A dog's stoic disposition sometimes leaves little clue as to how he is feeling. When he gets infected by parasitic worms that live deep inside his body, the condition may go unnoticed until a dog becomes seriously ill. Subtle shifts in your dog's behavior often provide the first clues that he is under attack from the parasites.
Can't Sit Still
Parasites such as roundworms and tapeworms pass through the dog's intestinal tract and out with his feces, causing anal itching and burning. Scooter may drag his bottom across your carpet to relieve the discomfort, or spend time licking his anus and biting the hair around it. Take a peek under his tail to look for tapeworm segments or pale pink roundworms in his fur. Follow up with your vet for a test to see if he has parasites if you see worms or his obsession with his backside continues.
If your dog is constantly clearing his throat or coughing, don't automatically write it off as allergies. Heartworms and lungworms infest their namesake organs, causing blockages that make a dog cough to try to rid himself of the sensation. While a heartworm cough is known as a "soft cough" -- the dog version of throat-clearing -- lungworms often cause a hacking cough or wheezing as the dog struggles to pass air through increasingly blocked airways.
They Make Him Sick
If your dog is vomiting or has frequent diarrhea without a discernible cause, he might have parasites. Take a look at his vomit or feces to see if you can see any tapeworm segments or rice-sized, pale pink roundworms moving around. Whipworms and hookworms often cause blood to show up in the feces. A dog infected with hookworms or whipworms often has pale gums caused by anemia from blood loss.
Diary of a Couch Potato
As a dog's parasite load increases, he may just want to lie around and have less interest in going for a walk or playing a game of fetch. Despite his inactivity, he may start to grow thin and develop a rough, dull texture to his coat. He may seem sad and distracted as he stares into space with a listless look in his eyes. Have your dog checked by a vet to decide whether parasites are the cause of his inactivity.