The first cause of PCV vaccine failure is the purchase and use of generic vaccine of low quality and titre, but the exact cause of the failures can occur in various forms.
These articles on porcine circovirus type 2 associated diseases present the most novel aspects, especially from the practical point of view, on etiology, pathogeny, epidemiology, diagnosis, treatment and prevention of the PCV2 infection.
Porcine circovirus (PCV2)
During 2012 PCV2 variants or mutants (mPCV2) appeared in the USA and were frequently associated with PCV-associated diseases. The possibility of lack of cross-protection of commercial vaccines against mPCV2 is now of major concern.
Reducing piglets mingling in farrowing and nursery facilities was found to delay the infectious process leading to a lower number of early infections. Clustering piglets by litter in small units after weaning also decreased significantly the probability of early infection.
What further increases profitability in pig production is not minimizing costs, but maximizing revenue.
Despite the evident usefulness of laboratory diagnosis, we must not forget that a field necropsy allows us to us recover part of the loss caused by the death of the animal.
PCV2 vaccination of the gilts prior to insemination with PCV2 spiked-semen showed a clear decrease of viral load in the gilts as well as a much lower viral excretion that were compatible with foetus protection.
The virus is highly resistant in the environment, showing also high resistance to chemical and thermal treatments.