Most PCVAD affect pigs in the early finisher phase.
Finisher farms affected by PCVAD have reported one, some, or all of the following signs:
Symptoms, duration and mortality can vary by herd, group, barn or site. It is important to note, however, that within herds or groups, some PCV2-positive pigs may be asymptomatic and not express any kind of PCVAD. PCV2 is endemic worldwide and experts believe that there are no PCV2-negative swine herds. However, a herd that is positive to PCV2 will not necessarily experience PCVAD.
This form of PCVAD is usually accompanied by a variety of concurrent viral or bacterial infections. The Pork Checkoff completed a PCVAD surveillance project in 2004. It found concurrent infections with the porcine reproductive and respiratory syndrome (PRRS) virus, Mycoplasma hyopneumoniae or the swine influenza virus in 95 percent of submissions of animals presenting clinical signs and confirmed positive to the presence of PCVAD through laboratory testing. The same project also found the presence of bacteria such as Pasteurella multocida, Streptococcus suis and Salmonella sp., in PCVAD positive cases.
The presentation of PCVAD also could be related to the presence of environmental stressors. Anecdotal reports include out-of-feed events as a precursor to the presentation of the diseases. Other environmental stressors may include: