Swine buffy coat culture: an aid to the laboratory diagnosis of hog cholera.

A 2-step technique for the isolation of hog cholera (HC) virus consisting of an initial culture on buffy coat (BC) cultures and subinoculation to a pig kidney cell line (PK-15) was described. By this technique, HC virus was confirmed in specimens from 65 herds in which the conventional cell culture isolation technique failed. The herds were located in 20 states and Puerto Rico. Specimens from 29 of the 65 herds were inoculated into specific-pathogen-free (SPF) pigs. Hog cholera virus was recovered from 27 of the test pigs. The 2 pigs from which virus was not recovered had signs of acute infection and, on necropsy, had gross lesions of HC infection.