Baby pig diarrhea continues to be a big production headache in many operations. A host of traditional pathogens still exist, buy health is complicated by a whole new set of viral and bacterial pathogens.

Viruses still cause major problems. The incidence of transmissible gastroenteritis (TGE) has decreased in our practice area. Rotavirus has been diagnosed more frequently, but it is often in combination with other pathogens, leaving its role open for debate.

Bacteria such as Escherichia colibacillosis (E. coli) and Clostridium perfringens Type C have been diagnosed for more than 35 years. They can cause impressive death losses and severe production losses if left untreated.

Clostridium perfringens Type C causes a severe hemorrhagic (purplish) necrotic (rotten) intestinal tract that has characteristic lesions upon postmortems of pigs.

The pathogenic lesions are caused by an enterotoxin that can cause significant death losses. Early diagnosis, prevention and treatment programs need to be in place for effective control.

Recently, veterinarians and laboratory diagnosticians have diagnosed a new strain of Clostridium perfringens Type A. This presents a very different clinical picture than Type C.

Type A causes a secretory diarrhea with the enterotoxins causing more subtle pathologic changes. The enterotoxins released are different types than with the Type C and postmortems of affected pigs show thin-walled, yellowish intestines, without the bloody, necrotic look of Clostridium perfringens Type C.

Type A is more responsive to antibiotic therapy than Type C but is more difficult to treat than many E. coli cases of diarrhea.

Most Common Cause E. coli is a bacterial disease that can affect all ages of pigs from neonates under 5 days of age to postweaning pigs that have diarrhea and sudden death loss. E. coli is the most important and most common cause of piglet diarrhea identified by diagnostic laboratories and veterinary practitioners.

E. coli also produces enterotoxins that affect the intestines of pigs causing a secretory diarrhea. These enterotoxins can cause significant death loss and are responsible for most of the pathogenic problems associated with E. coli diarrhea.

Case Study No. 1 I was called to a 1,500-sow, farrow-to-wean operation. This was a newly constructed facility with an excellent environment and good management.

Two years after the start-up, many litters experienced slight diarrhea at 2 to 4 days of age. Preweaning mortality increased from 9% to more than 14%, and the growth of many pigs was stunted. Piglets had a watery diarrhea and were gaunt and unthrifty. Piglets were dehydrated and had pasty fecal stains on their hair coats.

They seemed to respond to antibiotic therapy of ceftiofur (Pharmacia & Upjohn) and other antibiotics. Necropsies on piglets showed a thin-walled intestinal tract with lots of watery fluid.

Samples were submitted to a laboratory for diagnostic work. Results identified a Clostridium perfringens Type A and E. coli bacteria. The sows had been vaccinated prefarrowing with a commercial vaccine for E. coli and Clostridium perfringens Type C. Because of the unavailability of a commercial Clostridium perfringens Type A vaccine, an autogenous formulation was prepared for the Type A. This was given in addition to the farm's normal prefarrowing vaccinations. In addition, BMD (Alpharma) was added to lactation feed at 250g./ton to help prevent Clostridium perfringens Type A.

Case Study No. 2 I was called to a 2,400-sow farm experiencing a sudden increase in piglet diarrhea in the farrowing barn.

Preweaning death loss had been under 10%, and sows were being vaccinated for E. coli and Clostridium perfringens Type C. The diarrhea had recently increased across all parities, affecting about 30% of litters. Breeding performance was excellent, and the farrowing crates were being pushed to make room for additional litters. In many of the farrowing rooms, they weren't able to use all- in, all-out (AIAO) pig flow.

Affected pigs were sent to a diagnostic lab for aerobic and anaerobic bacterial isolation, histopathology and virus work-up. E. coli and Clostridium perfringens Type A were isolated.

Management changes made to address the immediate diarrhea problems included: * All piglets were placed on ceftiofur within day 2 of birth.

* BMD at 250g./ton was placed in the lactating feed.

* AIAO was tried in farrowing, crates were cleaned and allowed to dry prior to entry of a new group.