An animal with endoparasites is said to be _____ and an animal with ectoparasites is said to be _____.

An animal that has endoparasites, such as worms or protozoans, is described as infected because these parasites reside within the host's body. The term "infected" implies that these parasites are causing some form of disease or disruption to the normal functioning of the animal's body. Conversely, when an animal has ectoparasites, such as fleas or ticks, it is referred to as infested. Ectoparasites live on the exterior of the host, thus leading to the term "infested" to indicate that the animal is burdened by these external parasites.

This distinction is important in veterinary pharmacology as it helps in understanding the nature of the parasitic problem and the types of treatments that may be necessary. Typically, treatments will differ between infections caused by endoparasites and infestations caused by ectoparasites, making it vital for veterinary professionals to use the correct terminology when assessing and treating these conditions.