In the past it has been effectively controlled by adding Carbacox, an antibiotic, to rations for finisher pigs.
Costa said antibiotics are the only defense because there is no vaccine for swine dysentery.
There have, however, been restrictions on routine use of antibiotics as feed additives and there have been restrictions on the use of some antibiotics in agriculture, all aimed at reducing the incidence of antibiotic-resistant bacteria.
A veterinarian can still prescribe antibiotics to treat the disease.
Costa said this time swine dysentery is a bit different than in the past when bloody diarrhea was the obvious symptom.
Now the symptoms can be more gradual, such as the color of feces turning green, then red, and the consistency from watery to mucoid (like the mucus in clumps of snot).
Dr. Costa is conducting research to identify the strains involved in these outbreaks and to determine if an outbreak requires the presence of more than one bacteria and, if so, which ones.
Previous trials have indicated that swine dysentery bacteria on its own will not sicken healthy pigs.
