Nutrient Behavior and Composition of Damaged Canola Seed

It is the protein and oil content of whole canola seed that gives it value. Analysis shows protein content is less affected by frost or weathering

in the whole seed but oil content varies more. The oil of oilseeds such as canola, like the starch of cereal grains, is the last major component to develop in the maturing process. Canola seed damaged by frost is prevented from maturing; hence the oil content of the seed is reduced. This is different from seeds that have matured or almost matured, and have a high content of green chlorophyll, with oil content closer to normal. Sample frozen canola on a dry matter basis has an average composition ranging from 21 to 24% crude protein and 31 to 42% oil depending on stage of maturity at time of frost damage. Recent feed analysis of a sample of more mature canola, having greater than 65% green seed had an analysis of 27.7% crude protein and 44.9% oil. Average analysis of #1 canola approximates 22 to 23% protein and 44 to 46% oil.

 

The presence of green chlorophyll in the oil is not considered a problem as practical experience in use and research with chickens has shown no negative effects. What is of concern is the processing of the seed to obtain full use and value. Significant improvements have been shown to occur with processing. 

 

 

Table 1.

 

  

Work supported by Saskatchewan Canola Development Commission

 

The canola seed being hard, small and round must be cracked to allow access by digestive enzymes. Grinding, pelleting and extruding are all processes to do this by. For on farm processing, grinding through a 1/8” or smaller hammermill screen along with 30 to 50% grain to avoid plugging should be done.

 

Use of Whole Canola Seed in Livestock and Poultry Diets

Cattle and Sheep: For ruminants the amount of whole canola seed used in diets for beef and dairy cattle and sheep is dependent upon the total fat or oil level in the diet. At higher concentrations usually above 5.5 to 6% of total diet dry matter fat interferes with fibre digestion and may reduce feed intake. However fat at lower levels if properly formulated into the diet becomes a safe and efficient manner in which to add energy. (One unit of fat contains 2.25 times the energy of one unit of starch). Most diets based on prairie feedstuffs usually do not contain more than 1.5 to 2.5% fat in total.

Whole canola seed can be used to advantage for growing and finishing animals and also for wintering beef cows. In feedlot diets levels up to 20% of total diet dry matter have been successfully fed providing total dietary fat dry matter % is below 6%. This could be 10% of whole canola if the oil content is 40% or 15% whole canola at 27% oil.

 

It can be fed mixed with grain at a level that will provide a maximum of 300 to 350 grams of oil per cow per day. In both growing and wintering beef cow diets, the added protein provided will also provide added value and may negate and/or reduce the need for protein supplementation.

 

High production dairy diets may use some added fat in the diet to provide additional energy in a form other than starch. Similar rules apply to dairy with whole canola seed as for beef cattle. Added dietary oil levels of up to 400 grams per cow per day can be used. Because of the unsaturated fat and interference with fibre digestibility much higher levels are not well tolerated without lowering butterfat levels or reducing feed intake. It is unusual though to require much more than 300 grams of added oil per cow per day in most diets.

 

Use similarly as for growing finishing beef cattle.

 

Damaged whole canola seed can provide valuable additions of protein (amino acids) and energy to swine diets. Total dietary fat levels should not exceed 5.5% for grower finishing pigs to avoid too soft a fat in the carcasses. In sow diets whole canola seed can be used to provide the added fat commonly added up to 12% of the sow feed. In swine diets processed canola seed also provides the added advantage of reducing dust in the diet. Experience with pork producers has indicated that whole canola seed is best fed to pigs greater than 25 kg of weight and that is it readily accepted at levels up to 12 -14% of the diet.

 

Added energy beyond barley with pigs and wheat with poultry is necessary to get added performance. With poultry this typically means oil or fat addition. For broilers levels of up to 10% of regular canola seed were found to be satisfactory in feeding trials at the University of Guelph (1977). Poultry have limited capability to handle fibre and better quality offgrade canola seed should be used. However, value in poultry diets is higher than other animals and can be a bargain. In general for poultry, whole canola should not exceed 10 to 12% of the total diet.

  

If you have not guessed it by now, a feed analysis is a must to not only feed whole seed canola, but also place a value on it. Both protein and energy in whole canola seed give it value. The more oil the more energy and at 20 to 22% protein it is much higher than most feeds. In a strict definition whole canola seed just qualifies as a protein supplement.

 

The value of whole canola seed for different species depends upon the demands of the diet. As an example, with poultry, high production dairy diets and sow diets, where oil or fat is added to increase energy level, whole canola seed has the greatest value. While in swine grower and finisher diets it can be used to supplement barley in place of wheat to provide greater energy, its value is intermediate. The following table shows the value of a whole canola seed containing 20.5% crude protein and 41% oil on an as fed basis. Feed prices per tonne for barley $102, wheat $125, corn $165, canola meal $180, soybean meal $335, barley silage $32, alfalfa hay $105 and tallow $510 were used. 

 

 

Table 2. August 2004 opportunity value of whole canola seed

(20.5% CP and 41% oil) in various feeding program

 

 

While these values are maximum opportunity values, a simple deduction for processing and transport can be used to determine a more realistic value