deep as they are wide work well for ventilation. Bedded areas should be separate from the service alley.
While calves do well in cold weather, they can’t handle poor ventilation. Insulating bedding such as straw helps calves thrive in cold weather, and calf jackets should be used when necessary. In summer, sawdust is suitable bedding.
Tyson suggested a minimum of three inches of straw bedding under calves to isolate them from the floor. Nesting score is important for both wet and weaned calves. A nesting score of 3, which means calves’ legs are not visible when they’re lying down, is ideal in cold weather.
Group pens should be easily accessible for cleaning and working with animals. It’s especially important to have access to pens to remove wet bedding. Pen design can include gates to hold animals at one end of the pen during cleaning.
Calves require 18 inches/head of bunk space to allow all animals to eat at the same time without competition. One popular option is a trough attached to the front end of the gate for grain, with a hay feeder above the trough or between pens. Because this is the first time calves will have to compete for feed, slant bars are better than headlocks.
Water is critical for healthy calves, so be sure the water system is reliable, easy for calves to access and easy for workers to clean.
As calf buildings have become larger, more fans are required for adequate ventilation to dispel heat and moisture. “There’s really nothing new in the technology,” said Tyson. “It’s just getting in the right category.”
by Sally Colby
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