Research shows calves exposed to fence-line separation gained better in the first 10 weeks than abruptly weaned calves
Weaning is stressful on calves, and multiple studies show those that are abruptly weaned often struggle with respiratory disease and require treatment.
Many of these calves have been recently separated from their mothers, handled, processed and shipped to a feedlot where they are exposed to new feed and animals.
The 2017 Western Canadian cow-calf survey showed 49 percent of producers wean abruptly, while 34 percent do fence-line weaning and 11 percent practise two-stage weaning. By comparison, the last survey in 2014 found about 70 percent used abrupt weaning while 22 percent used fence line, six percent tried two-stage weaning and the remainder used natural weaning.
Fence-line weaning separates cows and their calves with a fence, but they can still hear, see and smell one another. Some may have nose to nose contact.
Research by Derek Haley of the University of Guelph showed calves exposed to fence-line separation bawled less, walked less and gained better in the first 10 weeks of weaning compared to abruptly weaned calves.
In a paper from the Beef Cattle Research Council, researchers found good facilities and adequate water supplies for cows and calves are needed to facilitate that process.
To set it up:
- In the pasture, lock the cows in the corrals and leave the calves loose in a familiar environment.
- Set up page wire in the pasture and sort cows from calves onto either side.
- Separate cows into a neighbour-ing lot.
- Pen size can be adjusted to reduce space available for calves to walk. Smaller pens allow calves to find feed and water and reduce the potential for dust problems. This can be done by setting up temporary panels and cutting the pen in half. After a few days, remove panels so the calves can spread out.
Fence-line weaning is not perfect, but it is an improvement over abrupt separation, research indicates.
Calves seem to settle down, but it is not as good as two-stage weaning, said Joe Stookey, professor emeritus at the University of Saskatchewan.
He and a team of researchers evaluated different forms of weaning and found two-stage weaned calves seemed calmer and ended up healthier.
“The results are plain. One group of calves is lying down and ruminating and the other group is pacing and bawling. It is night and day in how they act, and that behaviour translates into stress and reduced immune function and sickness,” Stookey said.
Researchers at the Western College of Veterinary Medicine in Saskatchewan experimented with two-stage weaning with reusable nose flaps. These plastic tags are inserted into calves’ noses to prevent them from nursing for a few days before separation.
Derek Haley, who now works at the University of Guelph as a professor in animal welfare and behaviour, was part of that research.
In an email, Haley said a common mistake is taking the nose flaps out and leaving the calves with their mothers. The calves must be separated from the cows after removing the devices.
The flaps can stay in for about four days. There is no advantage to leaving them in longer than seven days.
“We discourage people from leaving them in for longer,” he wrote.
Current research focuses on offering creep feed to the two-stage calves wearing nose flaps to ensure their nutritional needs are met.
“Reducing the stress of breaking the cow-calf bond is only one part of managing calves at weaning, and we need more work done on how to take the best advantage of those calves that are less stressed, to maximize their gains at that time, which is the point in time when we know abruptly weaned calves are off feed and losing weight,” Haley wrote.
With conventional weaning, cows and calves are upset and start walking in search of one another. Researchers wondered if the calves needed milk or their mothers.
The conclusion was that they wanted their mothers, said Stookey.
Conventional wisdom said weaned calves struggled because they did not know how to eat.
“That is bunk. What they are doing is spending three days trying to relocate Mom. The two-stage weaned calves, when we separate them from Mom, they just go on eating. They know what food is,” Stookey said.
Besides work on nutrition, more research is needed to assess cattle health after two-stage weaning.
“We don’t have the health data, which is what we need to finish the story,” said Stookey.
Cattle are usually treated with broad spectrum antibiotics upon arrival at the feedlot on the presumption some will get sick.
“Calves that are prepped, calves that are vaccinated, calves that are on feed, they are very low risk calves,” he said.
“These calves that are coming through two-stage weaning are not at as a high a risk.
In contrast, freshly weaned calves are at higher risk upon entry in a feedlot.