Parasites: Most canine parasites are worms (hookworms, round worms, tapeworms, heartworms), and can be taken care of by your vet. General symptoms include lethargy, diarrhea, and small worms or egg fragments in the feces, though specific parasites have different symptoms. Mites, fleas and ticks count among external parasites. Even indoor Cavalier King Charles Spaniels (dogs) can catch parasites via mosquitoes, or brief periods they spend outdoors or with other dogs.
