Source: Canola Council of Canada
A new literature review in the international journal, Advances in Dairy Research, examined 20 years’ worth of canola meal studies in dairy rations.1 “The research showed that canola meal is a high-quality protein feed ingredient that boosts milk production,” said author Brittany Wood, Director, Canola Utilization, Canola Council of Canada. “We’re also learning that it helps reduce methane emissions in dairy herds.”
“I was impressed by the large number of feeding trials that had been conducted in the past two decades,” stated Essi Evans, Ph.D., E&E Technical Advisory Services. “It’s rare to be able to find so many studies on a commodity ingredient. The information can be a valuable resource for dairy nutritionists, and help them accurately formulate diets that take full advantage of the ingredient.”
The review summarizes information on canola meal’s palatability, protein and amino acid value, fatty acid composition and micronutrient profile:
· Palatability. Dry-matter intake frequently improves when canola meal either partially or fully replaces other vegetable proteins, such as soybean meal or distillers’ grains. “We’ve been able to feed diets with up to 24% canola meal with no drop in dry-matter intake,” Evans said.
Table 1. Recent results show the effects of canola meal feeding levels on dry-matter intake and energy-corrected milk. All diets contained 16% crude protein.2
Protein and amino acid value. When compared to soybean meal, more of the protein in canola meal escapes rumen degradation — meaning it becomes more efficient for the cow to use for maintenance and milk production. “Canola meal has an amino acid profile that most closely matches milk, when compared to any other vegetable protein source, which provides amino acid balance,” explained Wood. “Canola meal also has high methionine content, an important limiting amino acid for dairy cows.”
Table 2. Milk protein score comparison of amino acid profile of proteins with requirements for milk synthesis. (A score of 1.00 = perfect.)
· Fatty acid composition. Canola meal has a higher fat content than many other vegetable proteins. The fatty acid composition is highest in oleic acid. This fatty acid is highly digestible and is less likely to cause milk fat depression than fats that contain high amounts of linoleic acid.
· Micronutrient profiles. Canola meal, like many vegetable proteins, is a rich source of phosphorus. Unlike other protein sources, canola meal has a dietary cation-anion balance ideal for use in diets for close-up dry cows.
When compared to soybean meal, results from 22 studies demonstrated a 2.4-pound advantage in milk yield for canola meal. Fewer mid-lactation feeding trials have been conducted comparing canola meal with other vegetable proteins. Results are provided for trials in which canola meal was compared to cottonseed meal, distillers’ grains, sunflower meal, brewery grains, flax meal and rapeseed meal. Recent studies have demonstrated significant advantages with respect to both milk yield and feed efficiency.
“Even with greater milk production, blood and milk urea nitrogen tends to be lower when canola meal is the primary supplemental protein,” explained Evans. “This means that the protein is used efficiently for the production of milk protein. There have been three meta-analyses confirming this effect.”
Canola meal can play a role in reducing greenhouse gas emissions
Findings regarding canola meal’s ability to reduce greenhouse gas output are also included in the review. The reduction in methane output is proportional to the canola meal inclusion rate in the diet.
“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,” Wood concluded. “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.”
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.