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Scrapie
Scrapie () is a fatal, degenerative disease affecting the nervous systems of sheep and goats. It is one of several transmissible spongiform encephalopathies (TSEs), and as such it is thought to be caused by a prion. Scrapie has been known since at least 1732 and does not appear to be transmissible to humans. However, it has been found to be experimentally transmissible to humanised transgenic mice and non-human primates. The name scrapie is derived from one of the clinical signs of the condition, wherein affected animals will compulsively scrape off their fleeces against rocks, trees or fences. The disease apparently causes an itching sensation in the animals. Other clinical signs include excessive lip smacking, altered gaits and convulsive collapse. Scrapie is infectious and transmissible among conspecifics, so one of the most common ways to contain it (since it is incurable) is to quarantine and kill those affected. However, scrapie tends to persist in flocks and can also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transmissible Spongiform Encephalopathies
Transmissible spongiform encephalopathies (TSEs), also known as prion diseases, are a group of progressive, incurable, and fatal conditions that are associated with the prion hypothesis and affect the brain and nervous system of many animals, including humans, cattle, and sheep. According to the most widespread hypothesis, they are transmitted by prions, though some other data suggest an involvement of a ''Spiroplasma'' infection. Mental and physical abilities deteriorate and many tiny holes appear in the Cerebral cortex, cortex causing it to appear like a sponge when brain tissue obtained at autopsy is examined under a microscope. The disorders cause impairment of brain function which may result in memory loss, personality changes, and Ataxia, abnormal or impaired movement which worsen over time. TSEs of humans include Creutzfeldt–Jakob disease, Gerstmann–Sträussler–Scheinker syndrome, fatal familial insomnia, and Kuru (disease), kuru, as well as the recently discovered v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prion
A prion () is a Proteinopathy, misfolded protein that induces misfolding in normal variants of the same protein, leading to cellular death. Prions are responsible for prion diseases, known as transmissible spongiform encephalopathy (TSEs), which are fatal and transmissible neurodegenerative diseases affecting both humans and animals. These proteins can misfold sporadically, due to genetic mutations, or by exposure to an already misfolded protein, leading to an abnormal Protein tertiary structure, three-dimensional structure that can propagate misfolding in other proteins. The term ''prion'' comes from "proteinaceous infectious particle". Unlike other infectious agents such as viruses, bacteria, and fungi, prions do not contain nucleic acids (DNA or RNA). Prions are mainly twisted Protein isoform, isoforms of the major prion protein (PrP), a naturally occurring protein with an uncertain function. They are the hypothesized cause of various transmissible spongiform encephalopath ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sheep
Sheep (: sheep) or domestic sheep (''Ovis aries'') are a domesticated, ruminant mammal typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus '' Ovis'', in everyday usage it almost always refers to domesticated sheep. Like all ruminants, sheep are members of the order Artiodactyla, the even-toed ungulates. Numbering a little over one billion, domestic sheep are also the most numerous species of sheep. An adult female is referred to as a ''ewe'' ( ), an intact male as a ''ram'', occasionally a ''tup'', a castrated male as a ''wether'', and a young sheep as a ''lamb''. Sheep are most likely descended from the wild mouflon of Europe and Asia, with Iran being a geographic envelope of the domestication center. One of the earliest animals to be domesticated for agricultural purposes, sheep are raised for fleeces, meat ( lamb, hogget or mutton), and milk. A sheep's wool is the most widely used animal fiber, and is usually harvested by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Small Intestine
The small intestine or small bowel is an organ (anatomy), organ in the human gastrointestinal tract, gastrointestinal tract where most of the #Absorption, absorption of nutrients from food takes place. It lies between the stomach and large intestine, and receives bile and pancreatic juice through the pancreatic duct to aid in digestion. The small intestine is about long and folds many times to fit in the abdomen. Although it is longer than the large intestine, it is called the small intestine because it is narrower in diameter. The small intestine has three distinct regions – the duodenum, jejunum, and ileum. The duodenum, the shortest, is where preparation for absorption through small finger-like protrusions called intestinal villus, intestinal villi begins. The jejunum is specialized for the absorption through its lining by enterocytes: small nutrient particles which have been previously digested by enzymes in the duodenum. The main function of the ileum is to absorb vitami ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meat And Bone Meal
Meat and bone meal (MBM) is a product of the rendering industry. It is typically about 48–52% protein, 33–35% ash, 8–12% fat, and 4–7% water. It is primarily used in the formulation of animal feed to improve the amino acid profile of the feed. Feeding of MBM to cattle is thought to have been responsible for the spread of BSE (mad cow disease); therefore, in most parts of the world, MBM is no longer allowed in feed for ruminant animals. However, it is still used to feed monogastric animals. MBM is widely used in the United States as a low-cost animal protein in dog food and cat food. In Europe, some MBM is used as ingredients in pet food, but the majority is now used as a fossil-fuel replacement for energy generation, as a fuel in cement kilns, landfilling or incineration. History In the UK, after the 1987 discovery that BSE could cause vCJD, the original feed ban was introduced in 1988 to prevent ruminant protein being fed to ruminants. In addition, it has been ill ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specified Risk Material
Specified risk material (SRM) is any of various tissues of ruminant animals that cannot be inspected and passed for human food because scientists have determined that bovine spongiform encephalopathy ( BSE)-causing prions concentrate there, representing a biological food safety hazard to consumers. The term was referred to in the United Kingdom's Specified Risk Material Order 1997 ( S.I. 1997/2964), in the United States Department of Agriculture's, and in the Canadian Food Inspection Agency's regulatory response to the first confirmed U.S. BSE case in December 2003.CRS Report for Congress: Agriculture: A Glossary of Terms, Programs, and Laws, 2005 Edition - Order Code 97-905 BSE The BSE infective agent has been foun ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peyer's Patches
Peyer's patches or aggregated lymphoid nodules are organized lymphoid follicles, named after the 17th-century Swiss anatomist Johann Conrad Peyer. * Reprinted as: * Peyer referred to Peyer's patches as ''plexus'' or ''agmina glandularum'' (clusters of glands). From (Peyer, 1681), p. 7: ''"Tenui a perfectiorum animalium Intestina accuratius perlustranti, crebra hinc inde, variis intervallis, corpusculorum glandulosorum Agmina sive Plexus se produnt, diversae Magnitudinis atque Figurae."'' (I knew from careful study of more advanced animals, the intestines bear — often here and there, at various intervals — clusters of glandular small bodies or "plexuses" of diverse size and shape.) From p. 15: ''"(has Plexus seu agmina Glandularum voco)"'' (I call them "plexuses" or clusters of glands) He described their appearance. From p. 8: ''"Horum vero Plexuum facies modo in orbem concinnata; modo in Ovi aut Olivae oblongam, aliamve angulosam ac magis anomalam disposita figuram cern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ELISA
The enzyme-linked immunosorbent assay (ELISA) (, ) is a commonly used analytical biochemistry assay, first described by Eva Engvall and Peter Perlmann in 1971. The assay is a solid-phase type of enzyme immunoassay (EIA) to detect the presence of a ligand (commonly an amino acid) in a liquid sample using antibodies directed against the ligand to be measured. ELISA has been used as a medical diagnosis, diagnostic tool in medicine, plant pathology, and biotechnology, as well as a quality control check in various industries. In the most simple form of an ELISA, antigens from the sample to be tested are attached to a surface. Then, a matching antibody is applied over the surface so it can bind the antigen. This antibody is linked to an enzyme, and then any unbound antibodies are removed. In the final step, a substance containing the enzyme's Enzyme substrate, substrate is added. If there was binding, the subsequent reaction produces a detectable signal, most commonly a color change. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasympathetic Nervous System
The parasympathetic nervous system (PSNS) is one of the three divisions of the autonomic nervous system, the others being the sympathetic nervous system and the enteric nervous system. The autonomic nervous system is responsible for regulating the body's unconscious actions. The parasympathetic system is responsible for stimulation of "rest-and-digest" or "feed-and-breed" activities that occur when the body is at rest, especially after eating, including sexual arousal, salivation, lacrimation (tears), urination, digestion, and defecation. Its action is described as being complementary to that of the sympathetic nervous system, which is responsible for stimulating activities associated with the fight-or-flight response. Nerve fibres of the parasympathetic nervous system arise from the central nervous system. Specific nerves include several cranial nerves, specifically the oculomotor nerve, facial nerve, glossopharyngeal nerve, and vagus nerve. Three spinal nerves ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pruritus
An itch (also known as pruritus) is a sensation that causes a strong desire or reflex to scratch. Itches have resisted many attempts to be classified as any one type of sensory experience. Itches have many similarities to pain, and while both are unpleasant sensory experiences, their behavioral response patterns are different. Pain creates a withdrawal reflex, whereas itches leads to a scratch reflex. Unmyelinated nerve fibers for itches and pain both originate in the skin. Information for them is conveyed centrally in two distinct systems that both use the same nerve bundle and spinothalamic tract. Classification Most commonly, an itch is felt in one place. If it is felt all over the body, then it is called ''generalized itch'' or ''generalized pruritus''. Generalized itch is infrequently a symptom of a serious underlying condition, such as cholestatic liver disease. If the sensation of itching persists for six weeks or longer, then it is called ''chronic itch'' or ''ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
