Antibiotics and Milk in Quebec

This past weekend, I was discussing milk with a friend in Massachusetts. Although we are neighbours, how our milk is produced could not be more different. One of the main differences between conventional dairy farms in the USA and those in Quebec, is the use of antibiotics and growth hormone. Our average herd size is also considerably smaller, 52 in Quebec versus 700 south of the border, and more likely to be a family operation.

In Quebec, most cows consume food produced on the dairy farm itself. In addition to pasture, feed can include hays, grains and silage. Vitamins and minerals may be added to the feed. In the USA, conventional milk producers can also add antibiotics to the feed. However in Quebec, this practice is illegal. Similarly, in the USA, dairy farmers routinely use recombinant bovine growth hormone (BGH) to increase milk production, but in Canada the use of rBGH (known in Canada as recombinant bovine somatratropin; rBST) is not approved so this practice is not allowed.

That's not to say that Quebec dairy farms do not use antibiotics at all. Bovine mastitis, an infection of the teats, is a common problem in dairy farms, affecting about 80% of Quebec herds, and 39% to 92% of Canadian herds, based on data collected that looked at the most common cause, infection with s. aureus. When discovered, mastitis is routinely treated with systemic antibiotics. Cows may also be treated with antibiotics for other infections, and dry cows (cows not currently producing milk), I believe, may be given antibiotics prophylactic ally to prevent mastitis.

Organic farms are not immune from mastitis and other infections, and in Quebec farmers may use antibiotics twice during per year on any given cow, however most organic farmers will try to avoid antibiotic use altogether and use husbandry and milking methods that focus on prevention. Organic farmers may also try to treat mastitis without antibiotics.

I looked for an article comparing the incidence of mastitis or antibiotic use in traditional versus organic herds, but couldn't find one. My inclination is to believe that organic farms have a lower incidence of mastitis than conventional farms, and also use less antibiotics.

For me, the incidence of mastitis and the responsible use of antibiotics in animal husbandry is more of an issue than whether a farmer use antibiotics at all. And while I suspect that in Quebec, at least, conventional farms are probably trying as hard as organic farmers to keep their herds free from disease and lower use of antibiotics (I saw loads of articles raising awareness of antibiotic resistance and encouraging preventative practices), I will continue to buy organic milk whenever I can because I believe in the overall philosophy of organic farming, and want to support those farmers who have chosen this more difficult route. But it's also nice to know that conventional milk from Quebec farms may not be too different.

References: 1) Fédération ds producteurs du lait du Québec. The journey of milk from the farm to your table. Accessed April 27, 2009. 2) Olde Riekerink R and Barkema H. Mastitis: The Canadian Perspective. WCDS Advances in Dairy Technology (2006) Volume 18:275-283. 3) Canadian Bovine Mastitis Research Network (CBMRN) website. Accessed April 27, 2009. 4) Fédération d'Agriculture Biologique du Québec (FABQ) website. Accessed April 27, 2009. 5) Ecological Agriculture Projects. Treating Mastitis without Antibiotics. Accessed April 27, 2009.