Group rearing of calves gaining traction

About six years ago, Countryside Verinary Clinic in Lowville, N.Y., invited Canadian veterinarian and researcher Neil Anderson to be its guest at a producer meeting. Anderson was pioneering a new method of rearing dairy calves that he had learned from colleagues in Finland: housing calves in groups and feeding them from bulk units using “acidified” milk that was preserved with formic acid.

Countryside veterinarian Mark Thomas was intrigued with the process, but not necessarily eager to embrace it. But the next morning, a client named Jon Beller from Beller Farms near Carthage, N.Y., called to say he wanted to try it. “I said, ‘Jon, no, I don’t think you want to do that. I’m not really sure it will work,’” Thomas recalls. But the young dairyman persisted, and today he and several other Countryside clients are using the system, with great success. Thomas is now a believer, too.

After decades of raising calves in single-unit housing systems and feeding them individually, many U.S. dairy producers are seriously considering switching to group rearing as a viable alternative to raising healthy calves, while reducing the amount of labor it takes to do so.

The benefits of “nature’s way”
While critics worry about the potential for communicable disease and cross-sucking among heifer calves in group housing, proponents say it provides calves a more natural upbringing, both socially and nutritionally.

The adoption of group rearing systems dovetails with another current change in calf-raising philosophies: feeding calves on a higher plane of nutrition to more closely mimic the intake that would occur if they nursed their dams full-time. Mike Van Amburgh, dairy scientist at Cornell University, has explored the accelerated feeding approach extensively. He says the studies that have looked at the lifetime productivity response to increasing nutrient intake prior to weaning show an average increase of more than 1,700 pounds in first-lactation milk yield.

While it is possible to deliver enhanced nutrients via individual-bottle feeding, that task is made much easier in group housing, in which calves have more ready access to liquid nutrients around the clock. Anderson says group housing and feeding reduces hunger in calves, eliminates gorge feeding, keeps abomasal pH levels steady, and promotes social behavior among calves, supporting their natural herd instincts.

Compared to conventional feeding systems in which calves are fed two or three meals per day, Anderson says free-access-fed calves average seven meals per day which last seven minutes each, for an average of 49 minutes of suckling per day. Daily intake when calves are allowed to nurse ad libitum usually falls in the range of 8 to 12 quarts. He says his behavioral observations — and those of his Finnish colleagues who have been group-feeding for more than a decade — are that the regular presence of nipples and a milk supply satisfy the biological need to suckle. Thus, cross-sucking of ears and navels is rarely a problem.

And, contrary to what might be expected, those familiar with group housing also report fewer health problems in group-fed calves. They theorize that calves’ improved nutritional status helps support immune function and keeps digestive-tract processes more steady. In a recent Cornell study, calves on two separate nutrition programs were evaluated for their response to experimentally induced cryptosporidium infections. The group fed more nutrients had faster resolution of scours, grew better and had more efficient feed conversions than the group on a more conventional diet.

Automation promotes consistency
While most of Anderson’s experience with group housing is with feeding acidified milk or milk replacer, another method growing in popularity is automated feeding systems. In less than five years on the U.S. market, about 400 of these units now are operating, estimates Jim Fisher, a calf care consultant with GEA Farm Technologies, Inc., one of at least three companies marketing the automated feeder technology in the United States.

The computer-based, automated system eliminates one of the key concerns about group housing: detecting timid or sick animals that may not be receiving their full share of nutrients. Every animal is equipped with a computerized ear sensor chip or neck tag that signals which one of four possible, customized rations it is to be served. The volume of milk or milk replacer allowed per 24 hours (usually 6 to 8 liters) also is controlled for each calf, so dominant animals cannot consume nutrients intended for others. Individual or group medications can be delivered via the feeder. The temperature and concentration of the liquid ration are consistent with every feeding, and computer records show consumption for each animal, as well as drinking speed.

“We can tell from the monitoring records that a calf has slowed down consumption 24 to 36 hours before it begins to show visible signs of illness,” says Fisher. “This early detection and treatment opportunity allows us to stay ahead of health issues and keep calves consuming and gaining consistently.”

While some dairies are building dedicated facilities to house the new units, “about 75 to 80 percent of the units we have installed so far have gone into retrofitted barns,” he shares. That can work just fine, he says, as long as ventilation is excellent and free-choice water is available at all times. One of the most distinct changes Fisher notices in auto-fed calves is their disposition and social behavior. “Auto-fed calves are very calm and mellow,” he says. “They are rarely bawling, and don’t walk up and start sucking a person who walks into the pen, because they are not hungry, and they don’t associate humans with being fed.”