A field and an experimental study were carried out on pet and experimental stray dogs,
respectively. The objectives of these studies were to evaluate the rabies immunoprofile of dogs vaccinated with different rabies vaccines under field and experimental conditions and determine the relation between vaccine type, post vaccination intervals, health status, breed, age, gender and dewormers on rabies virus neutralizing antibody (RVNA) titer. Field study was carried out on 300 pet dogs including 1-108 months old males and females. Dogs were allocated to three groups; (I) regularly vaccinated (II) irregularly vaccinated (III) maternally immunized, each with 100 dogs bled at various stages. Experimental study was carried out on 16 adult, healthy stray dogs equally allocated to four groups; three groups for monovalent and polyvalent vaccine trials with Rabisin, Rabisyva-VP13 and Hexadog DHP-LR at day 0 and 21. Fourth group was negative control. Sample collection was carried out on day 0 and day 21 post vaccination followed by sampling at 30 days intervals till ten months, in each group. RVNA titers of the serum samples were determined by Rapid Florescent Focus Inhibition Test (RFFIT) at Rabies Lab., Kansas State University, USA. In field study 58% dogs regularly vaccinated with Rabisin, Hexadog DHP-LR and Rabisyva-VPl3 vaccines, were diagnosed with protective RV A titers while 33% dogs were suffering vaccine failure. Mean protective RVNA titers monovalent Rabisin, Rabisyva-VP13 vaccines were higher than polyvalent Hexadog DHP-LR vaccine without a significant difference. Among irregularly vaccinated dogs, only 25% dogs exhibited protective RVNA titers while 25% dogs were diagnosed with vaccine failure. 50% irregularly vaccinated dogs exhibited RVNA titer below minimum protective level. Maternal rabies immunity was minimum protective level. Maternal rabies immunity was diagnosed in 20% puppies with protective RVNA titers and 20% puppies were suffering immunity failure.
Remaining samples were either diagnosed with RVNA titers below minimum protective level or dcould not be assayed due to toxic effect on BHK cells. No relation was observed among RVNA titers and vaccine type, health status and gender in any field study group while a significant relation was observed among RVNA titers, breed, age and post immunization intervals with a significant difference in all groups.
In experimental study there was no case of vaccine failure in any group and all groups
exhibited high protective RVNA titers at the termination of study. Both the increasing and
decreasing trends were observed at various intervals of experimental study. Mean RVNA titers
Were 4.53±4.23, 3.48±3.40, 9.36±7.12 in Rabisin, Hexadog DHP-LR and Rabisyva-VP13
vaccinated groups, respectively. A relation was observed among RVNA titers, vaccines and post
vaccination time intervals with a significant difference. However health status, gender and use of imomodulatory levamisol were not found to be significantly affecting RVNA titers in any
group.
On the basis of the present study it is concluded that monovalent rabies vaccines

Rabisyva-VP13 and Rabisin generate higher RVNA titers as compared to polyvalent

Hexadog DHP-LR vaccine under the both field and experimental conditions however, a high

incidence rate of vaccine and maternal immunity failure is one of the factors that can be

responsible for high incidence of rabies especially in rabies endemic area. It is also

concluded that health status, gender and immunomodulatory effect of levamisol do not
significantly affect the rabies immunity however, there is the significant effect of age and
post immunization intervals on rabies immunity.