Effect of prepartum vaccination with K99 Escherichia coli vaccine on maternal and calf blood antibody concentration and calf health.

One hundred and two dry, pregnant Holstein cows were identified alternately as vaccinated or nonvaccinated (Group 0) animals. Vaccinated cows were scheduled for vaccination at 6 and 3 wk prior to expected calving date with Vicogen, a commercial vaccine produced for the prevention of calf scours caused by enteropathogenic Escherichia coli that possess the K99 antigen. Group 1 included cows that were less than 6 wk from freshening when the experiment started and, therefore, received only one vaccination and cows that received two vaccinations with less than 5 days between the second vaccination and freshening. Those cows with interval between the second vaccination and parturition greater than 5 days were classified as Group 2. Soon after birth, each calf was given 2 liters of colostrum from its dam. For at least 3 days, and longer when available, calves from control cows received pooled colostrum from control cows and calves from vaccinated cows received pooled colostrum from vaccinated cows. Anti-K99 antibody titers were determined by an agglutination test on blood from cows and calves and on colostrum. Other measurements were made by standard procedures. Results from Groups 0, 1, and 2 were cow blood titer at freshening 21, 355, 306; calf total plasma protein at 24 h of age 6.45, 6.31, 6.22; calf packed cell volume at 24 h of age 32.9, 30.0, 30.2; calf blood titer at 24 h of age 34, 762, 1114; colostrum titer 74, 1637, 3404. For 93 calves, mortality was 10.6, 11.1, and 7.1%.(ABSTRACT TRUNCATED AT 250 WORDS)