Flax at 80 g/kg of dietary dry matter in growing (0.4 concentrate) and finishing (0.8 concentrate) diets replaced linseed meal and a portion of the corn.
Data were analyzed for the main effects of ration type (growing or finishing) and flax inclusion (with or without flax).
Diets were formulated to contain 140 g/kg crude protein for growing and finishing. No differences were observed for dry matter intake (10.2 ± 0.54 kg/d; 2.4 ± 0.09% of body weight).
Flax inclusion decreased microbial organic matter flow at the duodenum. Total tract organic matter digestion was greater for steers fed finishing diets and apparent ruminal organic matter digestibility tended to be greater for steers fed finishing diets.
Steers consuming finishing diets had greater total tract crude protein digestion. Microbial efficiency was not affected (P=0.36; g N/kg OM) by diet type or flax inclusion.
Steers fed growing diets had greater ruminal aNDF and ADF digestion. Steers consuming flax had lower ruminal ammonia. There was no effect of flax on CP, aNDF, ADF, and organic matter ruminal and total tract digestion.
Results indicate that substituting 8% flax for part of corn and linseed meal in growing and finishing diets by beef cattle did not alter organic matter and crude protein digestion.