The common challenging piece of grouped housing systems is respiratory disease. The question producers ask is, how to reduce and/or prevent it? Because the feeding equipment enables multiple meals and provides increased nutrition to the calf, the resulting calf is larger. This, after all, was the original goal. But this higher level of nutrition results in higher volumes of fecal waste and urine, thus higher moisture and ammonia levels in groups. Also larger calves produce higher levels of moisture in the air via respiration.
In order to help improve the pen environment, drainage of the bedding pack is vital, notes Denton. This may involve multiple cleanings and rebuilding of the pack prior to a group being weaned and moving out of the pen. The recommendation is 30 to 40 square feet per calf on the pack. This does not include the area where calves feed. Since the goal is larger calves, it is best to provide for the higher square footage so when calves approach weaning age you have adequate pen space.
The capstone of the entire system is the ventilation system in the group facilities. The use of positive air tubes enables the best year round ventilation. This system brings in outside air and distributes the clean fresh air at a speed that does not create a draft or cold stress on the calves.
Another challenge is viral disease transmission via a common nipple. Be mindful, a calf’s mouth and muzzle is the equivalent of a human’s hands. Calves touch and lick everything in their environment. Calves frequently lick their own nose. A calf that has just licked its own nose goes to the common nipple and feeds – thus contaminating the nipple for the next calf. “We humans are constantly reminded to wash our hands to prevent the spread of disease. We cannot wash a calf’s muzzle, but we can wash the item they use frequently – the milk nipple,” advises Denton.
Now, let’s look at weaning calves in the two systems. “Keep in mind that a minimum of two pounds of starter daily, per calf, for three consecutive days is the trigger to wean a calf,” reminds Denton.
Auto-feeders allow for greater ease to wean calves. The ability to program the availability of milk for calves on an individual basis allows for the “dialing down” of milk over a series of days to promote starter intake. Conversely, an ad-libitum system does just as it is called - feeding ad-libitum. Because the system feeds “the group” one must plan to wean “the group” based on the age of the youngest calf in the pen.
“Prior to moving towards group housing, it’s important to take aspects of each system into consideration,” says Denton. “Think through your needs not only today, but also what they might be in the future too.”