title: Influence of roughage and grain processing in high-concentrate diets on the performance of long-fed Holstein steers.
abstract: The effects of roughage source and timing of inclusion in high-concentrate diets on feedlot performance were evaluated in each of 2 yr with 144 and 120 long-fed Holstein steers, respectively. Roughage, when included in the diet, was delivered in a built-in-roughage (BIR) pellet supplying 15 and 6% roughage (percentage of DM) or hay crop silage (HCS) supplying 7 and 10% roughage (percentage of DM) for the growing and finishing periods, respectively. The six dietary treatments (two pens each) investigated were continuous whole corn and pelleted supplement (no added roughage; WSC-PEL); BIR with cracked corn either in the growing (BIR-G) or finishing (BIR-F) period with whole corn being fed with pelleted supplement when BIR was not part of the diet; BIR and cracked corn fed continuously (BIR-CONT); and two HCS treatments in which the corn was fed either whole (HCS-WSC) or cracked (HCS-CSC) for the entire feeding period. Replicates were slaughtered 4 and 3 wk apart for yr 1 and 2, respectively. Pooled daily gains (yr 1 and 2) for the entire trial (1.39 to 1.45 kg/d) were not different (P > .05). Daily DM and concentrate intakes were lower (P < .001) and gain efficiency was higher (P < .001) for the WSC-PEL than for the other treatments. Carcass characteristics were similar among treatments except for an improved yield grade (P < .02) for the HCS treatments over the BIR treatments. The WSC-PEL treatment was the most profitable (+/steer) and the BIR-CONT diet was the least profitable. The HCS treatments were the most profitable of the roughage treatments. A newly proposed intake prediction equation for feedlot cattle performed similarly to the 1984 NRC equation with long-fed Holstein steer calves.
authors.affiliation: Department of Animal Science, Cornell University, Ithaca, NY 14853, USA.
authors.forename: M J
authors.initials: MJ
authors.lastname: Traxler
authors.forename: D G
authors.initials: DG
authors.lastname: Fox
authors.forename: T C
authors.initials: TC
authors.lastname: Perry
authors.forename: R L
authors.initials: RL
authors.lastname: Dickerson
authors.forename: D L
authors.initials: DL
authors.lastname: Williams
mesh_terms: D000821:Animal Feed / Q000592:standards*; D000818:Animals; D001823:Body Composition / Q000502:physiology; D002417:Cattle / Q000254:growth & development* / Q000502:physiology; D004043:Dietary Fiber / Q000592:standards*; D002523:Edible Grain / Q000592:standards*; D008297:Male; D008460:Meat / Q000592:standards; D018803:Models, Economic; D011897:Random Allocation; D013997:Time Factors; D003313:Zea mays / Q000592:standards