MINNEAPOLIS — Social housing is the future for raising dairy calves.
“From 70% to 75% of the calves in the U.S. are housed individually during the pre-weaning period but that’s changing,” said Whitney Knauer, DVM and assistant professor in the College of Veterinary Medicine at the University of Minnesota.
“I’m a big proponent of pair housing because I think it’s an easy shift from individual housing, but there’s some advantages to small groups,” said Knauer during a webinar hosted by Hoard’s Dairyman.
To care for calves, the veterinarian said, dairymen want a system that’s economical and labor efficient that results in a healthy calf with a high potential for longevity in the herd.
“Calves want good health throughout the pre-weaning period and they crave socialization early in life,” Knauer said. “They want to be free from fear, stress and pain.”
“I think for the benefits to the producer and calf, any sort of social housing wins as compared to individual housing,” she said. “If social housing is not possible during the pre-weaning period, you should be finding ways to socialize calves prior to grouping at weaning.”
At weaning, dairy calves can experience stress from nutrition, environmental or social changes.
“If we can take the social stress away, they will have potentially better health in the post weaning pen,” Knauer said.
“Social housing exacerbates problems or challenges already present within the system so we need to be doing a good job before we make the switch,” she said.
Studies show pair housing improves pre-weaning growth of calves.
“I followed calves to four months of age and at weaning we had an 18-pound difference in body weight in the paired calves versus individually housed calves and a 17-pound advantage in paired calves at 16 weeks,” the veterinarian said.
Knauer talked about two studies that showed the paired calves have improved starter intake.
“At five and six weeks, the paired calves are eating much more starter than individually housed calves,” she said. “And this similar study showed paired calves at eight and nine weeks are eating much more grain compared to individually housed calves.”
Knauer put activity monitors on dairy calves to evaluate their behavior.
“Seven days prior to weaned pen entry the calves were doing pretty much the same thing, laying down and resting for 18 hours,” she said. “But on the day they moved to the weaned pen there was a big difference.”
All the calves decreased in their lying time, the veterinarian said.
“The previously paired calves laid down for three more hours that day compared to the individually housed calves and that persisted for six days post wean pen movement,” Knauer said.
“We also looked at social adjustment which is something that’s really hard to measure,” she said. “We used whether the calves are grooming each other as a proxy for how socially adjusted these calves were.”
The researchers found the paired calves were socially grooming 14% of the time, but the individually housed calves only 3%.
Knauer identified some best management practices for dairymen who switch to pair housing calves.
“Calves should be paired sometime in the first three weeks and ideally there should be no more than 14 days between calves in a pair mostly due to starter intake and growth,” she said.
Each calf should have at least 35 square feet of resting space.
“Two hutches for two calves or if they are in a barn two spaces for two calves,” Knauer said. “After the first week of life, calves start hanging out together in the same hutch between 60% to 80% of the time.”
Cross sucking — which Knauer defines as sucking any part of the calf — becomes a problem when calves are sucking on other calf navels or udders.
However there are tools to prevent this behavior, Knauer said.
“Before milk feeding very low cross sucking happens, but after milk feeding there’s a lot of cross sucking and the majority is happening in the first 10 to 14 minutes after milk is fed,” she said.
Therefore, one of the strategies is to feed a high milk allowance of at least six liters of milk per day or the equivalent of 1.8 pounds of dry matter.
“If we can keep the calves occupied and nursing, that will reduce their desire to cross suck,” Knauer said.
“Another strategy is to feed milk through a nipple bottle or bucket,” she said. “You can also provide a barrier between calves at feeding time.”
Each calf should have its own starter and water bucket.
“We want to offer them multiple opportunities to drink water and eat starter,” Knauer said.
“I think a lot of these principles translate to small groups,” she said. “But we still need some more producer experience and studies to look at the advantages and disadvantages for the best number of calves — there’s a lot to learn.”