Sixty-four crossbred (N30 months of age) non-lactating, non-pregnant
beef cows with body weight averaging 620±62 kg were
used. Cows were cared for according to Canadian Council on Animal
Care guidelines (CCAC, 1993) and fed at the Lethbridge Research
Centre. Cows were randomly assigned to one of four diets, with four
pens of four cows per diet. Cows had ad libitum access to feed and
water. Diets were designed to meet or exceed nutrient requirements
for mature cows (Nassu et al., 2011; NRC, 2000) and consisted of
50:50 forage to concentrate (dry matter basis) and were fed as total
mixed rations. Diets included hay control, barley silage control, hay
plus flaxseed and barley silage plus flaxseed. Flaxseed was ground
together with barley in a 7:3 ratio and flaxseed diets contained 15%
flax substituted for dry rolled barley (dry matter basis). Diets were fed
for 20 weeks. During the study two animals were withdrawn due
to lameness, one each from the silage and the silage plus flaxseed
treatments.