title: Influence of feeding increasing levels of dry corn distillers grains plus solubles in whole corn grain-based finishing diets on total tract digestion, nutrient balance, and excretion in beef steers.
abstract: Four crossbred steers (average BW = 478 ± 33 kg) were used in a 4 × 4 Latin square design to determine the effects of dietary concentration of dry corn distillers grains plus solubles (DDGS) in whole corn-based finishing diets on total tract digestion and nutrient balance and excretion. The DDGS were fed at 0% (control), 16.7%, 33.3%, and 50% of dietary DM. All diets contained 10% (DM basis) alfalfa/grass haylage and were formulated to meet or exceed the estimated requirements for CP. Steers were fed the experimental diets ad libitum for a 14-d adaptation period followed by a 5-d period for fecal and urine collection. Increasing concentration of DDGS in diets from 0 to 50% of DM linearly decreased (P < 0.05) total tract DM and starch digestibility (from 77.8 to 72.9%, and 89.2 to 81.5%, respectively). Daily N and P intakes linearly increased (P = 0.06 and P = 0.01, respectively) with increasing DDGS concentration. Fecal and urinary N, P, S, Mg, and K excretion linearly increased (P < 0.05) with increasing DDGS concentration; however, Se and Na excretion did not differ (P > 0.38) among treatments. Retention (g/d; intake minus urinary and fecal excretion) of N did not differ (P > 0.16) among treatments. Retention of P tended (P = 0.07) to linearly increase and retention of S (g/d) linearly increased (P = 0.004), with increasing DDGS concentration. There were no effects (P > 0.16) of dietary treatment on digestion and retention of Se, Mg, K, and Na. Plasma P and S concentrations increased (P = 0.03 and 0.01, respectively) with increasing DDGS concentration. These data indicate that feeding DDGS up to 50% of dietary DM in whole corn grain-based finishing diets does not have a negative effect on nutrient retention but decreases digestibility. Total excretion of N, P, Ca, Mg, S, and K increased as DDGS concentration increased.
authors.affiliation: Department of Animal and Poultry Science, University of Guelph, Guelph, ON, Canada N1G 2W0.
authors.forename: H
authors.initials: H
authors.lastname: Salim
authors.forename: K M
authors.initials: KM
authors.lastname: Wood
authors.forename: M K
authors.initials: MK
authors.lastname: Abo-Ismail
authors.forename: P L
authors.initials: PL
authors.lastname: McEwen
authors.forename: I B
authors.initials: IB
authors.lastname: Mandell
authors.forename: S P
authors.initials: SP
authors.lastname: Miller
authors.forename: J P
authors.initials: JP
authors.lastname: Cant
authors.forename: K C
authors.initials: KC
authors.lastname: Swanson
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D002417:Cattle / Q000502:physiology* / Q000652:urine; D004032:Diet / Q000662:veterinary*; D004063:Digestion / Q000502:physiology*; D005243:Feces / Q000737:chemistry; D008274:Magnesium / Q000378:metabolism; D008297:Male; D000455:Medicago sativa; D010758:Phosphorus / Q000097:blood / Q000378:metabolism; D006109:Poaceae; D011188:Potassium / Q000378:metabolism; D012643:Selenium / Q000378:metabolism; D013455:Sulfur / Q000097:blood / Q000378:metabolism; D003313:Zea mays / Q000737:chemistry*
chemical_list: D010758:Phosphorus; D013455:Sulfur; D012643:Selenium; D008274:Magnesium; D011188:Potassium