Effects of nitrogen fertilization and dried distillers grains supplementation: forage use and performance of yearling steers.
In a 3-yr study, corn dried distillers grains plus solubles (DDGS) were evaluated as a substitute for forage and N fertilizer in yearling steers grazing smooth bromegrass. A total of 135 steers (330 +/- 10 kg) were used in a randomized complete block design to measure the effects of DDGS supplementation and N fertilization on animal and pasture performance. Steers were initially stocked at 6.8 animal unit month (AUM)/ha on nonfertilized smooth bromegrass pastures (CONT), at 9.9 AUM/ha on smooth bromegrass pastures fertilized with 90 kg of N/ha (FERT), or at 9.9 AUM/ha on nonfertilized smooth bromegrass pastures with 2.3 kg of DDGS DM supplemented daily (SUPP). Paddock was the experimental unit, with 3 replications per year for 3 yr. Paddocks were strip-grazed and put-and-take cattle were used to maintain similar grazing pressure among treatment paddocks during the 160-d grazing season. In vitro DM disappearance declined quadratically (P < 0.01), whereas CP and standing crop showed cubic responses (P < 0.01) throughout the grazing season. Crude protein was greater (P < 0.05) for FERT compared with CONT and SUPP. Standing crop was 18% greater (P < 0.01) for FERT than CONT and was 10% greater (P < 0.01) than SUPP. Adjusted stocking rates (AUM/ha) were greater (P < 0.01) for FERT and SUPP compared with CONT. Final BW were greater (P < 0.01) for SUPP steers compared with CONT and FERT steers. Similar results were observed for ADG, with SUPP steers gaining more (P < 0.01) compared with CONT and FERT steers. Total BW gain per hectare was increased (P < 0.01) by 53% with FERT and by 105% with SUPP. Feedlot ADG was similar among treatments (P = 0.88), and SUPP steers maintained their BW advantage through the finishing phase. Dried distillers grains can be used to substitute effectively for N fertilizer by increasing the performance of yearling steers grazing smooth bromegrass and increasing stocking rates compared with nonfertilized pastures.
Greenquist
M A
MA
Department of Animal Science, University of Nebraska, Lincoln 68583, USA.
Klopfenstein
T J
TJ
Schacht
W H
WH
Erickson
G E
GE
Vander Pol
K J
KJ
Luebbe
M K
MK
Brink
K R
KR
Schwarz
A K
AK
Baleseng
L B
LB
D000821:Animal Feed; D000822:Animal Husbandry; D000818:Animals; D031724:Bromus / Q000254:growth & development; D002417:Cattle / Q000254:growth & development / Q000502:physiology*; D019587:Dietary Supplements; D004435:Eating; D002523:Edible Grain; D005308:Fertilizers; D008297:Male; D009584:Nitrogen; D015430:Weight Gain / Q000502:physiology
D005308:Fertilizers; D009584:Nitrogen