In this study we evaluate the efficacy of five
vaccine formulations containing different combinations of
proteins (FimH;
leukotoxin, LKT; and
pyolysin, PLO) and/or inactivated whole cells (Escherichia coli, Fusobacterium necrophorum, and Trueperella pyogenes) in preventing postpartum
uterine diseases. Inactivated whole cells were produced using two genetically distinct strains of each bacterial species (E. coli, F. necrophorum, and T. pyogenes). FimH and PLO subunits were produced using
recombinant protein expression, and LKT was recovered from culturing a wild F. necrophorum strain. Three subcutaneous
vaccines were formulated:
Vaccine 1 was composed of inactivated bacterial whole cells and
proteins;
Vaccine 2 was composed of
proteins only; and
Vaccine 3 was composed of inactivated bacterial whole cells only. Two intravaginal
vaccines were formulated:
Vaccine 4 was composed of inactivated bacterial whole cells and
proteins; and
Vaccine 5 was composed of PLO and LKT. To evaluate
vaccine efficacy, a randomized clinical trial was conducted at a commercial dairy farm; 371 spring heifers were allocated randomly into one of six different treatments groups: control,
Vaccine 1,
Vaccine 2,
Vaccine 3,
Vaccine 4 and
Vaccine 5. Late pregnant heifers assigned to one of the
vaccine groups were each vaccinated twice: at 230 and 260 days of pregnancy. When
vaccines were evaluated grouped as subcutaneous and intravaginal, the subcutaneous ones were found to significantly reduce the incidence of puerperal metritis. Additionally, subcutaneous vaccination significantly reduced rectal temperature at 6±1 days in milk. Reproduction was improved for cows that received subcutaneous
vaccines. In general, vaccination induced a significant increase in serum
IgG titers against all
antigens, with subcutaneous vaccination again being more effective. In conclusion, subcutaneous vaccination with inactivated bacterial components and/or
protein subunits of E. coli, F. necrophorum and T. pyogenes can prevent puerperal metritis during the first lactation of dairy cows, leading to improved reproduction.