HERD HEALTH
PIH-30
pork industry handbook
COOPERATIVE EXTENSION SERVICE • PURDUE UNIVERSITY • WEST LAFAYETTE, INDIANA
Enteric Colibacillosis of Newborn Pigs
Authors
Erwin M. Kohler, Ohio State University, O.A.R.D.C., Wooster, Ohio
Harley Moon, USDA, Ames, Iowa
Reviewers
Dwight Armstrong, North Carolina State University
Gerald Bernard, New Vienna, Ohio
Names such as E. coli diarrhea or scours, baby pig scours, and colibacillosis are popularly used today to label an intestinal disorder of newborn swine characterized by large amounts of liquid feces. Research has shown that some strains of Escherichia coli bacteria can cause such intestinal disorders, but there are also other bacteria and viruses which can cause diseases with some more or less similar clinical signs. Within any herd, these different infectious agents may cause disorders concurrently or sequentially. This summary was prepared specifically to help the readers understand some of the current knowledge about 
E. coli infections.

It is often necessary to conduct laboratory tests to establish an accurate diagnosis. Properly collected specimens from carefully selected pigs are required for meaningful diagnostic efforts. Even then it may be difficult to establish the diagnosis for a particular episode of diarrhea. Too frequently, costly chemotherapeutic agents are administered on the assumption that the diarrhea is being caused by E. coli when, in fact, the disease is being caused by a virus (such as TGE or rotavirus) or another microorganism that is completely unaffected by the drugs used.

Cause
E. coli are normal inhabitants of the intestinal tract and are present in large numbers in the large intestine but not the small intestine of normal animals. However, certain strains are classed as enteropathogenic, meaning that they produce disease by developing in the intestine without necessarily invading the other tissues of the body. Enteropathogenic E. coli are found throughout the world; there is probably at least one strain in each herd. It is important to understand that the incidence of disease caused by enteropathogenic E. coli is greatly influenced by the management of herd and
facilities. Such strains of E. coli have the ability to propagate rapidly in the small intestine. Additionally, these strains produce toxins (enterotoxins) which cause, massive fluid losses from the body. The amount of fluid and electrolytes in the small intestine soon exceeds the absorptive capacity of the intestine. Consequently, large quantities of pale yellow, watery feces are passed. The fluids are lost at such a rapid rate that the pig becomes dehydrated and also develops acidosis because a large proportion of the electrolytes lost are basic. The liquid feces are usually quite alkaline. The pigs usually are thirsty and continue to nurse until they become too weak and depressed to do so.

This fact sheet is directed primarily to neonatal enteric colibacillosis, which is diarrhea caused by enteropathogenic E. coli in pigs less than 7 days old A number of host and environmental factors affect the incidence of E. coli-caused diarrhea of newborn pigs. The stomach and intestine of pigs are quickly flooded with bacteria immediately after birth. Many of these are “harmless," but if large numbers of enteropathogenic E. coli are present, many pigs will probably be infected immediately after birth.

Large numbers of E. coli are usually present in the immediate environment whenever it is dirty and wet, the ventilation is poor, and the humidity is high. However, the most important source of infection is other young pigs with E. coli diarrhea. These pigs will shed up to 1 billion E. coli/cc. of the liquid feces.

Temperature is probably the most important of all the environmental influences on the well-being of the pigs. It is also one of the easiest to control in modern farrowing facilities. Young pigs are extremely sensitive to chilling, and this stressor lowers the resistance of pigs to infections including E. coli.
Cooperative Extension Work in Agriculture and Home Economics, State of Indiana, Purdue University and U. S. Department of Agriculture Cooperating. H. G. Diesslin, Director, West Lafayette, IN. Issued in furtherance of the Acts of May 8 and June 30, 1914. It is the policy of the Cooperative Extension Service of Purdue University that all persons shall have equal opportunity and access to its programs and facilities without regard to race, color, sex, religion, national origin, age or handicap.