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Disease Information



Parasite Profiles







A parasite is a living organism which lives in another living organism, known as the host. The parasite gains an advantage from the host, usually without providing any compensation to the host.

Endoparasites live within a host and must obtain nutrients from that animal in order to survive and reproduce. The host's ability to thrive, or even survive, is often decreased as a result of the parasite's presence. Many parasites are specific to a species of animal. For example, Trichuris vulpis, the whipworm, infects only dogs and foxes, whereas another species of the same genus, Trichuris ovis, infects sheep. Other parasites, such as Ancylostoma braziliense, a hookworm, may infect several species, including dog, cat and fox. Each species of parasite has a predilection for a specific location within the host animal. .

Parasites that feed or live on the body surface of a host animal are called ectoparasites. Most of them are arthropods, that is, invertebrates with jointed legs and hard external skeletons. Arthropod ectoparasites fall into two classes, arachnids and insects.

Ectoparasite infectation affects the health of the host animal in several ways. Cats may be so preoccupied with the itching and irritation caused by ectoparasites that feeding is irregular and, consequently, the host cat may lose weight or grow slowly. Such "parasite worry" is a problem in almost all infestations. Animals may become emaciated and susceptible to various other sicknesses, such as bacterial and viral diseases. Heavy infestations can cause serious blood loss. Perhaps the most serious aspect of ectoparasite infestation is the ability of some ectoparasites to transmit other serious diseases, such as the blood parasite haemobartonella felis.

Various feline parasites are found worldwide. The incidence of parasites in cats and their importance are greatly influenced by geographic location, season of the year and climatic conditions.

The effects of both endo and ectoparasites acting together on cats are greater than the damage caused by either type of parasite by itself. For example, a cat that is heavily infested with fleas will be more severely affected by a sudden build-up in roundworm parasites than would an animal that is free of ectoparasites.

Roundworms are important internal parasites of cats. These parasites are widespread and can cause death in heavily infected kittens.

Most parasites have complex life cycle coordinated with climatic conditions. The seasonal incidence of each parasite species varies in different regions. This seasonal incidence of parasites is a very important factor to consider when planning a total parasite control program.

Parasite Groups