Cross Protection Studies

Vaccination with Salmonella Gallinarum strain 9 R (rough) results in a good cross-immunity to Salmonella Enteritidis. Both strains belong to Group D in the Kauffman-White scheme.

Trial

Method

• Chickens vaccinated with Nobilis SG 9R and non-vaccinated controls were challenged with S. Enteritidis at 23 weeks of age.
• Cloacal swabs were cultured for S. Enteritidis at intervals post-challenge.
• Caecal contents were cultured at necropsy 14 days post-challenge.

Results

Shedding of S. Enteritidis was significantly reduced in vaccinated chickens.

Field experience

Cross-protection to S. Enteritidis was also confirmed in a large field study in The Netherlands.

• 80 commercial layer flocks, 2,2 million layers in total, with a high risk profile for S. Enteritidis infection were vaccinated with Nobilis SG 9R.
• 79 flocks remained Salmonella Enteritidis negative during the trial.
• During the same period 214 out of a total of 1845 unvaccinated flocks, at a low risk for Salmonella infection, tested Salmonella positive.

Conclusion

Vaccination with Nobilis SG 9R significantly reduced the level of Salmonella Enteritidis on the farms.