Pinpointing the exact cause of lameness in feedlot cattle could be a challenge, says beef science expert
Losing the feed additive Zilmax isn’t a big deal in the short term, but losing a product known as “Vitamin Z” would have a huge impact, and reach far beyond the feedlot sector, says the science director for the Canadian Cattlemen’s Association’s Beef Cattle Research Council.
“Not having access to these tools doesn’t just impact the cattle feeders, it impacts society,” said Reynold Bergen.
Drug maker Merck has temporarily taken Zilmax, a type of compound called beta-agonist, off the market after Tyson Foods said it would no longer buy cattle given the growth promoter. Tyson said it was concerned it was the cause of mobility issues seen in cattle arriving at its plants.
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Merck is suspending Zilmax sales until it investigates the situation, but Bergen said that lameness in finished cattle could have a host of causes — such as laminitis, foot rot, or transport injuries.
“It could be related to a lot of other things besides Zilmax,” said Bergen, adding that it will be “a challenge” for Merck’s investigators to pinpoint the cause.
The larger question, he said, is whether society wants the cattle industry to give up the hormones, implants, and feed additives such as beta-agonists that — along with improved genetics — have greatly improved productivity. Without them, it’s estimated the Canadian herd would have to grow by 10 per cent to produce the same amount of beef. That would mean using 10 per cent more land and feed, plus other inputs, said Bergen.
“We’d also need seven per cent more fuel, seven per cent more fertilizer, and the cattle would produce 10 per cent more manure and greenhouse gas emissions,” he said.
But the general manager of the Manitoba Beef Producers said he’s not expecting a consumer backlash against beta-agonists.
“They are safe to use. I have confidence in our regulatory approval process,” said Cam Dahl.
The Tyson ban, which he described as a marketing decision, is unlikely to depress prices, he said.
“With the lowest cow herd in North America since the 1950s, there’s no threat of excessive supply at the moment,” said Dahl.
Bergen added the average consumer tends to focus on price — not production protocols — when purchasing beef.
“If we went backwards because people didn’t trust the registration, surveillance and food safety process and raised beef the way our grandfathers used to do it, we’d need to make a choice,” said Bergen.
“We have more people, but not more resources. That’s where feed efficiencies come in.”
While a drop in beef productivity would limit supplies, it wouldn’t necessarily mean higher prices for cow-calf producers because it would also hurt the profitability of feedlots and their ability to buy cattle, both men said.
“If feedlots are operating on an economically sound footing, they tend to spend their money on calves,” said Bergen.
Canada’s top two packing companies, Cargill and JBS plan to continue buying Zilmax-fed beef.
Industry sources have said that many feedlots will likely switch over to Optaflexx, a ractopamine-based alternative to Zilmax’s zilpaterol, that is considered to be a milder beta-agonist with a lower impact on weight gain.