Sooner or later, most horse, dog and cat owners ask themselves the same question: Should I be deworming my animals? And if so, when and how often? And does it make sense to test faeces beforehand? Do I really have to use to use chemicals to treat worms or can natural remedies like garlic, onions or herbs help? “People are constantly asking me if deworming is really necessary,” says Ralph Rückert, a vet based in the German city of Ulm. “Deworming is the safest option for both animal and human health.” Parasites in dogs and cats can be transmitted to humans, and children in particular are at ris…