2014. Effects of replacing barley grain with graded levels of wheat bran on rumen fermentation, voluntary intake and nutrient digestion in beef cattle. Can. J. Anim. Sci. 94: 129Á137. Abrasion-milled wheat bran (AMWB) is a relatively new by-product from wheat-based ethanol production. Few published studies are available on the nutritional value of this by-product feed for growing cattle. The objective of this trial was to evaluate the effects of replacing rolled barley with AMWB on apparent nutrient digestibility, voluntary intake and rumen fermentation parameters of beef heifers fed a backgrounding diet formulated to 1.50 and 0.91 Mcal kg (1 dry matter (DM) of NE m and NE g , respectively. Five spayed and rumen-cannulated Angus heifers (584940 kg) were used in a 5 )5 Latin square design. The control diet consisted of 36% barley silage, 24% grass hay, 8% supplement and 32% rolled barley grain (DM basis). Dietary treatments replaced barley grain with AMWB at 8, 16, 24 and 32% of the diet DM. Voluntary DM (P00.30) and organic matter (OM) (P00.19) intake were not affected by AMWB inclusion level. Mean rumen pH (P 00.68) as well as duration (min) (P00.68) and area under the pH curve 5.8 (P00.27) were not affected by AMWB. Other than acetate, which linearly increased (P00.03) with increasing AMWB, effects on rumen volatile fatty acids or NH3-N levels were minimal. There was a linear decrease (P B0.01) in DM, OM and gross energy digestibility with increasing AMWB, while acid (P00.01) and neutral (P00.03) detergent fibre digestibility decreased in a quadratic manner. A similar quadratic trend (P 00.06) for decreased digestible energy content was also noted with increasing levels of AMWB. Crude protein digestibility was not affected (P00.94) by treatment. These results indicate AMWB will not support similar gains to barley grain in growing diets due to reduced total tract nutrient utilization and lower digestible energy content.

Amat, S., McKinnon, J. J., Penner, G. B., Simko, E. and Hendrick, S. 2014. Evaluation of mineral status in high dietary sulfur exposed or sulfur-induced polioencephalomalacia affected beef cattle. Can. J. Anim. Sci. 94: 139–149. We examined the mineral status in beef heifers fed high S containing diets with differing forage-to-concentrate ratio (F:C), and in S-induced polioencephalomalacia (PEM) affected feedlot steers. A metabolism trial was conducted as a randomized complete block design using a 2×2 factorial treatment arrangement with main effects of dietary S and F:C using 16 ruminally cannulated heifers. The F:C was modified by altering the proportion of barley silage (4 vs. 51% dry matter), whereas, the S content was modified by using differing sources of wheat dried distillers’ grains with solubles (WDDGS) to achieve low and high S diets (LS=0.30 vs. HS=0.67%). Minerals including Cu, Co, Fe, Mg, Mn, Mo, Se and Zn were determined from rumen fluid, blood, brain tissue and urine. Urinary mineral excretion was also assed. During the course of the metabolic trial, an outbreak of S-induced PEM in a commercial feedlot was documented and brain minerals of these PEM steers (n=4) were contrasted with the experimental heifers fed HS diet. There were no interactions between dietary S concentration and F:C (P>0.05). Heifers fed HS diet had reduced (P<0.05) mineral intakes (except for Mo), ruminal Co, Fe and Mn, and serum Mg and Fe relative to those fed LS diet. Heifers fed low F:C diet had reduced (P<0.05) Cu, Fe, Mo and Se intakes, greater (P<0.05) ruminal Cu, Fe, Mn and Zn, and reduced (P<0.05) serum Cu and Se, and greater (P<0.05) serum Mg than heifers fed high F:C diet. Brain minerals were not affected (P>0.05) by F:C or dietary S. However, the PEM brains had reduced Cu (P=0.058), Fe (P=0.003) and Mo (P<0.001) relative to normal brains. Dietary S and F:C did alter the mineral status of the heifers, but no deficiencies or PEM were induced.