|
Saprolegniales
Saprolegniales is an order of water mould. Members of the order are responsible for numerous parasitic infections affecting aquatic life, such as crayfish plague and ulcerative dermal necrosis. References Oomycete orders {{watermould-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oomycete
The Oomycetes (), or Oomycota, form a distinct phylogenetic lineage of fungus-like eukaryotic microorganisms within the Stramenopiles. They are filamentous and heterotrophic, and can reproduce both sexually and asexually. Sexual reproduction of an oospore is the result of contact between hyphae of male antheridia and female oogonia; these spores can overwinter and are known as resting spores. Asexual reproduction involves the formation of chlamydospores and sporangia, producing motile zoospores. Oomycetes occupy both saprophytic and pathogenic lifestyles, and include some of the most notorious pathogens of plants, causing devastating diseases such as late blight of potato and sudden oak death. One oomycete, the mycoparasite '' Pythium oligandrum'', is used for biocontrol, attacking plant pathogenic fungi. The oomycetes are also often referred to as water molds (or water moulds), although the water-preferring nature which led to that name is not true of most species, whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saprolegniales
Saprolegniales is an order of water mould. Members of the order are responsible for numerous parasitic infections affecting aquatic life, such as crayfish plague and ulcerative dermal necrosis. References Oomycete orders {{watermould-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saprolegnia
''Saprolegnia'' is a genus of water moulds often called cotton moulds because of the characteristic white or grey fibrous patches they form. Current taxonomy puts ''Saprolegnia'' as a genus of the heterokonts in the order Saprolegniales. Habits ''Saprolegnia'', like most oomycetes, is both a saprotroph and necrotroph. Typically feeding on waste from fish or other dead cells, they will also take advantage of creatures that have been injured. An infection is known as oomycosis. ''Saprolegnia'' is tolerant to a wide range of temperature, , but is more prevalent in lower temperatures. While it is found most frequently in freshwater, it will also tolerate brackish water and even moist soil. ''Saprolegnia'' filaments (hyphae) are long with rounded ends, containing the zoospores. Saprolegnia generally travels in colonies consisting of one or more species. They first form a mass of individual hyphae. When the mass of hyphae grows large enough in size to be seen without use of a micr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saprolegniaceae
Saprolegniaceae is a Family (biology), family of water mould, freshwater mould. James Ellis Humphrey (1861-1897), an American mycologist did significant work on this family. Taxonomy Saprolegniaceae contains the following genera, species, and subspecies. * ''Achlya'' ** ''Achlya ambisexualis'' ** ''Achlya americana'' ** ''Achlya androgyna'' ** ''Achlya apiculata'' ** ''Achlya aquatica'' ** ''Achlya bisexualis'' ** ''Achlya bonariensis'' ** ''Achlya caroliniana'' ** ''Achlya catenulata'' ** ''Achlya colorata'' ** ''Achlya conspicua'' ** ''Achlya crenulata'' ** ''Achlya debaryana'' ** ''Achlya dubia'' ** ''Achlya flagellata'' ** ''Achlya glomerata'' ** ''Achlya heterosexualis'' ** ''Achlya hypogyna'' ** ''Achlya intricata'' ** ''Achlya klebsiana'' ** ''Achlya oblongata'' ** ''Achlya oligacantha'' ** ''Achlya orion'' ** ''Achlya ornata'' ** ''Achlya oviparvula'' ** ''Achlya papillosa'' ** ''Achlya primoachlya'' ** ''Achlya prolifera'' ** ''Achlya prolife ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crayfish Plague
Crayfish plague (''Aphanomyces astaci'') is a water mold that infects crayfish, most notably the European ''Astacus'' which dies within a few weeks of being infected. When experimentally tested, species from Australia, New Guinea and Japan were also found to be susceptible to the infection. Morphology Crayfish plague invades tissue with hyphae. The hyphae develop sporangia that release amoeboid primary spores, which develop into flagellated secondary zoospores after encystment. The secondary zoospores have two flagella each and can repeatedly encyst before finally reaching a host, attaching and germinating. History Crayfish plague first arrived in Europe in Italy in 1859, either with imported crayfish from North America, or in ballast water discharge. After its original introduction in Italy in 1860, it spread quickly through Europe and was discovered in Sweden in 1907, in Spain in 1972, in Norway in 1971, in Great Britain in 1981, in Turkey in 1984 and in Ireland in 1987. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sesame
Sesame (; ''Sesamum indicum'') is a plant in the genus '' Sesamum'', also called benne. Numerous wild relatives occur in Africa and a smaller number in India. It is widely naturalized in tropical regions around the world and is cultivated for its edible seeds, which grow in pods. World production in 2018 was , with Sudan, Myanmar, and India as the largest producers. Sesame seed is one of the oldest oilseed crops known, domesticated well over 3,000 years ago. ''Sesamum'' has many other species, most being wild and native to sub-Saharan Africa. ''S. indicum,'' the cultivated type, originated in India. It tolerates drought conditions well, growing where other crops fail. Sesame has one of the highest oil contents of any seed. With a rich, nutty flavor, it is a common ingredient in cuisines around the world. Like other foods, it can trigger allergic reactions in some people and is one of the nine most common allergens outlined by the Food and Drug Administration. Etymology Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Order (biology)
Order () is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. An immediately higher rank, superorder, is sometimes added directly above order, with suborder directly beneath order. An order can also be defined as a group of related families. What does and does not belong to each order is determined by a taxonomist, as is whether a particular order should be recognized at all. Often there is no exact agreement, with different taxonomists each taking a different position. There are no hard rules that a taxonomist needs to follow in describing or recognizing an order. Some taxa are accepted almost universally, while others are recognized only rarely. The name of an order is usually written with a capital letter. For some groups of organisms, their orders may follow consist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Ulcerative Dermal Necrosis
Ulcerative dermal necrosis (UDN) is a chronic dermatological disease of cold water salmonid fish that had a severe impact on north Atlantic Salmon and sea trout stocks in the late 1960s and 1970s–1980. Despite much investigation, the cause of UDN has not been determined. The onset of symptoms occurs after migration into freshwater. Affected fish develop severe skin lesions which begin on the head and back, and near the tail. Lesions become infected with overgrowths of oomycetes, such as ''Saprolegnia'', giving the affected areas a slimy blue-grey appearance. The most severely affected fish frequently die before spawn Spawn or spawning may refer to: * Spawning, the eggs and sperm of aquatic animals Arts, entertainment and media * Spawn (character), a fictional character in the comic series of the same name and in the associated franchise ** ''Spawn: Armageddon' ...ing. Although the worst effects of the disease were seen in the 1970s and 1980, even now large numbers of salmon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
