Serological Response of Puppies to the Selected Canine Vaccines and Vaccination Schedules against Canine Distemper Virus

This study was undertaken to compare the serological response of dogs to four commercially available combination vaccines and three different vaccination schedules to canine distemper virus (CDV). A total of 120 healthy puppies (20 puppies per group) at 6 weeks of age were randomly assigned to one of four vaccines [C, G, K, and V (or V3) groups] and one of vaccination schedules [V2 and V4 groups]. At six, nine, and 12 weeks of age, puppies in each group were vaccinated with one of four combination vaccines subcutaneously. And puppies in V2 and V4 groups were vaccinated with V vaccine every 2 weeks and 4 weeks, respectively. The serological responses to CDV component of the vaccines were determined by measuring SN titers. The immunogenicity of V vaccine was superior to the other vaccines and optimum vaccination schedule was 3 times vaccination with 3 weeks-interval starting vaccination at 6 weeks of age. Although puppies were vaccinated at 6 weeks of age, the geometric mean CDV titers of puppies in all groups by 9 weeks of age were under the protective level. Therefore, prophylactic measures should include isolation of young dogs from the dog population until vaccination can be expected to provide protection.