Winnipeg, Manitoba (October 17, 2023) — When U.S. producers and nutritionists look at protein options for dairy cows, canola meal can be a game changer. It’s a well-researched feed ingredient that consistently provides value, including improved milk production and lower greenhouse gas emissions.1-6 But canola’s value in dairy rations has historically been underestimated.
“When compared to soybean meal, we’ve consistently seen 2 pounds more milk in mid-lactation cows and even better in early-lactation cows,” said Essi Evans, Ph.D., E&E Technical Advisory Services.1-6 “From a sustainability perspective, we’re also learning that feeding canola meal leads to reduced methane gas output.”1-6
Canola meal boasts a well-balanced amino acid profile
One of the contributing factors behind canola meal’s higher milk production is its amino acid profile. Amino acids are the building blocks of protein — they are nitrogen-containing molecules that are required by the body, but dairy cows cannot produce enough on their own, and it can be hard for cows to get enough in their diets, particularly in early lactation or for high-producing cows.
“Canola meal’s amino acid profile most closely matches milk, when compared to any other vegetable protein source, meaning it provides amino acid balance,” explained Brittany Wood, Director, Canola Utilization, Canola Council of Canada.
Wood added that canola meal has high methionine content, which is an important limiting amino acid for dairy cows.
Table 1. Amino acid contribution comparisons
Compared to soybean meal, canola meal contains more methionine and histidine and comparable levels of lysine (Table 1), three key amino acids for producing milk protein. As a result, diets containing canola meal can be formulated with less protein, while meeting the amino acid needs for milk production.
Wood added, “More of that ideal amino acid profile gets taken right to the intestine to go to the mammary gland. Cows also increase their dry matter intake, so they eat more. They produce really good-quality milk as a result. Cows are not only producing more milk when they’re fed canola meal, they’re keeping that persistency throughout a longer period [Figure 2].”7
Figure 2. Differences in milk yield over the duration of the feeding trial7
SBM = soybean meal; CM = canola meal
Canola meal contains higher levels of RUP compared to soybean meal
Another factor behind canola meal’s higher milk production is its rumen-undegraded protein (RUP) value.
As protein passes through a cow’s digestive system, it is either classified as rumen-degraded protein (RDP) or rumen-undegraded protein (RUP).
- RDP is used by microbes, or bugs within the cow’s rumen, and is not available to be absorbed by the cow.
- If the protein leans heavier toward RUP, it’s more efficient for the cow to break down, and more valuable to its body. That’s because RUP bypasses the rumen, is disassembled into amino acids within the small intestine, and is then absorbed into the bloodstream. These absorbed amino acids help maximize milk production.
“Some proteins in canola meal are more difficult to digest by rumen microbes than others, so when feed moves through the rumen to the lower intestines, the RUP is the part the bugs were unable to degrade,” Dr. Evans explained. “Canola meal has a fairly high RUP value. As a result, these very excellent proteins can escape the rumen and be available.”
Canola meal can play an active role in reducing greenhouse gas and ammonia emissions
Feeding canola meal not only helps cows efficiently break down protein, maintain balanced amino acids and achieve higher milk yields, it also can contribute to reduced greenhouse gas emissions. Studies have demonstrated that replacing soybean meal with canola meal results in cows producing less methane gas, and also reduces milk urea nitrogen, urine urea and ammonia output (Table 2).1-6
“We have some really interesting new information on how cows are utilizing protein in the rumen, and producing less methane as a result when they’re eating canola meal,” asserted Wood. “Also, improving protein efficiency by not overfeeding protein, and providing proteins with a good amino acid balance, can reduce nitrous oxide production while often saving costs.”
Wood noted that projections for canola production are favorable for the foreseeable future. “The primary value for canola is in the oil. Right now, there is a very high demand for canola oil, and that’s only going up,” she said. “In the next two to three years, we’re going to see canola processing capacity increase significantly in North America, and that’s going to mean even more canola meal will be available for dairy producers in the United States.”
Table 2. Relationship between the level of inclusion of canola meal in the diet and methane output as determined in one study.1
About Canolamazing
Canola meal is a coproduct of canola processing and is approximately 36 percent crude protein, with a high bypass protein value and amino acid profile well suited for milk production. Because of its high protein content, canola meal is often used as a protein supplement for animal feeds, including dairy rations. Visit www.canolamazing.com to learn more.
References:
1 Benchaar C, Hassanat F, Beauchemin KA, et al. Diet supplementation with canola meal improves milk production, reduces enteric methane emissions, and shifts nitrogen excretion from urine to feces in dairy cows. J Dairy Sci 2021;104(9): 9645–9663.
2 Gidlund H, Hetta M, Krizsan SJ, et al. Effects of soybean meal or canola meal on milk production and methane emissions in lactating dairy cows fed grass silage–based diets. J Dairy Sci 2015;98(11):8093–8106.
3 Holtshausen L, Benchaar C, Kröbel R and Beauchemin KA, Canola meal versus soybean meal as protein supplements in the diets of lactating dairy cows affects the greenhouse gas intensity of milk. Animals 2021;11(6):1636.
4 Lage CFA, Räisänen SE, Stefenoni H, et al. Lactational performance, enteric gas emissions and plasma amino acid profile of dairy cows fed diets with soybean or canola meals included on an equal protein basis. J Dairy Sci 2021;104(3);3052–3066.
5 Moore SAE, Kalscheur KF, Aguerre MJ and Powell MJ. Effects of canola meal and soybean meal as protein sources on methane and ammonia emissions of high-producing dairy cows. J Animal Sci 2016;94(Suppl 5):572.
6 Reynolds MA, Brown-Brandl TM, Judy JV, et al. Use of indirect calorimetry to evaluate utilization of energy in lactating Jersey dairy cattle consuming common coproducts. J Dairy Sci 2019;102(1):320–333.
7 Kuehnl J and Kalscheur K. 2022. Production effects of feeding soybean meal versus canola meal to dairy cows with low and high residual feed intake. J Dairy Science 105(Suppl 1):71.
