New detection methods for deadly infection
ONTARIO - The Animal Health Laboratory at the University of Guelph reports on new detection methods for Swine dysentery – a cause of scouring in pigs.
11 July 2003
3 minute read
Pork producers and veterinarians have known swine dysentery – a highly contagious disease among grower and finisher pigs – by many names, including vibrionic dysentery, black scours, and bloody scours. It’s a deadly infection caused by the bacteria Brachyspira hyodysenteriae that affects the inner wall of the large intestine but doesn’t spread beyond it.
The disease can spread through a swine operation quickly. Pigs that survive may have permanent damage to the intestine, resulting in slow growth and poor performance.
Now, Drs. Hugh Cai, Gaylan Josephson, and other scientists at the Animal Health Laboratory, Laboratory Services Division, University of Guelph, can better diagnose the disease thanks to a new molecular technology called Real Time PCR (polymerase chain reaction).
“Swine diarrheas have many causes, and before we use antibiotics to treat the disease, it’s important to understand which pathogen we’re dealing with,“ says Cai. Clinical signs vary, but Cai says diarrhea always develops, with large amounts of mucous and blood in the stool. Left untreated, mortality rates are high.
Usually, researchers have only been able to test for detection of the disease after the animal’s death. Those conventional methods take several days to complete.
With the Real Time PCR method – which uses fluorescent light and magnification of up to one million times to view short stretches of the bacteria’s DNA – an examination of fecal matter allows the researcher to detect the presence of the causative agent of swine dysentery within the sample, and thus make an accurate diagnosis. And Real Time PCR takes only 30 minutes to perform.
“Once we determine the presence of the disease-causing bacteria, the herd can be treated with an antibiotic,“ says Cai. “That saves time, animals, and money.“
Source: By Paula Bialski, Ontario Pork Newsletter Ontario Pork, July 2003
