| Strongylida | |
|---|---|
 | |
| Nippostrongylus brasiliensis | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Nematoda |
| Class: | Chromadorea |
| Order: | Rhabditida |
| Suborder: | Strongylida |
| Superfamilies | |
The Strongylida suborder includes many of the important nematodes found in the gastrointestinal tracts of ruminants, horses, and swine, as well as the lungworms of ruminants and the hookworms of dogs and cats. [1]
This suborder includes (superfamily - included families):
These are parasites of the digestive tracts of terrestrial snakes and, rarely, lizards. About 33 species are known in one family (Diaphanocephalidae), two genera (Diaphanocephalus and Kalicephalus) and six subgenera. Snakes can be orally infected with third-stage larvae experimentally, but it is a mystery how snakes become infected in the wild. Since snakes flick their tongue around to examine their environment, it is possible that the nematodes attach to the tongue. Kalicephalus species lack host specificity, and are intolerant of each other - different species space themselves apart in the host's gut. [2]
The hookworms, these have very large buccal cavities. They infect the small intestine of mammals. Many hookworms can infect the host by skin penetration, an important discovery made by A. Looss when he accidentally spilt larvae in water on his hand in 1898. The larvae release enzymes to assist their passage through the skin. There are three species that infect humans. Fourth-stage and adult hookworms suck blood, which can cause anaemia in humans with malnutrition. The third-stage larvae are carried by general circulation to the heart and lungs. In the lungs, they enter alveoli and begin to develop to the fourth stage. Then they migrate to the trachea and intestine. They attach to the wall of the intestine, reaching the adult stage in two to seven weeks, depending on the species. If the infective third stage is ingested orally, the worm can still, nevertheless, attach to the gut wall and develop to the adult stage. In a resistant host, the third stage larva can invade tissue and persist, eventually infecting offspring in females either in milk or prenatally. This phenomenon, well-studied in trichostrongyles of herbivores and known as arrest, occurs in several hookworm species such as Ancylostoma caninum in canids, Uncinaria lucasi in fur seals and Ancylostoma duodenale in humans. [2]
These have large buccal capsules and leaf-like structures known as corona radiata. Most of them infect the large intestine by oral ingestion of the larva. The superfamily consists of the Strongylidae (including the strongyles of equines), Chabertiidae (including the nodular worms), Syngamidae (including the gapeworms of birds) and Deletrocephalidae (of Rhea americana ). The gapeworms (Syngaminae) develop to the third larval stage inside the egg. Some strongyles, including the gapeworms, use earthworms and gastropods as paratenic hosts. The final hosts of strongyles are generally herbivores, such as horses, ruminants, ratite birds and Australian marsupials. [3]
Trichostrongyloidea are divided into 14 families and 24 subfamilies. These worms have very small mouths and are found in a large number of hosts. They generally infect the stomach or intestine. Species that infect herbivorous hosts climb onto vegetation via films of moisture. Some species such as those infecting rodents can use either the oral or percutaneous route. There are unusual features in the development and transmission of some Trichostrongyloidea species. For example, Ollulanus tricuspis, which infects the stomach of pigs, is autoinfective: the sole means of transmission is through the pig vomiting. Arrested development is a well-studied feature, which may occur in temperate zones when the weather is too cold, or when it is too dry. This is known as seasonal arrest. In ewes, they wait for parturition and lactation, when there will be a population of young animals with little or no immunity; the sudden production of eggs by newly matured worms is known as spring rise. Another factor involved in stimulating arrest is overpopulation of adult worms. [4]
All of these parasites go through a snail to infect the lungs or vascular system of mammals, like artiodactyls, carnivores, marsupials, and cetacea.
Hookworm infection is an infection by a type of intestinal parasite known as a hookworm. Initially, itching and a rash may occur at the site of infection. Those only affected by a few worms may show no symptoms. Those infected by many worms may experience abdominal pain, diarrhea, weight loss, and tiredness. The mental and physical development of children may be affected. Anemia may result.
Necator americanus is a species of hookworm commonly known as the New World hookworm. Like other hookworms, it is a member of the phylum Nematoda. It is an obligatory parasitic nematode that lives in the small intestine of human hosts. Necatoriasis—a type of helminthiasis—is the term for the condition of being host to an infestation of a species of Necator. Since N. americanus and Ancylostoma duodenale are the two species of hookworms that most commonly infest humans, they are usually dealt with under the collective heading of "hookworm infection". They differ most obviously in geographical distribution, structure of mouthparts, and relative size.
Ancylostoma duodenale is a species of the roundworm genus Ancylostoma. It is a parasitic nematode worm and commonly known as the Old World hookworm. It lives in the small intestine of hosts such as humans, cats and dogs, where it is able to mate and mature. Ancylostoma duodenale and Necator americanus are the two human hookworm species that are normally discussed together as the cause of hookworm infection. They are dioecious. Ancylostoma duodenale is abundant throughout the world, including Southern Europe, North Africa, India, China, southeast Asia, some areas in the United States, the Caribbean, and South America.
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.
A gapeworm, also known as a red worm and forked worm, is a parasitic nematode worm that infects the tracheas of certain birds. The resulting disease, known as "gape", occurs when the worms clog and obstruct the airway. The worms are also known as "red worms" or "forked worms" due to their red color and the permanent procreative conjunction of males and females. Gapeworms are common in young, domesticated chickens and turkeys.
Strongylus vulgaris, commonly known as the blood worm, is a common horse parasite in the phylum Nematoda. It looks like a long worm with a large biting mouth. They are usually reddish in color because of all the blood they take from the equine host. This nematode is considered to be one of the "most pathogenic" of the large strongyles subphylum and is distributed worldwide, wherever there are grassland and temperate environments.
Ancylostomiasis is a hookworm disease caused by infection with Ancylostoma hookworms. The name is derived from Greek ancylos αγκύλος "crooked, bent" and stoma στόμα "mouth".
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.
Toxocara canis is a worldwide-distributed helminth parasite that primarily infects dogs and other canids, but can also infect other animals including humans. The name is derived from the Greek word "toxon," meaning bow or quiver, and the Latin word "caro," meaning flesh. T. canis live in the small intestine of the definitive host. This parasite is very common in puppies and somewhat less common in adult dogs. In adult dogs, infection is usually asymptomatic but may be characterized by diarrhea. By contrast, untreated infection with Toxocara canis can be fatal in puppies, causing diarrhea, vomiting, pneumonia, enlarged abdomen, flatulence, poor growth rate, and other complications.
Trichostrongylus tenuis, also known as the strongyle worm, is a gut nematode found in the United Kingdom, sensitive to Pyrantel pamoate. Larvae have a short migration inside the mucosa of the intestine and return quickly to the digestive tract.
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.
Oesophagostomum is a genus of parasitic nematodes (roundworms) of the family Strongylidae. These worms occur in Africa, Brazil, China, Indonesia and the Philippines. The majority of human infection with Oesophagostomum is localized to northern Togo and Ghana. Because the eggs may be indistinguishable from those of the hookworms, the species causing human helminthomas are rarely identified with accuracy. Oesophagostomum, especially O. bifurcum, are common parasites of livestock and animals like goats, pigs and non-human primates, although it seems that humans are increasingly becoming favorable hosts as well. The disease they cause, oesophagostomiasis, is known for the nodule formation it causes in the intestines of its infected hosts, which can lead to more serious problems such as dysentery. Although the routes of human infection have yet to be elucidated sufficiently, it is believed that transmission occurs through oral-fecal means, with infected humans unknowingly ingesting soil containing the infectious filariform larvae.
Ancylostoma braziliense is a species of hookworm belonging to the genus Ancylostoma. It is an intestinal parasite of domestic cats and dogs. Severe infection is often fatal to these pets, especially in puppies and kittens. The infection is particularly endemic in the southern United States. It is most often confused with the zoonotic hookworm species Ancylostoma ceylanicum because of their uncanny resemblance.
Ancylostoma caninum is a species of nematode known as a hookworm, which principally infects the small intestine of dogs. The result of A. caninum infection ranges from asymptomatic cases to death of the dog; better nourishment, increasing age, prior A. caninum exposure, or vaccination are all linked to improved survival. Other hosts include carnivores such as wolves, foxes, and cats, with a small number of cases having been reported in humans.
The Ancylostomatidae are a family of worms that includes the hookworms.
Trichostrongylus species are nematodes, which are ubiquitous among herbivores worldwide, including cattle, sheep, donkeys, goats, deer, and rabbits. At least 10 Trichostrongylus species have been associated with human infections. Infections occur via ingestion of infective larvae from contaminated vegetables or water. Epidemiological studies indicate a worldwide distribution of Trichostrongylus infections in humans, with the highest prevalence rates observed in individuals from regions with poor sanitary conditions, in rural areas, or who are farmers / herders. Human infections are most prevalent in the Middle East and Asia, with a worldwide estimated prevalence of 5.5 million people.
Ostertagia ostertagi, commonly known as the medium stomach worm or brown stomach worm, is a parasitic nematode of cattle. O. ostertagi can also be found to a lesser extent in sheep, goats, wild ruminants, and horses. It causes ostertagiosis, which is potentially fatal in cattle. It is found worldwide and is economically important to cattle industries, particularly those found in temperate climates.
Hookworms are intestinal, blood-feeding, parasitic roundworms that cause types of infection known as helminthiases. Hookworm infection is found in many parts of the world, and is common in areas with poor access to adequate water, sanitation, and hygiene. In humans, infections are caused by two main species of roundworm, belonging to the genera Ancylostoma and Necator. In other animals the main parasites are species of Ancylostoma.
Strongyloides westeri, commonly referred to as intestinal threadworm, is a species of small nematode parasite in the family Strongylidae. Strongyloides are commonly found in the small intestine of mammals, that are characterized by an unusual lifecycle that involves one generations of free-living adult worms.
Cat worm infections, the infection of cats (Felidae) with parasitic worms, occur frequently. Most worm species occur worldwide in both domestic and other cats, but there are regional, species and lifestyle differences in the frequency of infestation. According to the classification of the corresponding parasites in the zoological system, infections can be divided into those caused by nematode and flatworms - in the case of the latter, mainly cestoda and trematoda - while other strains are of no veterinary significance. While threadworms usually do not require an intermediate host for their reproduction, the development cycle of flatworms always proceeds via alternate hosts.
| Authority control databases: National |
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