Investigating the Combined Use of a Multivalent Live Viral DHPPi Vaccine and an Inactivated Rabies Vaccine with a Novel Tetravalent Canine Leptospirosis Vaccine

Introduction
Recently, a novel liquid tetravalent canine leptospirosis vaccine developed in line with current independent vaccination recommendations (1) has been authorised in Europe. this new vaccine (nobivac® L4 – MSD animal Health) will commonly be used to recon- stitute the respective routine injectable lyophilized viral multicomponent vaccines, and studies to support this simultaneous use have been reported (2). in this study we have investigated the possibility of any adverse effect or serological interference in dogs administered nobivac L4, nobivac DHppi and nobivac rabies at the same time.

Materials and Methods
Twenty-one 9 week old Spf dogs were divided into three equal groups. Group 1 was vaccinated with DHppi reconstituted with L4, group 2 with DHppi reconstituted with L4 and also a separate inoculation of rabies vaccine, group 3 with just rabies vaccine. all dogs were observed for any adverse local or systemic signs post-inoculation. Serum samples were collected post-vaccination in order to compare the antibody responses to all the components between the different groups.

Results and conclusions
No systemic reactions were observed in any of the vaccinated dogs. Some of the dogs vaccinated with all three vaccines showed small, painless local swellings at the sites of both inoculations which were considered to be minor and acceptable. the dogs in groups 1 and 2 showed similar antibody responses to the DHppi and L4 antigens and thus there was no evidence of any serological interference arising from the rabies vaccination. Like- wise the dogs in groups 2 and 3 showed a similar antibody response to the rabies compo- nent thus showing no evidence of any interference from the DHppi and L4 vaccination. it can be concluded that nobivac rabies, nobivac DHppi and nobivac L4 all appear to be well tolerated and serologically compatible when administered at the same time.