London Swine Conference – Building Blocks for the Future 1-2 April 2004 141 CONTROLLING E. COLI IN THE WEANED PIG

Post weaning colibacillosis is a bacterial disease caused by certain types of Escherichia coli and primarily affects pigs in the period shortly after weaning. The diarrhea causes metabolic acidosis, electrolyte imbalance and dehydration which leads to increased death loss and reduced production efficiency. Economic losses are attributed to mortality and treatment costs of individual animals. Mortality may reach as high as 7%. A balanced approach to control has involved the simultaneous implementation of multiple interventions. There is strong scientific evidence for the use of antimicrobials. There is however little scientific evidence to support other best management practices. Control strategies have relied on empirical observation in the field. ETIOLOGY Escherichia coli (E. coli) are a group of gram negative flagellated bacteria that normally reside and multiply in the intestinal tract of all animals. E. coli normally increase in numbers during passage from the stomach through the duodenum, jejunum and ileum of the small intestine with the greatest numbers in the ileum. Some strains are hemolytic. Most virulenc