Wheat DDGS Feed Guide - Western Canadian Feed Innovation ...

Wheat DDGS In Aquaculture Diets
Limited information is available on feeding wheat DDGS to aquaculture species. Hilton and Slinger (1986)
demonstrated that it is feasible to use 10% corn DDGS in rainbow trout diets. However, as a salmonid species
which, like other carnivorous fish, require high levels of protein and fat and have little to no capacity to digest
fibre, corn DDGS is only marginally feasible as it contains high levels of fibre and only modest levels of protein
and fat. Wheat DDGS contains significantly higher levels of protein but less fat and more fibre than corn DDGS,
limiting its use in salmonid diets. Randall and Drew (2010) fractionated wheat DDGS, based on particle size,
and found that the fine components of the product are elevated in protein (43.2% vs 37.2% as fed basis) and
contained less neutral detergent fibre (21.6% vs 27.12% as fed basis), rendering the product more suitable
for salmonid diets. The digestibility of the energy and dry matter of the fine fractions of wheat DDGS (83% and
79%, respectively) were higher than in the starting material (75% and 66%, respectively) and were similar in
composition and digestibility to that of soybean meal.
Further improvements in the nutritive value of wheat DDGS were obtained through aqueous extraction of protein
from wet wheat distillers grains (WWDG). This method has the advantage of performing all fractionation steps
on WWDG before the drying process. Therefore, no additional drying costs are incurred in the production of
this product. This process increased the protein content of WWDG from 43.2-68.5% and decreased nonstarch
polysaccharides from 27.2-8.1%. The product also had significantly increased the apparent digestibility
coefficients for dry matter, gross energy and acid ether extract (P < 0.05) when fed to rainbow trout. The addition
of this product at up to 30% of the diet did not decrease the growth performance of rainbow trout. Wheat
DDGS may be added to salmonid diets at low levels but fractionation prior to feeding offers significant benefits
nutritionally and makes it more practical as an aquaculture feed.
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AQUACULTURE DIETS