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Fish Diseases And Parasites
Like humans and other animals, fish suffer from diseases and parasites. Fish defences against disease are specific and non-specific. Non-specific defences include skin and scales, as well as the mucus layer secreted by the epidermis that traps microorganisms and inhibits their growth. If pathogens breach these defences, fish can develop inflammatory responses that increase the flow of blood to infected areas and deliver white blood cells that attempt to destroy the pathogens. Specific defences are specialised responses to particular pathogens recognised by the fish's body, that is adaptative immune responses. In recent years, vaccines have become widely used in aquaculture and ornamental fish, for example vaccines for commercial food fishes like Aeromonas salmonicida, furunculosis in salmon and Lactococcosis\Streptococcosis in farmed grey mullet, Tilapia and koi herpes virus in koi. Some commercially important fish diseases are VHS, ICH, and whirling disease. Parasites ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gizzard Shad
''Dorosoma'' is a genus that contains five species of shads, within the herring family Clupeidae. The five species are native to the North and/or Central America, and are known from both fresh water and the waters of estuaries and bays. The American gizzard shad is important to the food web in America due to being a source of game fish food. They also have a long history of stock introductions that can lead to disruptions to the food web. Species * '' Dorosoma anale'' Meek, 1904 (Mexican river gizzard shad) * ''Dorosoma cepedianum The American gizzard shad (''Dorosoma cepedianum''), also known as the mud shad, is a member of the herring family of fish, and is native to large swaths of fresh and brackish waters of the United States of America. The adult has a deep body, w ...'' ( Lesueur, 1818) (American gizzard shad) * '' Dorosoma chavesi'' Meek, 1907 (Nicaragua gizzard shad) * '' Dorosoma petenense'' ( Günther, 1867) (threadfin shad) * '' Dorosoma smithi'' C. L. Hub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Koi Herpes Virus
''Cyprinid herpesvirus 3'' (also CyHV-3, koi herpes virus or KHV) is a species of virus causing a viral disease that is very contagious to the common carp ''Cyprinus carpio''. Pathology It is most commonly found in ornamental koi, which are often used in outdoor ponds or as feeder stock. The first case of KHV was reported in 1998, but not confirmed until later in 1999. KHV is a DNA-based virus. After discovery, it was identified as a strain of herpesvirus. Like other strains, KHV stays with the infected fish for the duration of their lives, making the recovered and exposed fish potential carriers of the virus. Koi fish infected with KHV may die within the first 24–48 hours of exposure. The virus is found in 33 countries. KHV is listed as a nonexotic disease of the EU, so is watched closely by the European Community Reference Laboratory for Fish Diseases. Symptoms of KHV include: * Gill mottling * Red and white patches appearing on gills * Bleeding gills * Sunken eyes * P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasite
Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has characterised parasites as "predators that eat prey in units of less than one". Parasites include single-celled protozoans such as the agents of malaria, sleeping sickness, and amoebic dysentery; animals such as hookworms, lice, mosquitoes, and vampire bats; fungi such as honey fungus and the agents of ringworm; and plants such as mistletoe, dodder, and the broomrapes. There are six major parasitic strategies of exploitation of animal hosts, namely parasitic castration, directly transmitted parasitism (by contact), trophicallytransmitted parasitism (by being eaten), vector-transmitted parasitism, parasitoidism, and micropredation. One major axis of classification concerns invasiveness: an endoparasite lives inside the host's body ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siamese Fighting Fish
The Siamese fighting fish (''Betta splendens''), commonly known as the betta, is a freshwater fish native to Southeast Asia, namely Cambodia, Laos, Myanmar, Malaysia, Indonesia, Thailand, and Vietnam. It is one of 73 species of the genus '' Betta,'' but the only one eponymously called "betta", owing to its global popularity as a pet; ''Betta splendens'' are among the most popular aquarium fish in the world, due to their diverse and colorful morphology and relatively low maintenance. Siamese fighting fish are endemic to the central plain of Thailand, where they were first domesticated at least 1,000 years ago, among the longest of any fish. They were initially bred for aggression and subject to gambling matches akin to cockfighting. Bettas became known outside Thailand through King Rama III (1788-1851), who is said to have given some to Theodore Cantor, a Danish physician, zoologist, and botanist. They first appeared in the West in the late 19th century, and within decades be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Merck Veterinary Manual
The ''Merck Veterinary Manual'' is a reference manual of animal health care. It was first published by Merck & Co., Inc. in 1955. It contains concise, thorough information on the diagnosis and treatment of disease in a wide variety of species. The ''Manual'' is available as a book, published on a non-profit basis. Additionally, the full text can be accessed for free via the website, or downloaded in its entirety via an app. In January 2020, the website was redesigned with a more helpful search function without advertising. Interactive features on the website include quizzes, case studies, and clinical calculators. In addition, there are animal health news summaries and commentaries. History The ''Merck Veterinary Manual'' was first published in 1955. It was based on the ''Merck Manual of Diagnosis and Therapy'', which was first published in 1899 as a reference for physicians. The first edition of the ''Veterinary Manual'' included contributions from over 200 authors, with 389 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Velvet Disease
Velvet disease (also called gold-dust, rust and coral disease) is a fish disease caused by dinoflagellate parasites of the genera '' Amyloodinium'' in marine fish, and '' Oodinium'' in freshwater fish. The disease gives infected organisms a dusty, brownish-gold color. The disease occurs most commonly in tropical fish, and to a lesser extent, marine aquaria. Life cycle The single-celled parasite's life cycle can be divided into three major phases. First, as a tomont, the parasite rests at the water's floor and divides into as many as 256 tomites. Second, these juvenile, motile tomites swim about in search of a fish host, meanwhile using photosynthesis to grow, and to fuel their search. Finally, the adolescent tomite finds and enters the slime coat of a host fish, dissolving and consuming the host's cells, and needing only three days to reach full maturity before detaching to become a tomont once more. Pathology Velvet (in an aquarium environment) is usually spread by contaminat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasitic
Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has characterised parasites as "predators that eat prey in units of less than one". Parasites include single-celled protozoans such as the agents of malaria, sleeping sickness, and amoebic dysentery; animals such as hookworms, lice, mosquitoes, and vampire bats; fungi such as honey fungus and the agents of ringworm; and plants such as mistletoe, dodder, and the broomrapes. There are six major parasitic strategies of exploitation of animal hosts, namely parasitic castration, directly transmitted parasitism (by contact), trophicallytransmitted parasitism (by being eaten), vector-transmitted parasitism, parasitoidism, and micropredation. One major axis of classification concerns invasiveness: an endoparasite lives inside the host's b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oodinium
''Oodinium'' is a genus of parasitic dinoflagellates. Their hosts are salt- and fresh-water fish, causing a type of fish velvet disease (also called gold dust disease). One species has also been recorded on various cnidarians. The host typically develops a yellow or gold "dust" scattered on its head, fins and body. At this stage, the infestation is already severe. The attack usually starts at the gills, at which stage it is difficult to observe. The host fish is irritated, and often sporadically darts about or rubs itself against rocks. The yellowish spots are more vivid under a strong light source. It is very similar to '' Ichthyophthirius'', though the oodinium spots are yellowish and smaller. The life cycle of oodinium starts as a dinospore that swims in the water to look for a suitable host. As it attaches itself onto the host skin, it forms a hard shell protecting itself against the outside environment while it is eating the fish skin cells. This is the cyst stage seen a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copeia
''Ichthyology & Herpetology'' (formerly ''Copeia'') is a quarterly peer-reviewed scientific journal covering research in ichthyology and herpetology that was originally named after Edward Drinker Cope, a prominent American researcher in these fields. It is the official journal of the American Society of Ichthyologists and Herpetologists. According to the ''Journal Citation Reports'', ''Copeia'' has a 2021 impact factor of 1.857, ranking it 65th out of 176 journals in the category "Zoology". History On December 27, 1913, John Treadwell Nichols published the first issue of ''Copeia''. This issue consisted of a single piece of paper folded to form four pages of information with five articles. The cover of the pamphlet bore the inscription: "Published by the contributors to advance the science of coldblooded vertebrates." In 2020, the American Society of Ichthyologists and Herpetologists voted to rename the journal, Ichthyology & Herpetology. Name change The journal was n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Gill
Fish gills are organs that allow fish to breathe underwater. Most fish exchange gases like oxygen and carbon dioxide using gills that are protected under gill covers (operculum) on both sides of the pharynx (throat). Gills are tissues that are like short threads, protein structures called filaments. These filaments have many functions including the transfer of ions and water, as well as the exchange of oxygen, carbon dioxide, acids and ammonia. Each filament contains a capillary network that provides a large surface area for exchanging oxygen and carbon dioxide. Fish exchange gases by pulling oxygen-rich water through their mouths and pumping it over their gills. Within the gill filaments, capillary blood flows in the opposite direction to the water, causing counter-current exchange. The gills push the oxygen-poor water out through openings in the sides of the pharynx. Some fish, like sharks and lampreys, possess multiple gill openings. However, bony fish have a single gill op ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crustacean
Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods emerged deep in the Crustacean group, with the completed group referred to as Pancrustacea. Some crustaceans ( Remipedia, Cephalocarida, Branchiopoda) are more closely related to insects and the other hexapods than they are to certain other crustaceans. The 67,000 described species range in size from '' Stygotantulus stocki'' at , to the Japanese spider crab with a leg span of up to and a mass of . Like other arthropods, crustaceans have an exoskeleton, which they moult to grow. They are distinguished from other groups of arthropods, such as insects, myriapods and chelicerates, by the possession of biramous (two-parted) limbs, and by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cymothoa Exigua
''Cymothoa exigua'', or the tongue-eating louse, is a parasitic isopod of the family Cymothoidae. It enters fish through the gills. The female attaches to the tongue, while the male attaches to the gill arches beneath and behind the female. Females are long and wide. Males are about long and wide. The parasite severs the blood vessels in the fish's tongue, causing the tongue to fall off. It then attaches itself to the remaining stub of tongue and the parasite itself effectively serves as the fish's new "tongue". Behavior Using its front claws, ''C. exigua'' severs the blood vessels in the fish's tongue, causing the tongue to necrose from lack of blood. The parasite then replaces the fish's tongue by attaching its own body to the muscles of the tongue stub. The parasite apparently does not cause much other damage to the host fish, but Lanzing and O'Connor (1975) reported that infested fish with two or more of the parasites are usually underweight. Once ''C. exigua'' repl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
