FIG. 3.

Levels of Hp in the sera of calves experimentally infected with ncpBVDV detected by using a commercial test kit. This enzymatic test is based on the peroxidase activity of hemoglobin which is preserved at low pH after binding of Hp. The detection limit of the test was determined to be 45 μg/ml. The Hp levels for the individual calves and the mean values for the six calves are depicted from day 18 before infection (day −18) through day 0 (day of virus inoculation) and up to day 24 postinfection.