A description of new commercial and experimental vaccines for viral an
d bacterial diseases of cattle can be broadly divided into those used
for both beef and dairy cows and those used predominantly in dairy cat
tle. For both types of cattle, newer and experimental vaccines are dir
ected against several of the important viral (e.g., bovine herpesvirus
1, bovine viral diarrhea virus, bovine respiratory syncytial virus, p
arainfluenza type 3, and foot-and-mouth disease virus) and bacterial p
athogens (e.g., Pasteurella spp., Haemophilus somnus). The viral vacci
nes include gene-deleted, modified live, subunit, and peptide antigens
. Newer bacterial vaccines, particularly those for Pasteurella spp., a
re composed of either modified-live vaccines or bacterins supplemented
with toxoid or surface antigens. Haemophilus somnus vaccine research
has concentrated mainly on defining unique surface antigens. Novel dai
ry cow vaccines would include the lipopolysaccharide-core (J5) antigen
approach, which has been used for successful immunization against col
iform mastitis. Core antigen vaccines also have reduced calf mortality
from Gram-negative pathogens. Staphylococcal mastitis vaccines that c
ontain capsular antigens, toxoids, or the staphylococcal fibronectin r
eceptor are of active research interest. Vaccines against mastitis ind
uced by Streptococcus agalactiae and Streptococcus uberis also are are
as of intensive research. Delivery of multiple subunit antigens with o
ptimal immune response induction has led to the investigation of atten
uated heterologous viral and bacterial expression vectors such as bovi
ne herpesvirus 1, vaccinia, and Salmonella spp. This discussion also d
emonstrates that molecular biology is being used to advance bovine vac
cine technology.