Effects of subclinical inflammation on C-reactive protein and haptoglobin levels as well as specific humoral immunity in dogs vaccinated against canine distemper and parvovirus

Background: The aim of the present study was to assess the effects of subclinical inflammation on specific humoral immunity in dogs vaccinated with Nobivac (R) DHP based on serum levels of CRP and Hp. Dogs from the group I were administered Nobivac (R) DHP, the vaccine against distemper, infectious hepatitis and parvovirus whereas group II animals received subcutaneous turpentine oil to induce subclinical inflammation, followed by Nobivac (R) DHP after 24 h. Animals in group III received only turpentine oil in the way and amount identical to that as in group II. Results: Nobivac DHP relatively poorly induced the immune inflammatory response showing good immunogenic properties, which was evidenced by only a double increase in mean CRP and Hp levels associated with antigenic stimulation in group I. In group II, serum neutralization (SN) and haemagglutination inhibition (HI) results were quite closely correlated with serum levels of CPR and Hp. Conclusions: Our findings suggest that the efficacy of vaccinations in dogs can be significantly affected by subclinical inflammations, which is indicated by a correlation between serum CRP and Hp levels versus antibody titres for canine distemper and parvovirus in both experimental groups of dogs (group I and II). The correlation of mean CRP and Hp values in dogs with subclinical inflammation and after vaccination with the kinetics of increasing antibody titres against distemper and parvovirus in group II dogs reflects the severity of inflammatory response and the extent of specific humoral immunity. Routine determinations of serum CRP and Hp levels as the indices of inflammation severity can be the essential biochemical markers for assessment of dogs' health in the period preceding specific immunoprophylaxis and efficacy of the vaccine.