Pregnant cows were injected I / M two times at 6 -8 weeks before the expected time of parturition and again 3 to 4 weeks later, with a formalized killed whole cell bacterin containing enter toxigenic E. coli K99. Immunoglobulin concentration levels were measured in plasma of vaccinated cows prevaccination, post first dose of vaccine immunoglobulin levels were increased to 38.875, 3.190, 0.594, 14.2, 15.308 mg / ml compared to 22.35, 2.394, 0.258, 10.750, 8.773 for plasma IgG, IgM, IgA, IgG1, IgG2 of non-vaccinated control cows respectively.