title: Effect of shipping and chromium supplementation on performance, immune response, and disease resistance of steers.
abstract: Forty-eight Angus crossbred steers (263 +/- 2 kg initial BW) were blocked by weight and randomly assigned within weight group to treatment. Treatments consisted of control or .4 mg of supplemental Cr as Cr-nicotinic acid complex/kg of DM. Steers were fed diets containing 90% corn silage (DM basis) and 10% of a soybean meal-mineral-vitamin supplement. After 56 d on the dietary treatment, half of the steers in each treatment were transported 343 km and unloaded in an unfamiliar location. The next day, d 58, shipped steers were returned to the feedlot (50 km). On d 58 after shipped steers were returned to the feedlot, all steers were inoculated with infectious bovine rhinotracheitis virus (IBRV) intranasally. Average daily gain from d 0 to 80 was increased (P < .10) by supplemental Cr. There was a shipping x time interaction for serum cortisol concentrations. Shipping increased (P < .02) serum cortisol on d 58, but 7 d after transport there were no effects of shipping on serum cortisol. Transportation increased (P < .05) the ratio of neutrophils to lymphocytes. Supplemental Cr did not affect rectal temperature after the IBRV challenge or the antibody response to IBRV or porcine red blood cells. Immunoglobulin G antibody response to porcine red blood cells was decreased (P < .09) by shipping. Supplemental Cr as Cr-nicotinic acid improved ADG of growing steers, regardless of whether they had been stressed by shipping. Supplemental Cr did not affect any of the immune responses that were measured.
authors.affiliation: Department of Animal Science and Interdepartmental Nutrition Program, North Carolina State University, Raleigh 27695-7621, USA.
authors.forename: E B
authors.initials: EB
authors.lastname: Kegley
authors.forename: J W
authors.initials: JW
authors.lastname: Spears
authors.forename: T T
authors.initials: TT
authors.lastname: Brown
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis* / Q000276:immunology; D001786:Blood Glucose / Q000032:analysis; D001831:Body Temperature / Q000502:physiology; D002417:Cattle / Q000097:blood / Q000254:growth & development* / Q000276:immunology*; D002857:Chromium / Q000008:administration & dosage / Q000494:pharmacology*; D005508:Food Deprivation / Q000502:physiology; D005527:Food, Fortified; D007242:Herpesvirus 1, Bovine / Q000276:immunology; D006854:Hydrocortisone / Q000097:blood; D007113:Immunity, Innate; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D007241:Infectious Bovine Rhinotracheitis / Q000276:immunology / Q000517:prevention & control; D008297:Male; D011897:Random Allocation; D014186:Transportation; D014868:Water Deprivation / Q000502:physiology
chemical_list: D000914:Antibodies, Viral; D001786:Blood Glucose; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D002857:Chromium; D006854:Hydrocortisone