The causes of diarrhea in piglets include all three classes of pathogens: bacteria, viruses and protozoa. However, when presented with diarrhea in pigs less than 7 days of age, the list becomes much shorter: Escherichia coli, the clostridial diseases, transmissible gastroenteritis (TGE) and now porcine epidemic diarrhea (PED) virus.
Clostridium difficile is one of the clostridial diseases we see in neonatal piglet diarrhea cases. It is a common intestinal organism in many species, including pigs and people.
Clostridium difficile is an opportunistic organism that waits for a chance to proliferate and overpopulate the gut. In people, the bacterial pathogen is commonly related to antibiotic associated diarrhea (AAD). The process of giving people broad-spectrum antibiotics can reduce the number of “good” bacteria in the intestinal tract. With the good bacteria outnumbered, bacteria like Clostridium difficile can explode in numbers. This overpopulation is harmful, because the bacteria release toxins that damage the inner lining of the intestinal tract.
The classic lesion these toxins produce is edema of the tissue that binds the large colon together. This damage leads to a period of diarrhea and poor nursing by the piglet.
During this time, the piglets that are affected fall behind their littermates, leading to uneven litters at weaning.
The percentage of pigs that is affected in a production unit is quite variable, but the mortality is relatively low, usually an additional 2%-4%.
Culturing the organism from piglets with typical lesions and testing for toxins are the diagnostic tools used to confirm a diagnosis. Clostridium difficile is commonly isolated in mixed infections with other causes of diarrhea.
Generally, the clostridial organisms produce spores. The spores are very hardy in the environment, and can survive in dirt and swine facilities for long periods of time.
Controlling this pathogen requires a multifaceted approach. Addressing the environment, the sow’s colostral immunity, and piglet treatments are necessary for a good control program. Physically washing away the spores with a hot-water, high-pressure sprayer is the best approach to improving the environment. Excellent sanitation is important for control, as spores resist disinfection and drying.
But options exist if the concern still persists. Drying agents that assist in keeping the piglet’s sleeping area dry can help limit the exposure and transfer of spores from piglet to piglet.
Normal antibiotics that are used for the control of E.coli diarrhea do not control Clostridium difficile well. Antibiotics such as tylosin and the tetracyclines have been used with some success in the treatment of individual piglets.
Since infection generally occurs prior to Day 7 of the pig’s life, there is not enough time for the piglet to develop immunity. Thus, colostral immunity from the sow is important for control.
There are no commercial Clostridium difficile vaccines, so production units will need to work with their veterinarian to isolate the organism from the farm and produce an autogenous vaccine.
We were called to a 3,000-sow, farrow-to-wean operation with a history of diarrhea cases. Preweaning mortality increased from an average of 11% to 15% due to an increase in diarrhea. Difference in piglet size at weaning was a concern. The number of small piglets at weaning had increased from 4% to 15%.
Postmortem examinations were performed on a number of pigs. Culture and sensitivity tests were done on submitted tissues. Both Clostridium perfringens Type A and Clostridium difficile were isolated from multiple pigs.
Sanitation procedures were reviewed with the staff. Piglets showing diarrhea were treated with tylosin injections starting shortly after birth. The injections reduced the incidence of diarrhea and brought the mortality back down to pre-infection levels.
Both the Clostridium perfringens Type A and Clostridium difficile isolates were submitted for the production of an autogenous vaccine. These new isolates were added to the farm’s current E. coli vaccine. The new autogenous vaccine was given to sows at five weeks and two weeks before farrowing. The colostral protection from the new vaccine controlled the diarrhea. The antibiotic injections were discontinued without incident.
Clostridial diseases are very difficult to totally remove from the environment, due to the stable spores they produce. Thorough washing with a hot-water pressure washer is the best approach to limiting exposure to piglets.
Treatment of affected piglets with antibiotics can be helpful. But prevention of the disease through sow vaccination and the colostrum she provides appears to be the most complete approach at this time.
Contact your veterinarian to develop a program that is right for your farm.