EN
The cyprinid herpesvirus 3 (CyHV-3), genus Cyprinivirus, family Alloherpesviridae, order Herpesvirales, is the etiological agent of a lethal disease in common carp (Cyprinis carpio) and koi carp (Cyprinis carpio koi). Since its emergence in the early twenty-first century, diseases induced by CyHV-3 caused severe economic losses in common carp in Poland. The Inland Fisheries Institute in Olsztyn with the Faculty of Veterinary Medicine University of Warmia and Mazury in Olsztyn developed several methods for diagnosing and preventing CyHV-3 in carp culture. This study focuses on the impact of CyHV-3 on nonspecific humoral defense mechanisms following experimental infection and in pond culture. The results indicated that CyHV-3 decreases myeloperoxidase levels in neutrophils, lysozyme activity in pronephros and serum, and total immunoglobulin (Ig) levels in serum. The ceruloplasmine activity was statistically higher in sick carp as compared to the control carp that were free of CyHV-3. The present results suggest that CyHV-3 decreases the neutrophils, macrophages, and lymphocytes activities to produce nonspecific humoral factors.