Attenuated mutant newcastle disease virus strains for in ovo vaccination, method for preparing and their use

摘要

The present invention relates to new attenuated mutant New Castle's disease La SotaNewcastle disease virus strains suitable for in ovo vaccination of avian species comprising a mutation in the gene sequences encoding the HN and/or F glycoproteins of said virus. Furthermore, the invention relates to a vaccine composition comprising said attenuated mutant Newcastle's disease La Sota virus strain, and to the use thereof for the preparation of a vaccine for in ovo vaccination of avian species against Newcastle's disease.