title: Effect of reconstituting field-dried and early-harvested sorghum grain on the ensiling characteristics of the grain and on growth performance and carcass merit of feedlot heifers.
abstract: The objective of this study was to determine whether reconstituting field-dried and early-harvested sorghum grain affected the fermentation characteristics and feed value of the ensiled grain when fed to feedlot heifers. In Trial 1, sorghum grain was harvested at 14% moisture, rolled, and reconstituted to 25, 30, or 35% moisture, then ensiled in laboratory-scale silos. Lactic acid concentration increased (d 5 to 90) and pH decreased more rapidly (d 3 to 90) as moisture level increased (P < .05). Acetic acid concentration increased (P < .05) with moisture and day postfilling. Concentration of ethanol was highest (P < .05) in the 30 and 35% moisture grains from d 1 to 5, but by d 90 the ethanol concentration in the 25% moisture grain exceeded (P < .05) that of the two higher-moisture grains. Ammonia N concentration was lowest (P < .05) in the 25% moisture grain at all sampling times postfilling. In Trial 2, 288 heifers (BW = 286+/-83 kg) were used to compare the feeding value of rolled, ensiled sorghum grain harvested at 25% moisture to the same grain reconstituted to 30 or 35% moisture. A steam-flaked corn (SFC) diet served as the control. Final live weight; ADG; hot carcass weight; backfat depth; marbling score; kidney, pelvic, and heart fat; and liver abscess score were not affected by grain treatment (P > .10). Dry matter intake was highest (P < .10) for heifers fed the 25 or 30% moisture sorghum grain diets and lowest for those fed the SFC diet; DMI for heifers fed the 35% moisture sorghum grain diet was intermediate. Feeding 35% moisture sorghum grain improved gain efficiency (P < .10) compared with feeding 25 or 30% moisture sorghum grain by 9.0 and 5.7%, respectively. We conclude that reconstituting sorghum grain beyond the typical moisture levels of 25 to 30% would enhance the fermentation characteristics of the ensiled grain and improve gain efficiency in feedlot heifers.
authors.affiliation: Southwest Research-Extension Center and Department of Animal Sciences and Industry, Kansas State University, Manhattan 66506-0201, USA.
authors.forename: G L
authors.initials: GL
authors.lastname: Huck
authors.forename: K K
authors.initials: KK
authors.lastname: Kreikemeier
authors.forename: K K
authors.initials: KK
authors.lastname: Bolsen
mesh_terms: D000822:Animal Husbandry / Q000379:methods*; D000818:Animals; D001823:Body Composition; D002417:Cattle / Q000254:growth & development*; D002523:Edible Grain / Q000592:standards*; D005260:Female; D006863:Hydrogen-Ion Concentration; D012820:Silage