title: Effects of feeding aspirin and supplemental vitamin E on plasma concentrations of 3-methylindole, 3-methyleneindolenine-adduct concentrations in blood and pulmonary tissues, lung lesions, and growth performance in feedlot cattle.
abstract: OBJECTIVE
  To evaluate the effect of feeding aspirin and supplemental vitamin E on growth performance, lung lesions, plasma concentrations of 3-methylindole (3MI), and 3-methyleneindolenine (3MEIN)-adduct concentrations in blood and pulmonary tissues of feedlot cattle.
  
  
  METHODS
  256 crossbred steers; 64 cattle were used in experiment 1 and 192 cattle were used in experiment 2.
  
  
  METHODS
  A 2 X 2 factorial design was used for each experiment. Treatment factors were aspirin (0 or 3 g daily) and vitamin E (200 or 1,500 IU daily). Steers were housed in pens (8 steers/pen). Steers were slaughtered on days 59 and 138 for experiments 1 and 2, respectively. Lungs were grossly evaluated. 3MEIN-adduct concentrations were determined, and blood and pulmonary tissues.
  
  
  RESULTS
  Treatment was not associated with improvement or adverse effects on weight gain, dry-matter intake, or feed efficiency in experiment 2. In experiment 1, 36 of 63 (57.1%) steers had lung lesions. Lesions were not associated with treatment or concentrations of 3MI and 3MEIN-adduct. Plasma 3MI concentration and concentrations of 3MEIN-adduct in blood and pulmonary tissues were 3.11 microg/mL, 0.51 U/microg of protein, and 0.49 U/microg of protein, respectively. Aspirin was associated with increased blood concentrations of 3MEIN-adduct for diets that did not contain supplemental vitamin E.
  
  
  CONCLUSIONS
  Differences n performance of feedlot steers were not associated with treatment diet. It is possible that concurrent exposure of feedlot cattle to other factors typically associated with development of respiratory tract disease would affect these findings.
authors.affiliation: Integrated Livestock Management program, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA.
authors.forename: Guy H
authors.initials: GH
authors.lastname: Loneragan
authors.forename: Paul S
authors.initials: PS
authors.lastname: Morley
authors.forename: John J
authors.initials: JJ
authors.lastname: Wagner
authors.forename: Gary L
authors.initials: GL
authors.lastname: Mason
authors.forename: Garold S
authors.initials: GS
authors.lastname: Yost
authors.forename: Mike A
authors.initials: MA
authors.lastname: Thoren
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Wittum
authors.forename: Tammy M
authors.initials: TM
authors.lastname: Bray
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage; D001241:Aspirin / Q000008:administration & dosage*; D001835:Body Weight / Q000502:physiology; D002417:Cattle / Q000254:growth & development*; D002418:Cattle Diseases / Q000378:metabolism* / Q000473:pathology; D019587:Dietary Supplements; D007211:Indoles / Q000097:blood / Q000378:metabolism*; D008168:Lung / Q000378:metabolism / Q000473:pathology; D008297:Male; D011897:Random Allocation; D012140:Respiratory Tract Diseases / Q000378:metabolism / Q000473:pathology / Q000662:veterinary*; D012862:Skatole / Q000097:blood / Q000378:metabolism*; D014810:Vitamin E / Q000008:administration & dosage*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D007211:Indoles; D014810:Vitamin E; C097745:3-methyleneindolenine; D012862:Skatole; D001241:Aspirin