EFFICACY OF INTRADERMAL RHD VACCINATION USING VARIOUS ADJUVANTS ON FATTENING RABBITS
The purpose of this study was to assess the efficacy of various RHD vaccines
with different adjuvants when administered by intradermal route by measuring
the serological immune response and the resistance to an intramuscular
challenge with RHD virus in fattening rabbits
There is a clear necessity to protect fattening animals to prevent the losses that an outbreak of Rabbit Hemorrhagic Disease (RHD) can cause in industrial rabbit farms. Inactivated vaccines against RHD with different adjuvants are available in the market as well as several vaccination devices.
The purpose of this study was to assess the efficacy of various RHD vaccines with different adjuvants when administered by intradermal route by measuring the serological immune response and the resistance to an intramuscular challenge with RHD virus in fattening rabbits. Five batches of animals were vaccinated: Batch 1 or control rabbits were inoculated phosphate buffer solution (PBS) by intradermal route. Batches 2 and 3 were vaccinated with half-dose of oil-based Cunipravac-RHD® (Laboratorios Hipra) by subcutaneous and intradermal route respectively. Batch 4 received an experimental aluminum hydroxide-based vaccine with the same antigenic composition as Cunipravac-RHD®. Aluminum hydroxide-based Dercunimix® (Merial) was administered to Batch 5 according to manufacturer’s indications. Vaccinations did not affect health status of rabbits but produced transient local reactions at the inoculation site. Serological response at 29 days post-vaccination was not complete and varied widely between groups. In contrast, total protection after challenge was reached in Batches 2, 3 and 5. When using the intradermal route half-dose of the oil-based vaccine (Batch 3) conferred a protection comparable to a complete dose of the aluminum hydro xide-based vaccine (Batch 5) after challenge with RHD virus. Our results suggested that oil-based vaccines were more effective controlling a RHD viral infection regardless of the inoculation route used compared to the aluminum hydroxide-based vaccines based on the identification of RHD virus from vaccinated-challenged animals. (...to read more)
