Acute phase response of sheep: changes in the concentrations of ceruloplasmin, fibrinogen, haptoglobin and the major blood cell types associated with pulmonary damage.

The concentrations of plasma ceruloplasmin, plasma fibrinogen, serum haptoglobin and the major cell types in blood together with liveweight changes were monitored during the acute phase response in sheep. Five control sheep, five sheep that underwent sham bronchial obstruction, and five sheep that developed pneumonia after bronchial obstruction were examined. Blood samples were taken and liveweights were recorded from four to six days before until 14 days after the surgical operations (sham and bronchial obstruction). The operations led to an acute phase response in the sheep and the development of pneumonia increased and sustained the response or led to a secondary response. Statistically significant changes observed in the blood of the sheep during the acute phase response included increased concentrations of plasma ceruloplasmin and plasma fibrinogen, depression of erythrocyte numbers and elevation of neutrophil numbers (means on day of maximum change as percentage of pretreatment values; 250 per cent, 400 per cent, 80 per cent and 200 per cent, respectively). Serum haptoglobin showed a pronounced and significant increase in concentration (over 6000 per cent of pretreatment values in some sheep). All three groups of sheep showed significant depression of liveweight after overnight confinement in the surgery but this was sustained for the period of the experiment only in the bronchial obstruction group. The results indicated that measurement of the concentrations of the three plasma proteins may be more useful in the diagnosis of tissue injury and infectious disease than the number of circulating neutrophils in sheep.