Canola meal’s complexity suggested the use of a multiple enzyme package rather than a single enzyme treatment, said Bogdan Slominski, a professor of animal sciences at the University of Manitoba. The treatment has been found to release an additional 100 to 150 kcal/kg of apparent metabolizable energy (AME) from canola meal.
“The end goal of our research is to minimize the variability in the nutritive value of canola meal due to processing conditions and to increase the inclusion level of this valuable protein supplement in monogastric animal diets,” he told FeedNavigator.
Information on the research regarding enzyme use and other ways to decrease the amount of fiber in canola meal was presented at the International Rapeseed Congress in Saskatoon in July.
Multiple ways to deal with fiber
Canola meal can have total dietary fiber values that are higher than those of soybean meal, said Slominski. And, recent surveys of canola meal in Canada found the neutral detergent fiber to be about 29.6% of dry matter, and total dietary fiber to be 38%. The fiber can be hard to digest and may not affect nutrient use.
Using the enzyme suite on canola meal can unlock more nutritional potential from the fiber, he said.
“What we are achieving so far with the multi-enzyme is an extra 100 (Kcal/kg dry matter) of energy, so it is economical,” he said, adding that for the meal to better compete with soybean meal, it needed to provide more energy, which the enzyme technology is doing.
In addition to unlocking nutrients, the group researched ways to diminish the amount of fiber contained in the meal, said Slominski.
These have included work with low-fiber seeds like the yellow-seeded B. napus and canola-quality B. juncea mustard along with tail-end de-hulling, he said.
The transition from the black seed to the yellow will increase oil and protein available in the meal, he said. In a study done that compared feeding 15% black-seeded B. napus to the same amounts of the yellow-seeded B. napus or B. juncea to broiler chickens for 36 days, the birds were found to maintain similar weights. The study reported control birds fed wheat and soybean meal had a feed conversion ratio (FCR) of 1.53 kg feed/kg weight gain and a body weight gain (BWG) of 2.32 kg, those getting the black-seeded B. napus had 1.51 FCR and 2.3 kg BWG, results were 1.54 FCR and 2.19 kg BWG for yellow-seeded B. napus and B. juncea had 1.50 FCR and 2.31 kg BWG.
Similar results were reported for a study that fed diets comprised of 20% of the different canola meals to turkeys for 56 days.
The de-hulling process was found to concentrate the nutrients in the meal and increase the protein content from about 36.8% to 42%, he said. When fed to broiler chickens for 10 days the BWG for birds getting regular canola meal was 293.1 g and, for those getting the de-hulled canola meal, it was 279.7 g. Both groups of birds had the same FCR of 1.19 g feed/g gain.
A related study looking at the growth of pigs reported a higher overall average daily gain for the pigs getting the de-hulled canola meal than for those getting the regular canola meal – 417 g a day versus 377 g a day – and a slightly higher final body weight of 17.8 kg to 17.4 kg.
Meal variability
However, one concern about canola processing is the digestibility of amino acids can be damaged if it is over-heated during the pre-press solvent extraction, the researcher said. That damage limits the nutritional value present in the meal.
There also are some differences in the product that comes from different crushing plants, he added. There are 11 plants in Canada with two more currently in construction.
“The highest variability would be resulting from different processing conditions,” he said. “That’s why we’re doing surveys to determine the variability and finding the crushing plants that may be causing some issues.”
Use of canola
Currently canola is often used in in swine diets to provide amino acids, stated Canada’s Canola Council. It reports that recent studies have found benefits for grower-finisher pigs fed on diets of up to 25% canola meal.
The council said it is common to find canola meal in poultry feed, particularly for egg layers and in turkey feed. In broiler feed, usage can be up to 10% or more of the diet.
What’s next
The next steps for the researchers include continuing to survey the products from canola crushing plants and trying to establish methods to reduce the variability of product, said Slominski.
They also are looking at ways to increase the use of canola meal in animal feed diets, he said. Currently the level used is about 10% to 15%, but there may be ways to formulate a diet using 20% to 25%.
“Now it’s more about providing things to the feed industry and demonstrating things,” he said. “In general animal production these days is all about utilizing the products.”