Kansas State University researchers have developed what appears to be a promising vaccine against Porcine Circovirus Type 2 (PCV2), a disease that researchers predict every swine herd in the United States is infected with.
In a recently completed study of the vaccine, researchers found that pigs that received the vaccine showed significant reductions in mortality, increased growth rate during the finisher pig stage and fewer light weight pigs at market, said Dr. Steve Dritz, Kansas State University Research and Extension swine specialist.
K-State researchers, Bob Rowland, Dick Hesse, Steve Dritz, Jerome Nietfeld and Kyle Horlen, conducted the wean-to-finish clinical trial on a commercial hog farm in northeast Kansas using 485 pigs. The pigs were randomly divided into six groups at the time they were weaned and were given doses of the vaccine at three and six weeks of age, said Dritz. Some mortality rates prior to the trial had been as high as 20 percent.
The trial results showed that in the finisher phase, the mortality rate for vaccinated pigs was 50 percent less than for unvaccinated pigs and that the growth rate for vaccinated pigs increased by about 10 percent. Results also showed that the average market weight for vaccinated pigs was about 20 pounds heavier for the same number of days to market when compared to unvaccinated pigs.
In a separate study of the vaccine in a commercial research finishing barn, mortality, growth rate and feed efficiency improvements were calculated to result in a benefit of $3.94 per pig. Researchers are unsure however, when the vaccine will be available for use among producers.
"The next steps are to continue to evaluate the vaccine under different field conditions to ensure that it is broadly applicable across the industry," Dritz said. "We’re looking for more herds that have a less significant rise in mortality, but do have infection with the virus to see if it is still economical to vaccinate."
Research also still needs to be done to further evaluate molecular characteristics of the virus and to develop diagnostic tools, Dritz said. The diagnostic tools will aid in the investigation of how the virus spreads from herd to herd or how the infection develops into severe forms of the disease.
The researchers, who are all on faculty at K-State’s College of Veterinary Medicine, collaborated on the study with partial funding provided by the National Pork Board.
Source:
K-State Research & Extension News
http://www.oznet.ksu.edu/news/topstory.asp