Summary 



1 . It has been demonstrated that mass immunization of young chicks 

 with the l^i strain of Newcastle virus, employing spray techniques, is a 

 safe method, and will produce sufficient immunity to withstand 10 min- 

 imum lethal doses of Boney Newcastle disease challenge virus at approx- 

 imately 12 to 16 weeks of age. 



2. It has been demonstrated that there is no apparent interference in- 

 volved in the combination of Blacksburg strain of Newcastle and the UNH 

 strain of infectious bronchitis viruses when such a combination vaccine is 

 administered to young chicks utilizing the spray method of mass im- 

 munization. 



3. It has been demonstrated that mass immunization by the spray 

 methods of a combined Newcastle-bronchitis vaccine is a safe method of 

 vaccination and will produce sufficient immunity to withstand 10 minimum 

 lethal doses of Boney Newcastle challenge and 1000 infective doses of field 

 strain of infectiou.s bronchitis up to approximately 12 to 16 weeks of age. 



4. It has been demonstrated that the spray method of mass immun- 

 ization is an easy and rapid method of vaccination. One man may vaccinate 

 up to 10.000 chicks per hour, using this method, depending on brooding 

 conditions. 



References 



1. Bankowski, R. A. 1950. Further Studies /;/ vitro Cultivated Pheuinoenoeqhalitis 



(Newcastle Disease) Virus and Its Use as a Vaccine, Vet. Med. 45: 322-327. 



2. Crawley, J. F. 1953. Spray Immunization of Broiler Chicks with Combined 



Bronchitis — Newcastle Disease Live \'irus Vaccines. 25th .Annual Conf. 

 Lab. \\'orkers Pullorum Disease Control. 



3. Crawley, J. F. and Fahey, J. E. 1954. The Spray Method for Bronchitis and 



Newcastle Disease Vaccination. Southwest Vet. 7. 



4. Fabricant, J. 1951. Studies on the Diagnosis of Newcastle Disease and In- 



fectious Bronchitis of Fowls. IV. The Use of the S N Test in Diagnosis 

 of Infectious Bronchitis. Cornell Vet. 41: 68-80. 



5. Hitchner, S. B. 1950. Further Observations on a Virus of Low Virulence 



for Immunizing Fowls .Against Newcastle Disease (Avian Pneumoencc- 

 phalitis). Cornell Vet. 40: 60-70. 



6. Hitchner, S. B. and Reising, G. 1952. Flock Vaccination for Newcastle Di- 



sease by Atomization of the Bi Strain of Virus. Proc. Bk. Am. Vet. Med. 

 Assoc: 258-264. 



7. Hitchner, S. B., and Johnson. E. P. 1948. A Virus of Low Virulence for 



Immunizing Fowls .\gainst Newcastle Disease (Avian Pneumoeno- 

 cephalitis). \'ct. Med. 43: 525-530. 



8. Jungherr, E. L. and Terrell, N. L. 1948. Naturally Acquired Passive Ini- 



munity to Infectious Bronchitis in Chicks. Am. Jour. Vet. Res. 9:201-205. 



9. Luginbuhl. R. E. 1952. Studies on Serologic Diagnosis and Immunization of 



Avian Infectious Bronchitis. Master's Thesis, University of Connecticut, 

 Storrs, Connecticut. 



10. Markham. F. S., Bottorff, C. A., and Cox, H. R. 1951. The Conjunctival 

 .Application of Newcastle Disease Vaccine (Intranasal Type) in Paren- 

 tally Immune and Susceptible Chicks. Cornell Vet. 41: 267-282. 



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