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

The impact that ruminant production has on greenhouse gas emissions [nitrous oxide (N 2 O)] and the ability for
feeding to reduce greenhouse gas emissions continues to be an important issue for producers and industry
stakeholders. Hao et al. (2010) caution that although an increase in N nutrients passed into manure may be
beneficial for crop or forage production, N 2 O was produced and emitted at significantly higher levels in 60% of
cattle fed wheat DDGS, with a potential 37% increase in global warming.
Hao et al. (2009) found that when feeding 40% or 60% wheat DDGS, fecal total P and manure total P were
positively correlated to feed total P indicating that increased feed P intake also increased P excretion. Benke et
al. (2009) have shown that repeated applications of DDGS manure to soils continue to raise available P levels to
nearly two times that of conventional manure. The generally high water solubility of P negatively impacts water
quality and aquatic life. Hao et al. (2009) did determine that water-soluble P levels from 60% DDGS manure
can be maintained at control levels. The addition of Ca (limestone) to the diet fostered the formation of calcium
phosphate with low water-solubility.
Although this publication’s main focus is on feed characteristics and quality, animal care and manure
management implications must also be considered prior to implementing any feeding strategy. Therefore, it is
important to test manure to ensure spreading is in compliance with provincial manure regulations or agricultural
operations acts. Up to 75% more land may be required to apply 35% DDGS feedlot manure at proper nutrient
rates for crop uptake (Benson et al., 2005). Feeding above 20% wheat DDGS (at 40% and 60% wheat DDGS)
has shown significant negative differences in odour-causing volatile fatty acids, water-soluble P, and greenhouse
gas emissions versus controls (Hao et al., 2009, Hao et al., 2010). Mitigation may include moderation of wheat
DDGS levels (20% wheat DDGS inclusion is no different than manure produced from the current barley ration),
maintaining 2:1 Ca:P levels in the ration or spreading manure at lower rates over a larger land base.
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RUMINANT DIETS