title: Effects of dietary energy and starch concentrations for newly received feedlot calves: II. Acute-phase protein response.
abstract: Two hundred forty five market-stressed bull and steer calves (205 +/- 14 kg) were received in January and September 2001 to determine the response of acute-phase proteins to dietary energy and starch concentrations and to determine whether acute-phase proteins could be used as a diagnostic or prognostic tool for calves affected by bovine respiratory disease. On arrival, calves were randomly assigned to one of two dietary energy levels (0.85 or 1.07 Mcal of NEg/kg of DM) and one of two dietary starch levels (34 or 48% of dietary ME from starch; n = 5 pens/treatment). All calves were weighed, and plasma and serum samples were collected from a subset of animals (n = 6 calves/pen; 30 calves/treatment) on d 0, 7, 14, 28, and 42 of the receiving period. This subset of calves (n = 120) was used for all subsequent analyses. Concentrations of fibrinogen (Fb), haptoglobin (Hp), and serum amyloid-A (SaA) were determined. In addition, samples were collected from the subset of calves when they received medical treatment and 7 d following treatment to measure serum concentrations of Hp and SaA. Serum concentrations of Fb, Hp, and SaA did not differ among dietary treatments, but decreased (P < 0.03) as day of the receiving period increased. Fibrinogen (P < 0.001) and the ratio of Fb:total blood protein were greater (P < 0.003) in calves treated multiple times than in calves never treated or treated once for bovine respiratory disease. In addition, on d 0 and 7, Hp concentration increased (antimicrobial treatment x day interaction, P < 0.03) as the number of antimicrobial treatments increased, and was greater on d 14 and 28 in calves treated multiple times than in calves never treated or treated once. Haptoglobin concentration was greater (P < 0.05) in calves on medical treatment days compared with recovery days (7 d after medical treatment). Although diet seemed to have little effect on acute-phase protein response, these results suggest that haptoglobin may be useful as a diagnostic tool to make management decisions regarding treatment protocols for calves with bovine respiratory disease.
authors.affiliation: Department of Animal Science, Oklahoma State University, Stillwater 74078, USA.
authors.forename: B A
authors.initials: BA
authors.lastname: Berry
authors.forename: A W
authors.initials: AW
authors.lastname: Confer
authors.forename: C R
authors.initials: CR
authors.lastname: Krehbiel
authors.forename: D R
authors.initials: DR
authors.lastname: Gill
authors.forename: R A
authors.initials: RA
authors.lastname: Smith
authors.forename: M
authors.initials: M
authors.lastname: Montelongo
mesh_terms: D000209:Acute-Phase Proteins / Q000378:metabolism*; D000827:Animal Welfare; D000818:Animals; D002417:Cattle / Q000097:blood* / Q000254:growth & development; D002418:Cattle Diseases / Q000097:blood / Q000175:diagnosis / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D002149:Energy Intake / Q000502:physiology*; D005340:Fibrinogen / Q000032:analysis; D006242:Haptoglobins / Q000032:analysis; D008297:Male; D011897:Random Allocation; D012140:Respiratory Tract Diseases / Q000097:blood / Q000175:diagnosis / Q000378:metabolism / Q000662:veterinary; D000685:Serum Amyloid A Protein / Q000378:metabolism; D013213:Starch / Q000008:administration & dosage* / Q000378:metabolism; D013312:Stress, Physiological / Q000097:blood / Q000175:diagnosis / Q000378:metabolism / Q000662:veterinary
chemical_list: D000209:Acute-Phase Proteins; D006242:Haptoglobins; D000685:Serum Amyloid A Protein; D005340:Fibrinogen; D013213:Starch