Bovine Virus Diarrhea Vaccine, Killed Virus.

CFR · 2024-01-01 · US · Title 9

Bovine Virus Diarrhea Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed virus which has been established as pure, safe, and immunogenic shall be used for preparing seed cultures for vaccine production. All serials of vaccine shall be prepared from the first through the fifth passage from the Master Seed. (a) The Master Seed shall meet the applicable general requirements prescribed in § 113.200 and the requirements of this section. (b) The immunogenicity of vaccine prepared from the Master Seed in accordance with the Outline of Production shall be established by a method acceptable to the Animal and Plant Health Inspection Service. Vaccine used for this test shall be at the highest passage from the Master Seed and at the minimum preinactivation titer provided in the Outline of Production. (c) (1) (2) (i) Eight bovine virus diarrhea susceptible calves (five vaccinates and three controls) shall be used as test animals. Individual serum samples shall be collected, inactivated, and individually tested for neutralizing antibody. (ii) A constant virus decreasing serum neutralization test in cell culture using 50-300 TCID50 of virus shall be used. Calves shall be considered susceptible if there is no neutralization at 1:2 final serum dilution. Other tests of equal sensitivity approved by the Animal and Plant Health Inspection Service may be used. (iii) The five calves used as vaccinates shall be administered one dose of vaccine as recom

official document · source cfr-2024 · id 9:§ 113.215