 In their 2010 recommendations, WSAVA (World Small Animal Veterinary Association) emphasized the importance of administering "non-adjuvanted" vaccines whenever possible, as vaccines that included these immune-stimulating agents were shown to increase adverse vaccine reactions in pets.WSAVA also prefers serological testing over unnecessary boosters or re-vaccination doses of core vaccines after the initial 12-month booster that follows the puppy series of modified live virus [MLV] vaccines.This is because core vaccines show an excellent correlation between the presence of antibody and protective immunity to a disease, and have a long DOI (Duration of Immunity).