Cows fed canola meal make more milk, less gas

Canola meal improves the environmental footprint of milk production. A new study shows that cows fed canola meal will produce more milk while also reducing their methane emissions and nitrogen losses.

“Canola meal improves the environmental footprint of milk production.”
–Chaouki Benchaar

Chaouki Benchaar, research scientist with Agriculture and Agri-Food Canada in Sherbrooke, Quebec, led the research featured in “Diet supplementation with canola meal improves milk production, reduces enteric methane emissions, and shifts nitrogen excretion from urine to feces in dairy cows,” published in the September 2021 issue of Journal of Dairy Science. (journalofdairyscience.org)

Benchaar and his research colleagues found that methane emissions, as a percentage of gross energy intake, declined as the amount of canola meal in the diet increased. This energy was captured in greater milk production, rather than lost to the atmosphere.

The researchers also found that more of the dietary nitrogen from canola meal was converted to milk protein, and less was lost in the urine with each incremental increase in dietary canola meal. (See the table.) Urine nitrogen contributes to atmospheric ammonia and nitrous oxide.

“To the best of my knowledge, the 24 per cent inclusion of canola meal is the highest ever tested in a controlled study,”
—Chaouki Banchaar

“It is really interesting that canola meal reduces methane emissions, shifts nitrogen excretion from urine to feces (i.e. less potential nitrogen emissions) and improves performance at the same time,” says Benchaar. “Thus, canola meal improves the environmental footprint of milk production.”

The diets were balanced to provide 16 per cent crude protein, with all the supplemental protein in the control diet provided by soybean meal. The test diets contained (on dry matter basis), zero, 8, 16 or 24 per cent canola meal.  Dry matter intake and energy-corrected milk increased as canola meal in the diet increased, with no effect on feed efficiency (energy corrected milk/dry matter intake).

“To the best of my knowledge, the 24 per cent inclusion of canola meal is the highest ever tested in a controlled study,” says Benchaar. “The all-canola meal diet resulted in 2.2 kg more energy-corrected milk than the all-soybean meal diet.”

This research supports previous work on the life cycle analysis (LCA) model comparing cows in Quebec and Alberta that were fed canola meal versus soybean meal.  For more information on canola meal as a feed source for cows, poultry, hogs and more, please visit canolamazing.com. The site provides the latest research findings, including this study, as well as accurate feeding values for canola meal. The site also has the Canola Meal Feeding Guide.