THE LEVEL OF DELAYED-HYPERSENSITIVITY AND PRIMARY IMMUNE-REACTION AFTER ADMINISTRATION OF INACTIVATED OIL IBR VACCINE TO GLUCANE-PREMEDICATED CALVES

The level of delayed skin hypersensitivity (DSH) to DNFB and of the pr imary immune reaction was evaluated in the calves immunized with an in activated oil IBR vaccine (V group) and in the calves premedicated wit h glucane (seven days before vaccine administration) and subsequently immunized with the mentioned vaccine (GV group). The DSH test did not reveal an alteration of cellular immunological reactivity in the calve s immunized with an inactivated oil IBR vaccine; after the vaccine adm inistration there was no significant difference in the DSH level from the value before vaccine administration nor in comparison with the val ue of control calves (K group), Tab. I. But in the immunized calves wh ich were glucane-premedicated (from Pleurotus ostreatus; 10 mg/kg l.w. ) a significantly higher DSH level was determined not only in comparis on with the initial value (P < 0.05) before glucane administration but also with the value of control calves (P < 0.05), Tab. I. The categor ization of calves according to the DSH level also points to the immuno modulating effect of glucane in this sense (Fig. 1); while the value o f skin test ranged from 3.6 to 6.5 mm in the highest percentage of the calves of V and K groups on the dates before and after administration of the mentioned preparations, a marked increase (on the date after a dministration) in the number of calves (from 22 to 67 %) with the valu e of skin test higher than 6.5 nun was observed in the calves of GV gr oup. The vaccine administration in itself (V group) did not induce the production of measurable amounts of serum IBR antibodies till day 14 after immunization. In the glucane-premedicated calves (GV group) the primary immune reaction began to appear with a week advance, i.e. as s oon as on day 7 after vaccination; in the second week the antibodies w ere demonstrated in 44 % of the examined calves with the average titre 1 : 6.2. In the third week of the experiment the serum antibodies wer e detected in 79 % of the calves of the V group (average titre 1 : 28. 4) and in 67 % of the calves of the GV group (average titre 1 : 13.3); the mentioned difference in the serum antibody concentration was not statistically significant. Then the antibody titre was decreasing in b oth groups of calves reaching almost the same values in the 4th week a fter vaccination (V group = 1 : 3.5; GV group = 1 : 4.4), Fig. 2.