Though seldom viewed through the same prism, the breeding and management decisions that add up to weaning performance are the same ones that add to cattle welfare. Consider deciding which bulls to breed to which cows.
“Since about 1960, the beef industry has done a brilliant job of improving cow mature size as well as the genetic potential for milk production, all in the name of larger weaning weights that we hope will be more profitable,” says K.C. Olson, a cow-calf nutrition and management specialist at Kansas State University (KSU).
There are costs to such success, though, both in terms of cattle welfare and weaning performance.
First, calf dystocia increases as birth weights increase. And, increased dystocia is one of the causes of failed passive transfer (FTP), the lack of antibody protection passed to calves by dams through colostrum.
According to research, Chris Reinhardt, KSU Extension feedlot specialist, says calves that receive inadequate passive immunity are:
- Six times more likely to die within the first 28 days of life,
- Three times more likely to get sick at some point before weaning,
- Five times more likely to die before weaning and
- Three times more likely to get sick when they get to the feedlot.
Reinhardt and Olson were among presenters at the International Symposium on Beef Cattle Welfare (ISBCW) in May, hosted by the KSU Beef Cattle Institute.
Another cause of FTP is inadequate body condition of the cow heading into calving season. According to Reinhardt, cows with a body condition score (BCS) less than 5 give less colostrum, and the colostrum they do produce contains less immunoglobulin than cows with more body condition. Cows with a BCS of 4 or less have less stamina during and after parturition, while cows with a BCS of less than 4 have calves that possess less energy for parturition.
Bottom line, cows with a BCS less than 5 produce calves with a lower survival rate. “We can plot calf survival as we click down through levels of cow body condition. It’s a welfare issue,” Reinhardt says.
Matching cows’ nutrient needs to forage quality and availability is important, the specialists say.
“Grazing management is really where nutrition starts; it’s where animal welfare begins on a cow-calf operation,” Olson says.
And, the optimal stocking rate that enables effective grazing management begins with utilizing cattle that fit the environment.
“For every 200 lbs. that we add to mature cow weight, we add about 20% to the cow’s maintenance requirement,” Olson explains. “When we add 10 lbs. of milk production potential to the cowherd, we add about 20% to the maintenance requirement.”
In return, added mature size and milk production aren’t necessarily returning more weaning weight. Using 2008 data from the Cow Herd Appraisal Performance System (CHAPS), Olson explains, cows weighing less than 1,200 lbs. weaned calves that weighed an average of 617 lbs. at weaning. Cows weighing more than 1,600 lbs. weaned calves at an average of 434 lbs.
“What we effectively do as an industry is put large, heavy-milking cows in an environment that is nutrient limiting and ask them to perform to their genetic potential, and they simply can’t do it,” Olson says. At least not without supplemental feed.
Small cows are not equivalent to efficiency, or vice versa. Olson’s point is that when genetic potential is ineffectively matched to resources and management, weaning performance suffers, and animal welfare suffers.
Besides ill-matched genetics and environments, Olson explains that subpar nutrition or malnutrition also occurs when stocking rates are too heavy or too light, and when the production cycle is poorly conceived for the environment.
Stocking rates determine the quality of forage that cattle have the opportunity to consume. When it’s too light, plant growth exceeds cattle defoliation, allowing plants to become reproductively mature and less nutritious. If it’s too heavy, cattle are left only the less nutritious basal portions of the plant to consume.
As for the production cycle, think in terms of peak nutrient availability, relative to cows’ peak nutritional needs.
Using Kansas as an example, most producers gear cows to calve in February and March in the name of the heaviest weaning weights. But, in this scenario, forage nutrition is poorest when cow nutrient requirements are highest at peak lactation.
“In Kansas, native warm-season forage is adequate or marginal nutritionally from about May 1 to the end of the calendar year to meet cows’ nutritional needs,” Olson explains. “From January 1 to May 1, the nutritional character of native warm-season forages is well below what is required to support calving and early lactation. We usually fill that nutritional void with a great deal of harvested forages and some supplemental concentrates.”
Simply moving the calving season from February and March to April and May means that cow nutrient requirements will be minimal when forage quality is poor. The nutrient requirements of the cow peak as the quality of the forage peaks.
Such a system means weaning a lighter calf, but Olson says there are more than enough cost savings in feed, fuel and equipment depreciation to make up for the deficit in weaning weight. Plus, calves come into the world without experiencing the harshest part of winter.
Calving in tune with Mother Nature also simplifies managing cow body condition, according to Olson. Since KSU moved its calving season later into the year, he explains, “Our cows are weaning a 150-day-old calf that weighs 500-550 lbs. in early October and ending lactation with a BCS greater than 5.”
Incidentally, KSU also culled hard the past four years to reduce average mature cow weight in its herd from 1,350 lbs. to under 1,200 lbs. For their 400-cow herd, that’s 60,000 lbs. fewer, and 50 fewer cows (basis 1,200 lbs.) grazing the same resources. “The most immediate benefits have been in improved range condition and improved cow-body condition. We think we’re seeing increased cow longevity, too,” Olson says.
The same resource matching extends to when calves are weaned relative to forage quality and availability. Again, using Kansas as his example, Olson explains that the traditional weaning month of November (and a traditional February-March calving season) means calves are still suckling when forage quality is inadequate to support lactation. “The cow must mobilize significant body reserves to continue producing,” he says.
“If we end cow lactation 60 days earlier than normal, (Sept. 1 rather than Nov. 1) we go from having a forage base that’s marginal in meeting the cow’s nutritional needs to one that significantly exceeds her needs,” Olson explains. “We prevent the drastic loss of body weight that typically occurs among lactating cows in October and November (typically 100 lbs. during the last 60 days of lactation).” He defines early weaning here as at 150 days rather than the traditional 210 days.
Benefits of reducing calf stress
All this is before considering the stress of dehorning and castration. Research agrees that the earlier in life these are performed, the less stress there is on the calf, Reinhardt explains.
And, that’s before considering the stress of weaning itself, which represents the most traumatic and stressful time in cattle life, says Joseph Stookey, from the Western College of Veterinary Medicine (WCVM) at the University of Saskatchewan, Canada. He was also a presenter at the ISBCW.
“I wish we could go back in time and rename shipping fever,” Stookey says. “It’s not shipping fever, it’s weaning fever.” He explains experience and science are clear that weaning calves at the same time they’re shipped results in more calf stress and calf morbidity. Until recent years, what’s been less clear is how to make the weaning process less stressful.
Though ranchers may have already discovered it, animal scientists never took a hard look at fenceline weaning until the 1990s. Rather than remove calves from their dams and separate them geographically (abrupt weaning), fenceline weaning involves separating dams and calves by a fence. Though calves are separated and can’t nurse, calves and dams are allowed nose-to-nose contact across a common fence during the process.
Compared to abrupt weaning, fenceline weaning results in calves and cows that vocalize and walk less, and rest and ruminate more. It has proven to be significantly less stressful than abrupt weaning.
Stookey and his peers at WCVM dug deeper into why it was less stressful. Long story short, they wondered if removal from either the cow or the milk was the most stressful part of weaning. That ultimately led them to leaving calves with their mamas, but attaching an anti-suckling device (see photo on page 23) to the calves so they couldn’t nurse (except for a few industrious cheaters). The result is what is now known as two-stage weaning. Consider one study that compared abrupt-weaned calves with those weaned via the two-stage method. Calves weaned abruptly walked as many as 20 miles/day for the first two days after separation, compared to five miles for calves weaned with the two-stage method.
“That takes a lot of energy to call and walk 20 miles,” Stookey says. “No wonder they get sick.”
Two-stage weaning also results in significantly less stress on calves when compared to fenceline weaning.
Regardless of the method, Reinhardt says weaning and preconditioning needs to be about more than making sure the calves are vaccinated.
“They need to be prepared for the stress of weaning and shipment,” he says. “They need a period of separation between the stress of weaning and the stress of shipping, and I feel the period of necessary separation may be proportional to the shipping stress the calf will face.” As an example, a calf moving two pastures away will likely face less stress than one embarking on a 1,500-mile trailer ride.
Aside from the performance gains such attention to cattle welfare can make possible at the ranch, Reinhardt says, “Really, it’s becoming an obligation for producers to help prevent cattle sickness from occurring in other industry sectors by how we prepare calves at the ranch.”