초록 ▼

The present invention relates generally to modified microorganisms suitable for use as live in ovo vaccines for avian species. The live in ovo vaccines of the present invention are useful for inducing immunity before or immediately after hatching against a virulent form of the modified microorganism

The present invention relates generally to modified microorganisms suitable for use as live in ovo vaccines for avian species. The live in ovo vaccines of the present invention are useful for inducing immunity before or immediately after hatching against a virulent form of the modified microorganism or a microorganism immunologically related to the modified microorganism or a virulent organism or virus carrying an antigenic determinant expressed by the modified microorganism in the live vaccine. The subject live in ovo vaccines are particularly efficacious in enhancing the survival rate of newly-hatched poultry birds.

대표청구항 ▼

[ What is claimed is:] [1.]1. A method for immunizing an avian species against infection by a pathogenic Salmonella microorganism, said method comprising administering in ovo to an air sac of an egg an attenuated Salmonella microorganism which:(a) exhibits auxotrophy to one or more growth factors se

[ What is claimed is:] [1.]1. A method for immunizing an avian species against infection by a pathogenic Salmonella microorganism, said method comprising administering in ovo to an air sac of an egg an attenuated Salmonella microorganism which:(a) exhibits auxotrophy to one or more growth factors selected from the group consisting of phenylalanine, tyrosine, tryptophan and para-aminobenzoic acid such that it is incapableof growing on a minimal medium in the absence of said one or more growth factors; and(b) is capable of colonizing one or more tissues in an embryo prior to hatching in an amount and under conditions effective to induce an immune response in the embryo before or immediately after hatching against a virulent form of said attenuated Salmonella microorganism or a microorganism expressing an immunologically cross-reactive antigen.