|Carroll, Jeffery - Jeff Carroll|
|Dailey, Jeffery - Jeff|
Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: 12/15/2008
Publication Date: 2/2/2009
Citation: Behrends, S., Carroll, J.A., Buntyn, J., Dailey, J.W., Hulbert, L.E., Ballou, M., Schmidt, T. Evaluation of immunological and physiological parameters associated with an infectious bovine rhinotracheitis viral challenge in beef steers [abstract]. Annual meeting of the Southern Section of American Society of Animal Science in Atlanta, GA, on Jan 31 - Feb 4, 2009. Journal of Animal Science. 87(Supplement 2):22. Abstract #66.
Technical Abstract: To evaluate the effects infectious bovine rhinotracheitis virus (IBRV) has on immunological and physiological parameters of cattle; 12 Angus crossbred steers (228.82 ± 22.15 kg) were randomly assigned to either a Control group or an IBRV challenged group. Prior to the challenge, steers were fitted with an indwelling rectal probe, weights were recorded, and a blood sample was obtained. On day 0, IBRV steers received an intra-nasal dose of IBRV (2 ml/nostril; Cooper strain, 1 X 1 to 10 million PFU) and control steers received an intra-nasal dose of saline (2 ml/nostril). After the challenge, steers were returned to their isolated paddocks for approximately 73 hours. Challenged steers were placed in a paddock which was isolated from the control cattle as well as all other cattle located on the research farm. During the first 48 hours post challenge, blood was collected via a single venipuncture of the jugular vein. At 72 hours post challenge, steers were fitted with temporary indwelling jugular catheters, fitted with heart rate monitors, and then moved to individual metabolism stanchions. Blood samples were intensively collected for a total of 12 days. Serum was analyzed for interleukin-1 beta (IL-1), -2, -4, and -6, interferon-gamma (IFN), tumor necrosis factor-alpha (TNF), and cortisol. Interleukin-1, 2, and 4 concentrations were extremely low (less than 20 pg/ml) in challenged animals. Cortisol, IFN, TNF, and IL-6 all increased in challenged animals. Cortisol and IFN had similar response patterns (r = 0.11, p < 0.05) in IBRV steers. All IBRV steers had increased concentrations of cortisol and IFN starting around day 2, peaking on day 4, and tapering off around day 6. Only half of the IBRV cattle (n = 4) had increased concentrations of TNF starting around day 5 and tapering off around day 7 and half of those IBRV steers (n = 2) had increased concentration of IL-6. While the objective of this trial were to identify the cytokine and endocrine response of cattle infected with IBRV, we hypothesize that potential treatment effects may have been masked due to environmental constraints. Regardless of the environmental effects it appears that IFN 'and cortisol could potentially play important roles in the febrile response associated with cattle infected with IBRV.