I have a question about the beginning.

Okay at the very beginning we see the two bad guys coming in with a dog and Doctor Varnick somes out and he tells them that he needs puppies. After that we see the other dogs being used in tests like the on dog with the electordes on his head. I have been wondering about this for years but why did the vet want puppies? I was told it was probably for a certain experiment that needed puppies.