| Summary |
Secondary SPF pigs with 5 weeks of age were infected experimentally with 2 isolates of hog cholera virus (HCV) obtained from 2 outbreaks between 1993~ 1994 via oronasal route. Similar gross lesion to the recent cases, such as spleen infarction and peripheral hemorrhage of lymph nodes were not really seen. Histopathological changes were characterized by depletion of mature lymphocytes and proliferation of reticular endothelial cells. Nonsuppurative encephalitis was not so evident as that caused by other viral diseases and not distinguishable from that caused by septicemia salmonellosis. HCV could be recovered from the tissues being tested of all pigs sooner or later. However, tonsil, mesenteric lymph node, and inguinal lymph node were the targets where the virus could be isolated earlistly and consistently by cell culture and PCR technique. Diphasic febrile reaction, a typical reaction of LPC-China strain, was not observed in the rabbits infected by 94-4 and 859 strains. Based on the findings of histopahtology, virus isolation, PCR and rabbit reponse were realized that these 2 field viruses are not virulent strain or LPC-china strain.
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