|Roberts, Andrew - Andy|
Submitted to: Professional Animal Scientist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/15/2008
Publication Date: 6/3/2008
Citation: Standley, T., Paterson, J., Skinner, K., Rainey, B., Roberts, A.J., Geary, T.W., Smith, G., White, R. 2008. The Use of an Experimental Vaccine in Gestating Beef Cows to Reduce the Shedding of Escherichia coli O157:H7 in the Newborn Calf. Professional Animal Scientist 24:260-263. Interpretive Summary: Reducing the amount of E. coli O157:H7 shed through animal feces will be useful in preventing contamination of meat. Beef cows in the last trimester of pregnancy were used to determine if vaccinating against E. coli O157:H7 would increase antibody titers in the serum and also result in the transfer of these antibodies to the neonatal calf. Results from this research indicate that vaccinating the gestating cow with an experimental vaccine against E. coli O157:H7 increased antibody titers against this organism in both the cow and suckling calf. Because animals in this study exhibited little or no fecal shedding of 0157:H7, efficacy of the vaccine in reducing shedding could not be evaluated.
Technical Abstract: Beef cows in the last trimester of pregnancy were used to determine if vaccinating against E. coli O157:H7 would increase antibody titers in the serum and also result in the transfer of these antibodies to the neonatal calf. Seventy-one cows were vaccinated 30 d prior to parturition with an experimental vaccine and then commingled with 66 non-vaccinated cows. Cow fecal and venous blood samples were collected at trial initiation and again ~14 d after parturition. Calf feces and serum were collected at ~14 d after parturition and 60 d later. The serum was analyzed for antibody titers to E. coli O157:H7 while the prevalence of E. coli O157:H7 in feces was determined by the Barkocy-Gallagher procedure. Initial cow antibody titers to O157:H7 were not different (P=0.50) between treatments but by parturition the antibody titers for O157:H7 in vaccinated cows were ten times higher (P<0.001) than for control cows (917 vs. 83). The serum titers for calves suckling vaccinated cows were higher (P<0.001) than control calves (1485 vs.135) at ~14 d after calving. By 60 d, titer levels were still higher (P<0.001) for calves suckling vaccinated cows. Initial fecal O157:H7 concentrations for cows were negative for both treatments and remained low. There were no differences in fecal O157:H7 at 60 d post partum among 14 calves; less than 5% of calves were shedding. Results suggest that vaccinating gestating cows for E. coli O157:H7 resulted in elevated antibody titers cows and these antibodies transferred to the calf.