Relationships between clinical and pathological signs of disease in calves infected with Mannheimia (Pasteurella) haemolytica type A1.

Respiratory disease was induced in 16 calves, and the terminal clinical signs of disease and postmortem pathological observations were recorded. By Spearman's correlation coefficient, the respiratory rate, rectal temperature and clinical scores of the calves were significantly correlated with the extent of lung consolidation. The respiratory rate was the clinical sign most consistently correlated with the other clinical and pathological signs of respiratory disease.