Abstract
To evaluate the immune response in calves with pneumonia, serum tumor necrosis factor (TNF) and peripheral leukocyte population were analyzed in 29 calves with naturally occurring pneumonia. The calves with pneumonia were divided into two groups: severe pneumonia (group 1, n=12) and mild pneumonia (group 2, n=17). In the group 1, all showed marked clinical signs such as polypnea, coughing and rales. The arterial pH and pO2 levels in group 1 were significantly lower than that in group 2. The serum TNF activity in group 1 tended to be higher than in group 2. Significant decreases in the numbers of CD3+, CD4+and CD8+T cells were observed in group 1 compared to group 2. There were significant relationships between CD3+T cells number and pO2, serum TNF activity and CD4+T cells number, respectively. These results indicated that serum TNF activity and leukocyte population were related to the pathophysiological condition in calves with pneumonia.
