| Abstrakt: |
Efforts are being made at the National Veterinary Services Laboratories to reduce in vivo testing of USDA licensed veterinary vaccines. A hemagglutination test for determining potency of killed parvovirus vaccine is currently being used for canine and swine adjuvanted and nonadjuvanted products; a serum neutralization inhibition test (SNIT) is being developed for potency testing of killed adjuvanted infectious bovine rhinotracheitis (IBR), bovine virus diarrhea (BVD) and parainfluenza (PI3) vaccines: and a tissue culture titration method for live avian encephalomyelitis virus vaccine is being pursued as a replacement for the old hatch-out chick embryo titration method. Difficulties in separating the antigen from oil emulsion products are preventing significant advances in developing in vitro testing procedures for poultry killed-virus vaccines. |
