Why are my Yorkies sick after their rabies vaccine?

I took my 2 Yorkies to have their annual rabies vaccines yesterday afternoon. They were fine all evening but they are both very sluggish and not themselves this morning. Has anyone else ever experienced this with their dog? If so, how long did it last and what should I do for them? Also, does anyone know the side effects of a rabies vaccine in dogs?

Dogs can have adverse reactions to any vaccines.

There is good evidence that the first rabies vaccine at a young age is effective to produce enough antibodies, and the second rabies vaccine within a year is then sufficient to provide lifelong protection. Further annual or even 3 year rabies vaccinations are therefore not needed, although they may be required by law.

Rabies vaccines are usually NOT adjusted for the dog's body weight.

Please consider reducing the frequency of the rabies vaccine to the minimum required by law. DEFINITELY consider 3 year rabies vaccine instead of annually, if the 3 year is allowed by your local laws.