A frog's cloaca is an opening at the end of its body that performs similar functions to the reproductive and waste openings in mammals. This includes the passage of sperm, eggs and waste material. Unlike mammals, it is the only opening at the end of the frog's body.
The cloaca may become an area of concern for pet frog owners when there are nutritional deficiencies or issues with parasites. A condition known as prolapse, where a pinkish or reddish bulge emerges from the cloaca, may occur when there is not enough calcium in the frog's diet. This condition can be treated and prevented by supplementing frog food with calcium and vitamin D3.