Evaluation of breath biomarkers and serum haptoglobin concentration for diagnosis of bovine respiratory disease in heifers newly arrived at a feedlot.

Objective: To evaluate exhaled N(2)O (eN(2)O), exhaled CO (eCO), and serum haptoglobin concentrations as diagnostic criteria for bovine respiratory disease (BRD) and determine whether a combination of biomarkers would be useful for predicting health outcomes of heifer calves.

Animals: 337 heifer calves newly arrived at a feedlot.

Procedures: Body weights, serum haptoglobin concentrations, and rumen temperatures were determined.