| abstract |
This disclosure provides attenuated Histophilus somni strains, compositions comprising same, and methods of production and use thereof. The attenuated strains may express lower or no levels of various virulence-associated genes, relative to the corresponding pathogenic bacteria Advantageously, the attenuated Histophilus somni strains may be administered orally, intranasally, intra-tracheally, or subcutaneously. |