In Depth

Antibiotics and milk: What's the difference between regular and organic?

If you think organic milk comes from cows that can't be treated with antibiotics, think again. Industry experts explain the real difference between regular and organic milk.

We've got the answer — and it may surprise you

Consumers are buying more and more organic milk, but how much do they really know about how it is produced? We take a closer look. (Christinne Muschi/Reuters)

News this week that 11 B.C. dairy farms were fined for antibiotics detected in their milk might have shoppers wondering if they should be reaching for organic products next time they hit the dairy aisle.

Many people might not realize organic dairy operations can still treat cows with antibiotics.

But neither organic nor regular dairy products are allowed to have any trace of antibiotics. 

So we decided to take a closer look to find out what consumers are really getting when they pay a premium for organic dairy products.

We spoke to three experts from inside the dairy industry to learn how the system works.

Does regular milk have antibiotics in it?

B.C. has some of the highest standards for milk production in the world, with zero tolerance for antibiotics in milk, according to Crites.

But if an animal is ill and needs antibiotics, then it's treated with antibiotics, says Hargreaves.

"That is basic animal welfare," he says.

The animal is removed from production during treatment, and kept out for three or four additional days, depending on the product used, in order to ensure the antibiotics have cleared its system.

"There may be a little bit of variability between cows, but we can be assured that when that withdrawal time is complete, that residue is out of their system completely," says Wiens.

Who is testing to ensure this?

Hargreaves says the industry uses several levels of testing to keep antibiotics out of all milk and dairy products sold in Canada.

Once the withdrawal period ends, the farmer can test the animal's milk before putting the cow back in production.

A sample is then taken of the farm's milk by the tanker truck driver before loading it up for delivery to the processor.

The processor then tests the tanker load before it enters the facility. If antibiotics are detected, the previous samples are tested to identify the source.

Any farm that supplied contaminated milk is fined and liable for the entire cost of dumping and testing the tanker load of milk, which can be thousands of dollars.

In addition, the whole farm is cut from the supply chain until the problem is solved, costing the farm even more in lost production.

"It is absolute devastation and a huge failure on the part of the farmer," says Wiens. "It is taken very personally by the farmers … so certainly the focus on farms is to make sure these things don't happen."

Finally, the B.C. Ministry of Agriculture performs random tests during inspections for antibiotics in milk and applies the same penalties for violations, notes Hargreaves.

Organic or regular dairy farm? It's hard to tell the difference unless you know what the cows are fed. (Ryan Remiorz/Canadian Press)

Are antibiotics used when animals are not sick?

Farmers are not allowed to use antibiotics in regular feedings to try to boost health or production, Wiens says.

"No, that it is not available. We don't do general treatments for the entire herd," says Wiens. "When we use antibiotics, they are specifically used on animals that are sick."

A sick animal doesn't have to be examined by a vet before antibiotics are administered. Instead, the farmer makes the diagnosis, determines the treatment and makes a permanent record of the treatment.

The record-keeping is a regulated part of Canada's food safety system, and is checked by the vet during regular visits to inspect the whole herd.

Are hormones used to produce Canadian milk?

Health Canada doesn't permit the use of hormones to increase growth or production of milk, according to Wiens

"We don't use production hormones that they have in some countries," he says, referring to the use of bovine growth hormone to boost milk production in the U.S.

But there are certain approved hormones for synchronizing the heat cycles of cows, he notes. 

"That would be a very specific thing. That is on an individual basis under the direction of a vet," he said.

And during treatment, he says, that cow would be approved for regular but not organic milk production.

So what is organic milk then?

An organic milk cow that falls sick can be treated with antibiotics, too, Wiens says, but is typically kept out of production longer after treatment.

According to Canadian guidelines, that withdrawal period is twice the regular period or at least two weeks, whichever is longer.

And if the animal is treated with antibiotics more than once in a year, it is permanently removed from the production of organic milk, said Wiens.

"It is not based on the science of it, but is more of a philosophical perspective," he said.

The main difference is that organic milk comes from cows that are fed with organically grown feed, says Wiens,

That means feed grown without the use of synthetic pesticides, herbicides, fungicides or fertilizers, and produced without nitrogen-based fertilizers or genetically modified organisms.

But in addition to the organic feed rules, there are unique animal welfare requirements for organic dairy cows, including access to more outside grazing and restrictions on using electric trainers on the animals.

Are there nutritional differences?

Many supporters of organic farming say outdoor grazing in particular leads to more nutritious products.

And according to Health Canada what the cow is eating is more influential than whether the particular feed is produced organically or conventionally.

"The nutritional content of milk depends on a number of factors, including genetics, season, climate, and feeding practices," said a statement from Health Canada. 

"For example, there is evidence that milk fatty acid composition varies with feeding regime, and that cows that eat fresh forage produce milk with more favourable fatty acids compositions compared to cows not fed fresh forage."

"There are some emerging studies suggesting that organic milk may contain higher levels of certain nutrients compared to conventionally produced milk, but it is unclear if these differences can be important enough to consider having an impact on human health," said a statement from the Canadian Dairy Board of Canada.

"Overall, the differences between organic and conventional milk composition would have very little impact on the overall intake of nutrients in a diet that includes all food groups," the statement notes.

What about pesticide and drug residues?

According to the most recent Health Canada report on chemical residues in food, no pesticides were detected in Canadian dairy products during the 2013 to 2014 period.

A residue from DDT was detected in six samples of imported cheese, but at levels below the maximum residue limits.

"Although DDT is no longer registered as a pesticide in Canada and many other countries, residues may persist in the environment and bioaccumulate in animal products," said the 2014 report.

The same report also found after testing 537 samples of Canadian dairy products, 31 had detectable level of veterinary drugs, but only five had levels above the maximum residue level permitted.

Imported dairy products didn't test quite as well.

Of 333 imported dairy products tested, 172 had detectable residues for veterinary drugs and 66 had unacceptable levels of drug residues.

The report did not make any distinction between organic and non-organic products, leaving it up to consumers to decide if the premium product is worth the extra cost.

How much have farms been fined?

As in every province, B.C.'s dairy industry is governed by a mixture of provincial and federal regulations and boards.

Eleven B.C. dairy farms were fined a total of $65,000 after antibiotics were detected in their milk between August 2015 and July 2016.

According to Crites, the total fines for previous years were:

  • 2015: $67,393
  • 2014: $83,547
  • 2013: $132,580

The B.C. Milk Marketing Board does not reveal the names of the farms fined.

Follow CBC journalist Mike Laanela on Twitter at @mlaanela