In testing at the University of Saskatchewan, this two-step weaning process reduced weaning stress on calves compared to traditional weaning methods. Here's how it works.
Read the follow-up article: More on two-step weaning process.
The best method of weaning calves may be the two-step. The first step involves preventing the calves (still with the cows) from sucking, while still allowing them to drink and graze. The second step is actual separation of the calves from their dams.
In testing at the University of Saskatchewan, this two-step process reduced weaning stress on calves compared to traditional weaning methods. That was the surprise development in a recent weaning study at the Western College of Veterinary Medicine in Saskatoon, Canada, designed to investigate the calf distress caused by traditional weaning methods.
Typically, weaning involves breaking up a cow/calf pair and moving each to a separate location. Both the cows and calves show dramatic behavior changes at this time.
Cows and calves spend lots of time and energy bawling and walking as they search for one another. As a result, they spend significantly less time eating and ruminating compared to before weaning.
Calves particularly show depressed performance following weaning. Many will get sick and need to be treated.
So last fall, we decided to find out whether calf distress at weaning was due to being denied milk or being denied the social and physical contact with their mothers.
To separate these two factors, we fitted half the calves with a device that prevented them from sucking their dams but still allowed them physical contact with their mothers. Calves could still eat and drink water while they wore the devices.
To our surprise, the calves prevented from nursing in the presence of their mothers behaved the same as the calf group still allowed to nurse. Both groups ate with the same frequency and walked the same amount, while vocalization and calling were essentially zero for both groups.
Once the anti-sucking devices were removed and all calves were separated from their dams, only the control calves (the traditionally weaned group) bawled and walked aimlessly. The calves that had been prevented from nursing for just a few days rarely called after being separated from their mothers.
In fact, the two-step calves vocalized 85% less, walked 80% less and spent 25% more time eating compared to calves weaned the traditional way.
The benefits are far more dramatic than those seen with fence-line weaning, which is in itself a big improvement over separating cow/calf pairs out of view of each other. In fence-line weaning, calves are physically separated from their mothers in adjoining pastures.
We believe that calves weaned by the two-step process are apparently less disturbed by the weaning process. This fall, we're using more than 600 cow/calf pairs to measure the effects of the two-step weaning technique compared to traditional weaning on the immunology, behavior and production response of the calves. The findings may have tremendous implications for the beef industry, especially if the immunological and production response of the calves is improved through such a simple management tool.
In other work leading up the two-step discovery, we explored other protocols that we hoped would reduce post-weaning stress.
We replaced mother cows with “trainer cows” (cows marked for culling) with the intent of helping calves settle down, go on feed sooner and help stabilize their social environment after separation from their mothers.
We found that newly weaned calves behaved the same whether or not they were kept with trainer cows. There was no benefit in the calves' performance, immune function or health if they were penned with trainer cows.
In another test, we split a group of cow/calf pairs in half. We then gave each group of cows the other group's calves following weaning.
Both cows and calves, however, searched for their own partner with little or no obvious benefit from the presence of familiar adults. We're now certain that newly weaned calves are searching specifically for their mothers and gain little comfort from familiar or unfamiliar cows.
Many producers follow the axiom that ‘out of sight is out of mind.’ They feel the physiological and psychological stress of weaning is reduced and recovery is sped up if cows and calves can't see or hear each other. Our research, though, suggests that cows and calves don't follow the same axiom.
This research showed the amount of time calves spent walking and the number of times calves called was significantly reduced when calves and their mothers could see each other across the fence.
Research at the University of California-Davis shows that, in addition to reducing the distress response, calves weaned by fence-line contact gained about 30% more weight than traditionally weaned calves in the 10 weeks after they were separated from the cows. But you need to make sure you have strong fences.
Our fence-line weaning observations suggest that for cow/calf pairs, the mere sight of each other is enough to reduce some distress at weaning. This suggests that the fuss at weaning mostly has to do with breaking the bond between the cow and calf.
However, calves weaned by the two-step method made no fuss when they were denied milk or when they were denied contact with their mother. This suggests that traditional weaning methods of removing both milk and mother at the same time cause undue stress on calves.
Joseph M. Stookey, Ph.D., is a professor and Derek B. Haley is a doctoral candidate at the University of Saskatchewan's Western College of Veterinary Medicine in Saskatoon, Canada. For more information, e-mail Stookey at firstname.lastname@example.org or Haley at email@example.com, or call 306/966-7154.
Read the follow-up article: More on two-step weaning process