title: Effect of bird-resistant and non-bird-resistant sorghum grain on amino acid digestion by beef heifers.
abstract: The effects of sorghum type on amino acid digestion were determined by feeding heifers (230 kg) equipped with ruminal, duodenal, and ileal cannulas bird-resistant (BR) or non-BR grains that had a normal or waxy endosperm (NORMAL-BR, WAXY-BR, NORMAL, WAXY). Dry-rolled grain diets were fed at 2% of BW in a 4 x 4 Latin square design. Total (TAA), essential (EAA), and nonessential (NAA) amino acid intake (grams/day) tended to be greater for BR than for non-BR grains. Feed (plus endogenous) amino acids reaching the duodenum were calculated by subtracting amino acids of microbial protein from total flow. Flow (grams/day) of total and feed TAA, EAA, NAA, and proline-rich-protein (sum of aspartate, glutamate, glycine, and proline) to the duodenum was greater (P < .05) for BR than for non-BR grains. The ratio between feed proline-rich-protein and NAA reaching the duodenum was similar to that noted with feed intake. Amino acid disappearance (grams/day) from the small intestine was unchanged (P > .10) by sorghum type, although the digestibility (percentage of duodenal flow) of TAA, EAA, NAA, and most individual amino acids was decreased (P < .05) for BR varieties. Amino acid flow to the cecum (grams/day) was generally greater for NORMAL-BR than for WAXY-BR (P < .10) or for NORMAL (P < .01) and greater (P < .10) for WAXY-BR than for WAXY.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Animal and Dairy Science, University of Georgia, Athens 30602-2771.
authors.forename: M N
authors.initials: MN
authors.lastname: Streeter
authors.forename: G M
authors.initials: GM
authors.lastname: Hill
authors.forename: D G
authors.initials: DG
authors.lastname: Wagner
authors.forename: F N
authors.initials: FN
authors.lastname: Owens
authors.forename: C A
authors.initials: CA
authors.lastname: Hibberd
mesh_terms: D000596:Amino Acids / Q000008:administration & dosage / Q000378:metabolism*; D000821:Animal Feed; D000818:Animals; D001717:Birds; D002417:Cattle / Q000502:physiology*; D004044:Dietary Proteins / Q000008:administration & dosage / Q000378:metabolism; D004063:Digestion; D004435:Eating; D002523:Edible Grain; D005260:Female; D005772:Gastrointestinal Transit; D007421:Intestine, Small / Q000502:physiology; D011485:Protein Binding; D013634:Tannins / Q000378:metabolism
chemical_list: D000596:Amino Acids; D004044:Dietary Proteins; D013634:Tannins