Consumers often ask what is in the food they eat, and for good reason.

But when it comes to milk, they can rest assured there are two things that are not in what comes out of the gallon jug they pour into their glass or onto their cereal — antibiotics and recombinant bovine somatotropin.

While farmers sometimes use antibiotics to treat cows that are sick, they are required to keep the milk from those cows out of the bulk tank until the antibiotics have cleared out of the cow’s system. If that milk does reach the bulk tank for some reason, there are checks and balances in place to make sure the antibiotic-tainted milk doesn’t reach the food chain, according to Steve Ingham, administrator of the Wisconsin Department of Agriculture, Trade and Consumer Protection’s Division of Food and Recreational Safety.

Every tanker is tested

“Every tanker is tested and a sample is taken at every farm,” Ingham says. “For years there has been a rigorous antibiotic residue program and that hasn’t slacked off at all. We’re doing our job. Milk is safe to drink.”

When antibiotic residues are found in a truckload of milk, the whole load has to be dumped, Ingham says. In that case, the farmer responsible for the tainted milk would be liable for all the milk in the truck, even if some of it came from another farm.

Last year, 59 truckloads of milk tested positive for antibiotic residues in Wisconsin. That was down from 72 positives in 2019 and 84 in 2017.

Ingham didn’t have data as to how many total truckloads of milk were shipped in Wisconsin last year, but figures compiled by the National Milk Drug Residue Database showed that of 3,652,685 tests conducted nationwide between Oct. 1, 2019 and Sept. 30, 2020, a total of 337 tested positive, or 0.009%.

While positive tests have been trending downward, Wisconsin milk production has been increasing, Ingham notes, which makes the lower percentage of tainted truckloads even more meaningful.

As farms get larger, Ingham says, there is more at stake if a day’s milk output is tainted and has to be dumped.

“There’s certainly a motivation to stay on top of it,” he says. “As a farm gets bigger and has more employees, it makes sense that somebody would have a specific job to deal with that issue.”

La Crosse-based Kwik Trip is one of Wisconsin’s largest milk bottlers, with its own dairy plant bottling milk from 35 farms within a 100-mile radius of the bottling facility. John Laschenski, Kwik Trip’s director of dairy operations, says the company is taking in 15 loads of milk a day, seven days a week. That is equivalent to about 750,000 pounds – or 87,000 gallons – of milk per day.

The Kwik Trip milk plant staff members test each load for antibiotics and the company has a confirmatory lab to provide another layer of protection against antibiotics reaching the consumer.

“I would say in a year, out of all the trucks we receive, 15 trucks a day, 365 days a year, we probably average one truck per year that we get a positive (test result),” Laschenski says. “The producers do a really good job of keeping track of what is going on the truck. They know they are on the hook for that load if we find anything.”

rBST not in milk

Another concern of consumers in years past was the use of rBST, a synthetic growth hormone that was injected into cows to boost milk production. The federal Food and Drug Administration determined in 1993 that rBST, known by its trade name Posilac, does not change the composition of milk and is not harmful to humans. But that didn’t stop some consumers from being wary.

Twenty-eight years later, many milk bottlers still put a disclaimer on their labels that the milk does not come from cows treated with rBST. When they do so, they are required to add a line saying “no significant difference has been shown between milk derived from rBST treated and non-rBST treated cows.”

So, do consumers really care about the rBST issue, and is rBST still being used on many farms?

Brad Legreid, executive director of the Wisconsin Dairy Products Association, says he doesn’t know of any Wisconsin dairy plant that still accepts milk from cows treated with rBST, which means it is basically not being used on the farm level.

“I think there’s still a marketing angle these companies have to think about,” he says. “So much of the public thinks that non-rBST products are safer, so the bottlers think it’s not harmful to keep it on their product. Even though the industry is moving away from rBST, it’s not a quick turnaround to change the labels. (Changing a label) is usually not a real cost-effective thing to do.

“Bottlers are saying, ‘Does it really hurt to have it on there to be on the safe side?’ ”

‘Virtual non-issue’

John Umhoefer, executive director of the Wisconsin Cheese Makers Association, says rBST has become a “virtual non-issue” in the dairy industry, so he doesn’t know why milk bottlers are still using valuable label space to tell consumers it’s not being used by the farmers that supply their milk.

“Generally speaking, all the major bottlers went away from it,” Umhoefer says. “In my opinion there was not a problem with (rBST). It just became a consumer issue that went outside of science. But it’s certainly not the hot issue it once was.”

Kwik Trip’s Laschenski says he’s not sure if any milk bottlers are still using milk from cows treated with rBST, but as long as there is a possibility the product is being used, he likes to see the disclaimer on the Kwik Trip label to differentiate the company’s product.

“But the milk label is very valuable real estate – there’s not much room on there,” he says. “The next time we update our labels, whenever that happens, the question will come up, do we need this on our label anymore?”

Kim O’Brien, director of corporate communications for Dairy Farmers of America, the nation’s largest dairy cooperative, confirmed that “none of DFA’s farm family-owners are currently using rBST.”

Asked why DFA still uses the rBST disclaimer when very little if any of the product is used on farms, O’Brien says a majority of milk processed by DFA is sold to dairy product marketers and “it is their choice as to how they label those products.”

Posilac is sold to farmers by Elanco, Eli Lilly’s Animal Health Division. An Elanco spokesperson declined to provide specific information on current Posilac sales, saying the company has a “privacy policy in place that makes us unable to give you any information regarding our product.”

Ingham says there is no test to determine if milk comes from a cow treated with rBST, so the state relies on an affidavit program to hold dairy processors accountable for the claims they make on their labels.

Dairy plants used to have to get an updated affidavit from farmers every year to specify that they weren’t using rBST, but the rules were recently changed so dairy plants can keep farmer affidavits on file and only have to update them if something changes.

“The intel we had back when we changed the rule was that (rBST use on farms) is kind of a non-issue,” Ingham says. “But I can’t speculate on the feelings of the dairy plants as to what goes on the milk jugs.”

Massey lives near Barneveld, Wis.