Serologic evidence of bovine viral diarrhea virus in free-ranging rabbits from Germany

From 1993 to 1995, 100 blood samples and 97 spleen samples of free-ranging rabbits (Oryctolagus cuniculus) from northern Germany were tested for prevalence of different bovine viral diarrhea virus (BVDV) antibodies and BVDV antigen, respectively. Forty sera (40%) were positive for antibodies to one or more of three cytopathogenic BVDV strains (NADL, Grub 313/83, and roe deer isolate SH9/11). Microneutralization test (NT) titers ranged from 5 to 13. Moreover, 13 of 35 NT positive sera also were positive by enzyme-linked immunosorbent assay for detection of anti-BVDV antibodies. Therefore, we assume that the rabbits either had passively acquired antibodies or had experienced natural infection with BVDV. Furthermore, 97 spleen samples were used for attempts to isolate BVDV and tested by reverse transcription polymerase chain reaction for viral nucleic acid using various protocols. Bovine viral diarrhea virus was not identified in these samples.