Virological and Immunological Diagnosis of Bovine Viral Diarrhea Virus in Rabbits

1 Virology Department, Faculty of Veterinary Medicine, Zagazig University, 44511, Egypt 2 Animal Reproduction Research Institute, Giza, Egypt. Abstract Bovine viral diarrhea (BVD) is a viral infectious disease of cattle. Other animals may act as reservoirs of BVDV; Rabbits are wide range in many countries, frequently existing close to farm animals. Recent studies revealed that BVDV propagated in rabbits through different routes of infections. Thus, New Zealand White rabbits were infected with two biotypes of BVDV (NADL and 890) through different routes (intravenous, nasal and oral). No clinical signs appeared on the infected rabbits. On the other hand, the lymphoid organs (GALF) of ileum of rabbits of BVDV infected groups and sacrificed at day five post infections showed depletion in the population of lymphocytes in the center of some lymphoid follicles. By RT-PCR some buffy coat samples and most organ samples in all exposed groups were virus positive at day five post infection, however samples of mock-infected control group remained negative. Antibodies development was observed in all groups infected animals, while in mock-infected control group, there was not production of antibodies. Innate immunity was detected by assessment of lysozyme and nitric oxide concentrations. There was an increase in lysozyme and nitric oxide concentrations in BVDV exposed groups when compared with mock infected group after day three as a defense mechanism of the host against the virus. Conclusion, these results indicates that rabbits are susceptible to infection by BVDV biotypes without clinical signs and lesions.