It is almost unheard of for pet budgerigars to get worms. In the aviary, under some conditions, it is possible, and they can become infected with Ascaris roundworm. These creatures live and breed in animals’ guts, and their eggs are passed on via droppings. The adult worms can grow 3.5cm long, which in a budgie is a major problem. Once confirmed, a vet will prescribe a suitable wormer.