(Since I am suggesting we always ought to be planning our seminar presentations)
(Note 2 if we have a patron animal for ethics and canonics that leaves us needing one for physics)
On the symbolism of pigs/hogs I think there is some material which help explain the reference. We surely know it it existed from the Boscoreale cup and the Horace reference. I think there is a church father comment also referencing it in which hogs are cited as pursuing pleasure singlemindedly.
Numerous animals would work for the others but any that are known for their instinctive behavior, beavers and their dams being a great example, would fit.
For physics the first thing that comes to mind is the characteristic of curiosity. Maybe animals that construct elaborate nests or communities (beavers again maybe) could be said to be implementing physics principles, but I tend to think that the way Epicurus emphasized the study of nature more for the relief it brings from fear and perhaps even enjoyment in itself, the more characteristic trait would be curiosity. Googling "animals that represent curiosity" brings up all kinds of weird examples that are to my view too obscure if I were doing a presentation; the animal that is more universally in my experience associated with curiosity would be the cat, but no doubt there are others.