The Research On Chicken Kidney Type Infectious Bronchitis Live Vaccine (SK9 Strain)

In order to prevent chicken kidney type infectious bronchitis, we have screened strain SK9 virus and tested its safety, stability, immunity, specificity, purity, gene sequence, and so on. We prepared vaccine with SK9 virus and compared SK9 vaccine with other vaccines, and we found that SK9 is much better than other viruses in immunity and intercross protection ratio. The research showed that SK9 is a good virus vaccine strain for kidney type infectious bronchitis.The research is consisted of these parts:1. We compared several types of the infectious bronchitis virus strains and found that SK9 virus can prevent kidney and respiratory type infectious bronchitis disease. The virulent virus challenge test had the same result.2. The safety, immunity, specificity and purity test on SK9 showed that SK9 is safe, effective and good immunity, without mycoplasma and extrinsic virus pollution. SK9 can specially prevent kidney type infectious bronchitis and be safe in virulent virus challenge test.3. The result of virulence stability of infectious bronchitis strain SK9 virus showed that virus titer is increased slightly from 10^6.25EID₅₀/0.1ml to 10^7.0EID₍50_/0.1ml after being immediately transferred 10 passages in chicken embryos, its safety is unchanged as its virulence weakened but its titer increased during this process. We inoculated high titer SK9 virus which being regressed 6 passages in chickling, and found no disease, no pneumal hypertension and hemorrhage, no kidney swelling and urate deposition. SK9 is stable and safe after being regressed 6 passages in chickling. The result is SK9 is very good on virulence.4. The mid-trial production: 0404001-0404003 lots vaccines is pure on bacteria, fungi, mycoplasma and extrinsic virus test, good on stability and safety. The production and inspection results showed that the production process is mature, stable and suitable for large scale production. The customers were satisfied with the vaccine because SK9 is good in prevention of kidney type and respiratory type infectious bronchitis, also good without harmful reaction on chicken's productivity. They wish us to provide SK9 vaccine with safety and good immunity usually.