Even a small number of heartworms can be serious. Signs of heartworm include respiratory stress (difficulty breathing or rapid shallow breathing), gagging or vomiting, lethargy, loss of appetite, and weight loss.

Worms in the stool can indicate any number of worm infections ranging from hookworm to tapeworm. The parasitic hookworm is around a half-inch-long while a tapeworm can reach up to a staggering three feet long if left untreated.

Symptoms of worms in cats are pretty much the same as dog worm symptoms. Some are visible to the naked eye while others are not. One of the most obvious symptoms of worms in cats is the presence of worms in your cat’s stool. Your cat might have any number of parasitic worms in its feces such as the half-inch-long hookworm or a tapeworm. The tapeworm can reach up to a whopping three feet long if left untreated and it may have as many as 90 segments.