Effects of dietary energy and starch concentrations for newly received feedlot calves: II. Acute-phase protein response1,2

• Published in: Journal of animal science 2004-03, Vol.82 (3), p.845-850
• Main Authors: Berry, B. A., Confer, A. W., Krehbiel, C. R., Gill, D. R., Smith, R. A., Montelongo, M.
• Format: Article
• Language: English
• Subjects: Bovine spongiform encephalopathy; Carbohydrates; Cattle; Diet; Energy; Nutrition; Proteins
• ISSN: 0021-8812; 1525-3163
• DOI: 10.1093/ansci/82.3.845

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 NE^sub g^/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 mea m 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 O and 7, Hp concentration increased (antimicrobial treatment × 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. [PUBLICATION ABSTRACT] Key Words: Acute-phase Proteins, Bovine Respiratory Disease, Energy, Receiving Calves, Starch