Calf hutches and individual pens have long been credited with improving calf health and preventing the spread of pneumonia and other contagious diseases. They’ve worked so well, in fact, they (and sexed semen) are sometimes blamed for the glut of heifers that now populate America’s dairy farms.
But emerging research suggests individual calf hutches or pens might actually be inhibiting the social and cognitive development of young calves. That’s critical to calves when they are weaned, comingled with other animals and forced to adapt to new pens, feeding and watering systems, barns, and environments, says Jennifer Van Os, an animal welfare Extension specialist at the University of Wisconsin.
“Two heads are better than one in being flexible and adapting to new things,” she says. “Paired calves have increased dry matter intake and increased weights.”
Van Os points to research at the University of British Columbia which shows that individually housed calves are more fearful of new things, including new feed. So the sooner you pair calves up, the better. “Reduced fear with new feed items translates to better intakes and then better weight gain,” Van Os says.
UBC researchers paired calves at one week and six weeks, and found the earlier paired up calves do better. But even if paired at six weeks, the paired calves tended to do slightly better than calves housed singly through weaning. By 10 weeks of age, the early-paired calves were consuming about 7 lb/day of solid feed dry matter. The late paired calves were consuming about 6 lb/day of solid feed dry matter and the singly-housed calves about 5.5 lb/day, though this difference was not statistically different.
The earlier paired calves had an average daily gain of about 2.4 lb during weaning between 6 to weeks of age. The late paired and single calves gained less than 2 lb/day during weaning. Van Os notes that pre-weaning bodyweight gains predict future productivity, especially first-lactation milk yields.
The paired calves also had less than half the number of vocalizations at weaning, indicating lower stress levels. And it took singly-housed calves nearly 50 hours to find feed when moved to group pens after weaning. The paired calves took about 9 hours to find feed.
“The researchers found that the paired calves spent 34% more time per day at the starter feeders, visited the feeder 58% more often, and ate 50% more starter than the singly-housed calves,” says Van Os. All that combined to improve feed intake for the critical first two weeks after weaning for the paired calves.
One objection to pairing calves is lack of space or facility design. But Van Os says pairing can be as simple as pushing two hutches close together and then bending calf panels or woven wire around the front of each to form a small, single pen
Pairing calves is not without risk, she notes, including increased disease and cross sucking. But if calves are healthy and eating well before pairing and are provided clean, dry housing, those risks should be minimal.