The epiglottis is a leaf-shaped flap in the throat that prevents food and water from entering the trachea and the lungs. It stays open during breathing, allowing air into the larynx. During swallowing, it closes to prevent aspiration of food into the lungs, forcing the swallowed liquids or food to go along the esophagus toward the stomach instead. It is thus the valve that diverts passage to either the trachea or the esophagus.
Myiasis, also known as flystrike or fly strike, is the parasitic infestation of the body of a live animal by fly larvae (maggots) that grow inside the host while feeding on its tissue. Although flies are most commonly attracted to open wounds and urine- or feces-soaked fur, some species can create an infestation even on unbroken skin. Non-myiatic flies can be responsible for accidental myiasis.
Warble fly is a name given to the genus Hypoderma: large flies which are parasitic on cattle and deer. Other names include "heel flies", "bomb flies" and "gadflies", while their larvae are often called "cattle grubs" or "wolves." Common species of warble fly include Hypoderma bovis and Hypoderma lineatum and Hypoderma tarandi. Larvae of Hypoderma species also have been reported in horses, sheep, goats and humans. They have also been found on smaller mammals such as dogs, cats, squirrels, voles and rabbits.
Mammomonogamus is a genus of parasitic nematodes of the family Syngamidae that parasitise the respiratory tracts of cattle, sheep, goats, deer, cats, orangutans, and elephants. The nematodes can also infect humans and cause the disease called mammomonogamiasis. Several known species fall under the genus Mammomonogamus, but the most common species found to infest humans is M. laryngeus. Infection in humans is very rare, with only about 100 reported cases worldwide, and is assumed to be largely accidental. Cases have been reported from the Caribbean, China, Korea, Thailand, and Philippines.
Necatoriasis is the condition of infection by Necator hookworms, such as Necator americanus. This hookworm infection is a type of helminthiasis (infection) which is a type of neglected tropical disease.
Trichuris suis is a whipworm; the variations in thickness of the anterior and posterior segments give the parasite the characteristic "whip-like" appearance. Adult females measure 6 to 8 cm and adult males 3 to 4 cm. T. suis eggs are oval and yellow-brown with bipolar plugs. T. suis is also used in helminthic therapy studies.
Veterinary virology is the study of viruses in non-human animals. It is an important branch of veterinary medicine.
Lungworms are parasitic nematode worms of the order Strongylida that infest the lungs of vertebrates. The name is used for a variety of different groups of nematodes, some of which also have other common names; what they have in common is that they migrate to their hosts' lungs or respiratory tracts, and cause bronchitis or pneumonia. The lungworm will gradually damage the airways or lung tissue by inciting an inflammatory reaction inside the tissue. Ultimately, the parasites survive and reproduce in the respiratory tissues. The category is thus more a descriptive than a precisely taxonomic one.
Heartwater is a tick-borne rickettsial disease. The name is derived from the fact that fluid can collect around the heart or in the lungs of infected animals. It is caused by Ehrlichia ruminantium —an intracellular Gram-negative coccal bacterium. The disease is spread by various Amblyomma ticks, and has a large economic impact on cattle production in affected areas. There are four documented manifestations of the disease, these are acute, peracute, subacute, and a mild form known as heartwater fever. There are reports of zoonotic infections of humans by E. ruminantium, similar to other Ehrlichia species, such as those that cause human ehrlichiosis.
Protozoan infections are parasitic diseases caused by organisms formerly classified in the kingdom Protozoa. These organisms are now classified in the supergroups Excavata, Amoebozoa, Harosa, and Archaeplastida. They are usually contracted by either an insect vector or by contact with an infected substance or surface.
Leeches are segmented parasitic or predatory worms that comprise the subclass Hirudinea within the phylum Annelida. They are closely related to the oligochaetes, which include the earthworm, and like them have soft, muscular segmented bodies that can lengthen and contract. Both groups are hermaphrodites and have a clitellum, but leeches typically differ from the oligochaetes in having suckers at both ends and ring markings that do not correspond with their internal segmentation. The body is muscular and relatively solid; the coelom, the spacious body cavity found in other annelids, is reduced to small channels.
Chrysomya bezziana, also known as the Old World screwworm fly or screwworm, is an obligate parasite of mammals. Obligate parasitic flies require a host to complete their development. Named to honor the Italian entomologist Mario Bezzi, this fly is widely distributed in Asia, tropical Africa, India, and Papua New Guinea. The adult can be identified as metallic green or blue with a yellow face and the larvae are smooth, lacking any obvious body processes except on the last segment.
The pharynx is the part of the throat behind the mouth and nasal cavity, and above the esophagus and trachea. It is found in vertebrates and invertebrates, though its structure varies across species. The pharynx carries food to the esophagus and air to the larynx. The flap of cartilage called the epiglottis stops food from entering the larynx.
Tyrannobdella is a monotypic genus of leech, of family Praobdellidae, found in South America in the upper reaches of the Amazon. This newly found genus of leech takes sustenance from the mucous membranes of the mammalian upper respiratory tract, and is known to feed upon humans. It has eight teeth. Tyrannobdella rex was discovered feeding upon the mucous membrane of a girl who had recently bathed in the upper Amazon in Peru.
Trichomonas gallinae is a cosmopolitan parasite of birds including finches, pigeons, doves, turkeys, chickens, parrots, and raptors. The condition in birds of prey is called frounce. It is believed to be an ancient pathogen causing frounce-like symptoms in theropod dinosaurs. The same condition in pigeons is commonly called canker.
Ticks of domestic animals directly cause poor health and loss of production to their hosts. Ticks also transmit numerous kinds of viruses, bacteria, and protozoa between domestic animals. These microbes cause diseases which can be severely debilitating or fatal to domestic animals, and may also affect humans. Ticks are especially important to domestic animals in tropical and subtropical countries, where the warm climate enables many species to flourish. Also, the large populations of wild animals in warm countries provide a reservoir of ticks and infective microbes that spread to domestic animals. Farmers of livestock animals use many methods to control ticks, and related treatments are used to reduce infestation of companion animals.
Mites are small crawling animals related to ticks and spiders. Most mites are free-living and harmless. Other mites are parasitic, and those that infest livestock animals cause many diseases that are widespread, reduce production and profit for farmers, and are expensive to control.
Many species of flies of the two-winged type, Order Diptera, such as mosquitoes, horse-flies, blow-flies and warble-flies, cause direct parasitic disease to domestic animals, and transmit organisms that cause diseases. These infestations and infections cause distress to companion animals, and in livestock industry the financial costs of these diseases are high. These problems occur wherever domestic animals are reared. This article provides an overview of parasitic flies from a veterinary perspective, with emphasis on the disease-causing relationships between these flies and their host animals. The article is organized following the taxonomic hierarchy of these flies in the phylum Arthropoda, order Insecta. Families and genera of dipteran flies are emphasized rather than many individual species. Disease caused by the feeding activity of the flies is described here under parasitic disease. Disease caused by small pathogenic organisms that pass from the flies to domestic animals is described here under transmitted organisms; prominent examples are provided from the many species.
Praobdellidae is a family of hematophagous leeches which live on the mucous membranes of mammals and sometimes invertebrates. These are internal parasites that enter the body through natural orifices, and cause hirudiniases.
Limnatis nilotica is a species of leech in the family Hirudinidae. It is hematophagous, living on the mucous membranes of mammals.
