![]() ![]() After challenge at 21 or 49 days of age, both vaccines gave 100% protection against clinical disease. ![]() The serologic response after Vac 1 by using a subtype B-based enzyme-linked immunosorbent assay was significantly higher than that induced by Vac 2, even though the titer of the recommended dose had a higher titer than Vac 1. Vac 1 virus was detectable for at least 14 days after vaccination, and Vac 2 virus was detectable for at least 7 days after vaccination. Parameters compared were persistence of vaccine viruses, their ability to induce humoral antibody responses, and the protection they offered against virulent challenge. The chicks were challenged at 21 or 49 days of age with a virulent subtype B virus. Live attenuated subtype B avian metapneumovirus (aMPV) vaccines from two different commercial sources (Vac 1 and Vac 2) were used to vaccinate two groups of day-old specific-pathogen-free chicks. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |