Evaluation of egg yolk immunoglobulins in passive protection of post-weaned pigs against enterotoxigenic K88+ Escherichia coli.

摘要

Post-weaning E. coli diarrhea is a major cause of mortality and morbidity in Ontario swine nurseries. Commercial products containing egg yolk antibodies specific for the control of K88+ E. coli diarrhea have been used in an attempt to prevent disease loss. This study evaluated the use of an egg yolk antibody product, incorporated into nursery feed, on two farms where K88+ E. coli diarrhea was identified as a problem. There was no difference between treatment and control pigs on either farm based on diarrhea prevalence and mortality. Challenge doses of 5 x 1011 CFU of K88+ E. coli administered orally to weaned pigs produced diarrhea. Egg yolk antibody in dosages of 0.32% and 3.2% in the feed were not successful in preventing post-weaning diarrhea. An ELISA for K88 antibodies in gut content failed to detect antibody activity. It is likely that a combination of low levels of antibody and damage from stomach acid and gastrointestinal enzyme activity resulted in the failure of egg yolk immunoglobulins to protect post-weaned pigs against enterotoxigenic E. coli infection.