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Definition of Toxicology
2008-01-30 17:00:00
Toxicology is the study of the harmful effects of chemical compounds on biologic systems, including their properties, actions, and effects. The toxic agent is referred to as a toxicant or poison. The term toxin refers to poisons produced by a biologic source (eg, venoms, plant toxins); the redundant term biotoxin is occasionally used. Toxicosis, poisoning, and intoxication are synonymous terms for the disease produced by a toxicant. Toxicity (sometimes incorrectly used instead of poisoning) refers to the amount of a toxicant necessary to produce a detrimental effect. Hazard describes the likelihood of poisoning under conditions of use.If 2 poisons act via similar mechanisms on the same organs, their combined effects may be additive. Synergism is the amplification of the combined actions of 2 or more agents having the same biologic effects. Antagonism is the inhibition or elimination of the effect of one agent by another; it may be chemical or functional.Toxicant accumulation and bio...
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Spider Bites
2008-01-30 16:59:00
Envenomation of animals by spiders is relatively uncommon and difficult to recognize. It may be suspected on clinical signs, but confirmatory evidence is rare. Spider s of medical importance in the USA do not inflict particularly painful bites, so it is unusual for a spider bite to be suspected until clinical signs appear. It is also unlikely that the offending spider will remain in close proximity to the victim for the time (30 min to 6 hr) required for signs to develop. Almost all spiders are venomous, but few possess the attributes necessary to cause clinical envenomation in mammals?mouth parts of sufficient size to allow penetration of the skin and toxin of sufficient quantity or potency to result in morbidity.The spiders in the USA that are capable of causing clinical envenomation belong to 2 groups?widow spiders ( Latrodectus spp ) and brown spiders (mostly Loxosceles spp ).Widow Spiders:Widow spiders usually bite only when accidental skin contact occurs. The most common specie...

Mercury Poisoning
2008-01-30 16:57:00
Mercury exists in a variety of organic and inorganic forms. The replacement of commercial mercurial compounds, including antiseptics (eg, mercurochrome), diuretics, and fungicides by other agents has decreased the likelihood of mercurial toxicosis; however, the possibility of exposure to environmental sources of organic methylmercury exists.Inorganic Mercurials:These include the volatile elemental form of mercury (used in thermometers) and the salted forms (mercuric chloride [sublimate] and mercurous chloride [calomel]). Ingested inorganic mercury is poorly absorbed and low in toxicity. Large amounts of these mercurials are corrosive and may produce vomiting, diarrhea, and colic. Renal damage also occurs, with polydipsia and anuria in severe cases. In rare cases of chronic inorganic mercurial poisoning, the CNS effects resemble those of organic mercury poisoning. Mercury vapor from elemental mercury produces corrosive bronchitis and interstitial pneumonia and, if not fatal, may lead...
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Blogsvertise
2008-01-30 03:16:00
Blogsvertise is a blogging service website that allows you to earn money from writing an entry in your own blog within the entry that must include 2-3 links to the advertiser?s website URL in their blog. You don?t need to have necessary endorse the advertiser's website products or services, just need to mention them in your blog. Even you can post it relate to your own life, review the site, compliment or even complain about it, it is entirely up to bloggers decision.Signing up as a publisher with Blogsvertise requires you to have a blog for about 30 days old with good quality content. You have to utilize space on your blog. You'll get various assignments for which you'll be paid. Payment essentially varies and will depend on the quality, traffic and many more factors. So, what are you waiting for, sign up here and make money easily?

Giant Kidney Worm Infection in Mink and Dogs
2008-01-24 03:36:00
Mink are the most common definitive host for Dioctophyma renale , the largest known nematode, which has a worldwide distribution. Many other species, including dogs and humans, can become infected. The definitive host contracts the parasite by ingesting encysted larvae in raw fish (eg, pike, bullhead) or frogs, or by ingesting an infected annelid worm. The larvae penetrate the bowel wall and migrate first to the liver and later to the kidneys. In dogs, the parasite often fails to reach the kidneys and may be found free in the abdominal cavity. Kidney worms grow larger in dogs than in mink, reaching up to 103 cm. Female worms are larger than male worms, and both are blood red. Both male and female worms must be present in the same kidney to complete the life cycle. Barrel-shaped, yellow-brown eggs with a thick pitted shell measuring 71-84 × 45-52 µm are shed into the urine.In the kidneys, the worm(s) cause obstruction, hydronephrosis, and destruction of the renal parenchyma. The rig...
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Transmission, Epidemiology, and Pathogenesis of Foot and Mouth Disease
2008-01-24 03:34:00
Transmission of FMD is generally by contact between susceptible and infected animals. Infected animals have a large amount of aerosolized virus in their exhaled air, which can infect other animals via the respiratory or oral routes. All excretions and secretions from the infected animal contain virus, and virus may be present in milk and semen for up to 4 days before clinical signs appear. Aerosolized FMD virus can spread a considerable distance as a plume, depending on weather conditions, particularly when the relative humidity is >60% and when the topography of the surface over which it is dispersing does not cause turbulence. FMD has been transmitted to calves via infected milk, and milk tankers carrying infected milk have been implicated in the spread of disease between farms. Fodder can become contaminated after contact with infected animals and iatrogenic spread of FMD has been reported. Although horses, dogs, and cats are not affected by FMD, they can act as mechanical vector...
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Definition of Foot and Mouth Disease (FMD)
2008-01-24 03:32:00
Foot-and-mouth disease (FMD) is a highly infectious viral disease of cattle, pigs, sheep, goats, buffalo, and artiodactyl wildlife species. It is characterized by fever and vesicles in the mouth and on the muzzle, teats, and feet. In a susceptible population, morbidity approaches 100%. The disease is rarely fatal except in young animals. All species of deer and antelope, elephant, and giraffe are susceptible to FMD, but Old World camels are resistant to natural infection. South American camelids such as alpacas and llamas, although susceptible, are probably of no epidemiologic significance. Rats, mice, and guinea pigs can be infected experimentally.FMD is endemic in the Middle East, Iran, the southern countries of the former Soviet Union, India, and southeast Asia. Sporadic outbreaks occurred in South Korea in 2000 and 2002, Japan in 2000, and in peninsular Malaysia. FMD is restricted to Luzon island in the Philippines. Australasia and Indonesia are free of FMD, as are Central and N...
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Definition of Swine Vesicular Disease
2008-01-24 03:29:00
Swine vesicular disease (SVD) is typically a transient disease of pigs in which vesicular lesions appear on the feet and snout and in the mouth. It does not cause severe production losses, and recent outbreaks of infection have been mainly subclinical. However, infection is of major economic importance because it must be differentiated from foot-and-mouth disease, eradication is costly, and embargoes on export of pigs and pork products are often imposed on nations not free of SVD.Although infection in laboratory workers has occurred, and the virus may be present in sheep or cattle, pigs are said to be the only natural host. The disease was first identified in Italy in 1966 and subsequently in Hong Kong, Japan, Taiwan, and 16 countries in Europe. Although SVD virus was eradicated from Japan in the mid-1970s and most European countries by the mid-1980s, it has remained endemic in Italy and caused sporadic outbreaks of disease in other European countries during the 1990s and in Portuga...
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What is Aspiration Pneumonia?
2008-01-24 03:25:00
Aspiration pneumonia is a pulmonary infection characterized by inflammation and necrosis caused by inhalation of foreign material. The severity of the inflammatory response depends on the material aspirated, the type of bacteria aspirated, and the distribution of aspirated material in the lungs.Faulty administration of medicines is a common cause of aspiration pneumonia. Liquids administered by drench or dose syringe should not be given faster than the animal can swallow. Drenching is particularly dangerous when the animal?s tongue is drawn out, when the head is held high, or when the animal is coughing or bellowing. Administration of liquids by nasal intubation is not without risk, and careful technique is especially necessary in debilitated animals.Inhalation of irritant gases or smoke is an infrequent cause. Aspiration of vomitus or attempts by animals to eat or drink while partially choked can result in aspiration pneumonia as well. Disturbances of deglutition, as in anesthetize...
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Abnormal ingestive behavior on Dogs
2008-01-24 03:13:00
Abnormal ingestive behavior has the following necessary condition: consistent ingestion of abnormal amounts or types of food or nonfood material in a manner or frequency not consistent with previous behavior. The following condition is sufficient: incessant consumption of food or nonfood material, or incessant avoidance of food, in a manner that interferes with normal social functioning. Abnormal ingestive behavior includes pica (consistent ingestion of nonfood material), coprophagia (ingestion of feces that is neither accidental nor incidental), polyphagia, aerophagia, psychogenic water drinking (consumption of water in excess of that necessary to meet daily fluid balance needs or to thermoregulate or lubricate food for ingestion), anorexia, and gorging. Except for pica and aerophagia?which truly seem different from ingestion or lack of ingestion involving food?it is very difficult, although not impossible, to rule out all physiologic causal associations. It is logical that abnorma...
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Fluid Therapy of Equine Emergency Medicine
2008-01-24 02:51:00
Injuries with blood loss, exhaustion, acute rhabdomyolysis, and overheating are conditions that require emergency fluid replacement. Fluids can be administered for maintenance purposes, when fluid intake is physically not possible, or for replacement purposes when excessive losses have been incurred or ongoing losses are anticipated.In athletic horses, replacement therapy is the mainstay of fluid therapy. Designing a replacement fluid therapy regimen requires consideration of the volume and type of fluids required as well as the route and rate of administration. The volume of fluid to give on a daily basis can be calculated using the following: volume to administer (L) = maintenance (60 mL/kg/day) + immediate losses (body wt [kg] ¥ estimate of dehydration) + ongoing losses. Ongoing losses can be difficult to determine. Maintenance volumes are ~1L/hr for adult horses. Dehydration can be estimated by using clinical and laboratory parameters.Ongoing losses can be difficult to estimate,...
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First Aid and Transport of Emergency Medicine
2008-01-24 02:38:00
Owners can provide significant medical assistance at the scene of the injury. At the time of the initial telephone call, the owner should be questioned about the level of consciousness, breathing pattern, and perfusion of the animal. The first concern is for the safety of the owner. Placing a light cloak or cloth over the head of the animal can lessen external stimuli that may cause fearful and aggressive reactions. Cats can be placed in dark boxes to minimize stress during transport; the box should have holes large enough so that the cat can be observed.When moving the animal, motion of the head, neck, and spine should be minimized. A flat, firm board of wood, cardboard, or thick fabric can be used to provide support. Radiographs can also be taken through these materials without having to move the animal.Mouth-to-nose resuscitation and chest compressions may provide enough respiratory and circulatory support to maintain life during transport. If the animal is unconscious and not br...
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Emergency Medicine Definition
2008-01-24 02:31:00
Emergency patients present special challenges because underlying problems may not be evident for 24-48 hr after initial presentation. Problems can arise from an acute illness, from a chronic illness that has decompensated, or from an unexpected complication of another illness. All postoperative patients are considered critical care patients until life-threatening anesthetic or surgical complications are ruled out. The golden rule of emergency medicine is to treat the most life-threatening problems first.Variables that contribute to the overall success of emergency treatment include the severity of the primary illness or injury, the amount of fluid or blood lost, age of the animal, previous health problems, the number and extent of associated conditions, time delay in instituting therapy, the volume and rate of fluid administration, and the choice of fluids (eg, crystalloid, blood components, or synthetic colloids). Therapy must be done at the right time, in the right amount, and in ...
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PATELLA LUXATION IN DOGS
2007-09-19 10:19:00
IntroductionPatella luxation is probably one of the most common canine orthopedicconditions seen in veterinary practices in New Zealand. Most patellaluxations are medial and the condition is also seen in cats. Although thecondition is predominantly seen in miniature and toy breeds of dogs it isnot uncommon in larger breeds. Left untreated patella luxation can lead topain, lameness, degenerative joint disease, and cranial cruciate ligamentinjury. A firm understanding of the anatomy and pathogenesis of patellaluxation is required before recommending treatment options to owners ofaffected dogs.AnatomyThe patella is a large sesamoid bone that acts as a lever to decrease theamount of force needed to extend the stifle joint. The patella is maintainedin place by the medial and lateral trochlear ridges, the stifle joint capsule,the parapatellar fibrocartilages and fascia, and the femoropatellar ligaments.The femoropatellar ligaments are thin bands of tissue bilaterally that connectthe patel...
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ORAL NEOPLASIA
2007-09-19 10:18:00
The most common canine oral tumours are fibrosarcoma (FSA),osteosarcoma (OSA), squamous cell carcinoma (SCC), malignant melanoma(MM) and epulides. The most common seen in cats are FSA and SCC. Withthe exception of some epulides, all of these tumours are locally invasiveand often involve adjacent bone, but rarely metastasise. For this reason,incomplete tumour resection often results in recurrence. The goal of surgicaltreatment is to attain tumour-free margins because it has been shown thishas a significant positive influence on survival: One study showed dogs inwhich tumour cells extended to the periphery of the excised margin (dirtymargins) were 3.6 times more likely to die from the tumour compared withdogs where the margins were tumour free (clean margins).The goal of surgical treatment is to attain tumour-free marginsThe surgical techniques of maxillectomy and mandibulectomy offer wideexcision of oral tumours including the underlying bone. Function andcosmetic results are good and...
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Heatstroke or Hyperthermia
2007-08-27 02:42:00
Heatstroke occurs when normal body mechanisms cannot keep the body's temperature in a safe range. Animals do not have efficient cooling systems (like humans who sweat) and get overheated easily. A dog with moderate heatstroke (body temperature from 104º to 106ºF) can recover within an hour if given prompt first aid and veterinary care (normal body temperature is 100-102.5°F). Severe heatstroke (body temperature over 106ºF) can be deadly and immediate veterinary assistance is needed.You should remove the dog from the hot area immediately. Prior to taking him to your veterinarian, lower his temperature by wetting him thoroughly with cool water (for very small dogs, use lukewarm water), then increase air movement around him with a fan. CAUTION: Using very cold water can actually be counterproductive. Cooling too quickly and especially allowing his body temperature to become too low can cause other life-threatening medical conditions. The rectal temperature should be checked every 5 mi...
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What is Euthanasia?
2007-08-23 20:05:00
Euthanasia is defined as an easy, painless death. In regard to animals, euthanasia is the act of killing an animal in a humane manner. The primary objectives of animal euthanasia are: 1) relieving pain and suffering of the animal(s) to be euthanized, 2) minimizing the pain, anxiety, distress, and fear the animal experiences before consciousness is lost, and 3) inducing a painless and distress-free death.Observing the behavioral and physiologic responses of animals is beneficial in assessing whether the objectives of euthanasia are being met. A variety of behaviors and physiologic responses may be demonstrated by animals experiencing pain and/or fear, including (but not limited to) distress vocalizations, struggling, escape attempts, agitation, freezing, aggression, fearful postures or facial expressions, trembling, salivating, urinating, defecating, evacuation of anal sacs, pupillary dilation, panting, tachycardia, and sweating. Response to euthanasia procedures (handling, restraint...
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Euthanasia for Clients and Veterinarians
2007-08-23 20:03:00
As in any intimate relationship, when an animal companion dies or is ill, people are likely to feel stress, sorrow, and grief. This may include the animal?s family and neighbors in the community, as well as the veterinary team that has provided care. The significance of pets dying and the consequent emotional impact on clients is now clearly profiled within the veterinary profession, with educational materials and support groups, hotlines, and counseling available. The relatively short lifespan of dogs and cats means that clients face losing several animals during a lifetime. Most veterinarians themselves have painful memories of losing a particular animal and understand only too well the pain their clients feel.An extra burden comes in assuming responsibility for the moment of death by euthanasia. The philosophical dilemma is the same as that posed by human euthanasia. One must weigh the value of mercy or the Golden Rule to relieve pain and suffering with the wrongness of killing o...
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What is Animal Welfare?
2007-08-23 20:02:00
Reducing or preventing the incidence of animal pain or distress and promoting animal well-being (and even pleasure) are overall goals of animal welfare. These goals pertain to animals on farms or in laboratories as well as companion animals. Aversive handling, even if infrequent, has stressful consequences for pigs and other farm animals, with resulting adverse effects on reproduction and development. Aversive handling has similar effects on animals in other settings. Veterinarians are often the first contacts when someone seeks help for animals being badly treated or receiving inadequate care.Intentional, deliberate abuse of animals is an extreme marker of a likely pattern of abuse elsewhere within a family. Veterinarians who report suspected animal abuse sometimes can avert similar abuse of other vulnerable family members, especially children or the elderly. Two studies reported that >90% of veterinarians would report cases of suspected animal abuse to authorities. A majority agre...
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Health Benefits of Pets for Human
2007-08-23 19:59:00
The companionship of pets relaxes and entertains people. In coming to know their clients, veterinarians can assess the importance of the pet to a family and the extent to which the family members benefit from the potential psychosocial effects of living with an animal. During stressful periods in people?s lives, many studies have reported that pets offer meaningful comfort that is protective against depression and loneliness. Elderly women living alone score more favorably on measures of mental health; even college-aged women report less loneliness if living with companion animals rather than alone. Similar comforting effects of animal companions, whether cats or dogs, in warding off depression were reported for patients with Alzheimer?s disease who had a companion animal and were cared for at home and for men with AIDS whose social lives were shrinking. Elderly people experiencing typical life stresses are less affected (as measured by number of medical visits) when they have a com...
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Veterinary Family Practice
2007-08-23 19:56:00
The primacy of pets in clients? lives today resembles their importance in the lives of veterinarians who entered the profession due to their involvement with animals. Clients become deeply attached to and care about the health and well-being of their companions. Their expectations for veterinary care are becoming more similar to that ideally provided in human medicine?clients anticipate superb care for both the animal and themselves. As high-tech medicine expands within veterinary specialties, a more sophisticated level of family support is required and expected by many clients. The current elevated importance of animals, often regarded as part of the family, revolutionizes the nature of veterinary practice to include the entire family. Because veterinarians now deal with the family plus the animal, and no longer just treat the animal, the style and emphasis of companion animal practices have shifted, as reflected in the terms ?veterinary family practice? or ?bond-centered practice....
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Human-Animal Bond
2007-08-23 19:55:00
Companion animals are now considered to be family members, no longer the outdoor dogs and cats on farms that were typical for many families a few decades ago. The human-animal bond has become a household term, reflecting the entry of dogs, cats, and other pets into our everyday lives. Cats are sharply increasing in popularity and numbers, including households with multiple cats, leading to the emergence of veterinary practices serving only cats. Yet a strong majority of Americans (73%) feel that dogs rather than cats are the better pet, as reported in a 2001 Gallup Poll. A 2002 AVMA study of household pets reported that dogs received 1.9 veterinary visits per animal in 2001, as compared with 1.0 visits per cat. Dogs had a total of 117 million veterinary visits, contrasting with 71 million for cats, but revealing the economic significance of both.In addition to the growing awareness of the human-animal bond, the roles of animals have expanded into new applications. At the same time, ...
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Feeding and Management Practices of the chicken
2007-08-21 19:03:00
Success of the feeding program should be measured by how it achieves the breeder?s goals for proper weight and development specific to each strain. Feed and the length of time required for attaining certain weights in pullets and turkeys are presented in the growth and feed tables which can be used as a guide in estimating the amount of feed required. These figures may vary considerably due to differences in the nutrient density of feed, strain or breed of bird, amount of feed wasted, and environmental temperature.Most diets used in feeding poultry are nutritionally ?complete? diets that are commercially mixed, ie, prepared by feed manufacturing companies, most of which employ trained nutritionists. The formulation and mixing of poultry feeds requires knowledge and experience in purchasing ingredients, experimental testing of formulas, laboratory control of ingredient quality, and computer applications. Improper mixing can result in vitamin and mineral deficiencies, lack of protecti...
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Nutritional Requirements of the Chicken
2007-08-21 18:58:00
Poultry continue to rank high in their ability to convert feed into food products. Such high efficiency has increased progressively in recent decades. The nutrient requirement figures published in Nutrient Requirements of Poultry (National Academy of Sciences, 1994) are the most recent available and should be viewed as minimal nutrient needs for poultry. They are derived from experimentally determined levels after an extensive review of the published data. Criteria used to determine the adequacy of a given nutrient include growth, feed efficiency, health, productivity, and quality of poultry product. These requirements do not, however, include a margin of safety. Consequently, under practical conditions in which there may be different strains, energy content of the diets, environmental temperatures, type of floor, availability of nutrients from various feedstuffs, destruction or loss of nutrients in the gut, pro-oxidants, intestinal parasites, mycotoxins, diseases, and many other st...
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Newcastle Disease (Avian pneumoencephalitis)
2007-08-21 18:53:00
Newcastle disease is an acute viral disease of domestic poultry and many other bird species. It is a worldwide problem that presents primarily as a respiratory disease, but depression, nervous manifestations, or diarrhea may be the predominant clinical form. Mortality is variable. Occurrence of a virulent form of the disease is reportable and may result in trade restrictions.Etiology and Pathogenesis:Newcastle disease is caused by an RNA virus, Newcastle disease virus (NDV), synonymous with avian paramyxovirus-1 which is in the genus Avulavirus , family Paramyxoviridae. Isolates are classified into 1 of 3 virulence groups by chicken embryo and chicken inoculation as virulent (velogenic), moderately virulent (mesogenic), or of low virulence (lentogenic). Lentogenic strains are used widely as live vaccines in healthy chickens. Clinical manifestations vary from high morbidity and mortality to asymptomatic infections. The severity of an infection is dependent on virus virulence and the ...
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Chicken Anemia Virus Infection
2007-08-21 18:49:00
Chicken anemia virus (CAV), a 25 nm, nonenveloped, icosahedral virus with a single-stranded, circular DNA genome, is the only member of the genus Gyrovirus of the Circoviridae family. The genome codes for 3 viral proteins (VP). VP1 is the capsid protein, but VP2 may be needed as a scaffold protein to allow proper folding of VP1. VP3, or apoptin, is a nonstructural protein that induces apoptosis in infected cells. CAV infects only chickens, although antibodies have been detected in Japanese quail. The virus is present worldwide based on serology and virus isolation. The disease, chicken infectious anemia, has been described in most countries where chickens are raised commercially.Horizontal transmission of CAV is by the fecal-oral route and perhaps by the respiratory route. Vertical transmission occurs when seronegative hens become infected and continues until neutralizing antibodies develop. Chicks hatched from these eggs are viremic, and CAV can rapidly spread horizontally from the...
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Behavioral Medicine
2007-08-13 02:13:00
An animal?s ?behavior? is the product of its genetic composition, the environment in which the animal functions, and the animal?s experience (ie, what it has learned given its previous genetic × environment interaction). While this section focuses primarily on abnormal behavior of domestic animals, the extent to which an animal?s behavior is abnormal is defined by its deviation from ?normal.? For each group of domestic animals, normal social and group behavior is outlined and followed by a listing of the common behavioral disorders and treatment approaches.In behavioral medicine, diagnoses are not diseases; correlation is not causality. Behavioral conditions for which there is putative etiologic and pathophysiologic heterogeneity (multifactorial disorders) are complex.Phenotypic (functional, phenomenologic) diagnoses are open to various mechanistic bases of all subsequent levels. Some of these more reductionistic levels can be tested using treatment (eg, specific pharmacologic agent...
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Blood Groups Definition
2007-08-13 02:09:00
Blood groups are determined by genetically controlled, polymorphic, antigenic components of the RBC membrane. The allelic products of a particular genetic locus are classified as a blood group system. Some of these systems are highly complex with many alleles defined at a locus; others consist of a single defined antigen. Blood group systems, in general, are independent of each other, and their inheritance conforms to Mendelian dominance. For polymorphic blood group systems, an animal usually inherits 1 allele from each parent and thus expresses no more than 2 blood group antigens of a system. An exception is in cattle, in which multiple alleles or ?phenogroups? are inherited. Normally, an individual does not have antibodies against any of the antigens present on its own RBC or against other blood group antigens of that species? systems unless they have been induced by transfusion, pregnancy, or immunization. In some species (human, sheep, cow, pig, horse, cat, and dog), so-called ?...
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Blood Groups and Blood Transfusions
2007-08-13 02:05:00
Blood groups are determined by genetically controlled, polymorphic, antigenic components of the RBC membrane. The allelic products of a particular genetic locus are classified as a blood group system. Some of these systems are highly complex with many alleles defined at a locus; others consist of a single defined antigen. Blood group systems, in general, are independent of each other, and their inheritance conforms to Mendelian dominance. For polymorphic blood group systems, an animal usually inherits 1 allele from each parent and thus expresses no more than 2 blood group antigens of a system. An exception is in cattle, in which multiple alleles or ?phenogroups? are inherited. Normally, an individual does not have antibodies against any of the antigens present on its own RBC or against other blood group antigens of that species? systems unless they have been induced by transfusion, pregnancy, or immunization. In some species (human, sheep, cow, pig, horse, cat, and dog), so-called ?...
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Neurohypophysis
2007-08-03 05:48:00
The neurohypophysis (pars nervosa, posterior lobe) has 3 anatomic subdivisions. Secretion granules that contain the neurohypophyseal hormones, ie, antidiuretic hormone (ADH, vasopressin) and oxytocin, are synthesized in the hypothalamus but are released into the bloodstream in the pars nervosa. The infundibular stalk joins the pars nervosa to the overlying hypothalamus.ADH, an octapeptide synthesized in the hypothalamus, is packaged into membrane-limited granules with a corresponding binding protein (neurophysin) and transported to the pars nervosa, where it is released into the circulation. ADH binds to specific receptors in the distal part of the nephron and collecting duct of the kidney; it increases the renal tubular reabsorption of water from the glomerular filtrate.The output of ADH is directly related to the degree of hydration of the body. Hydration of the body inhibits release of ADH, while dehydration or injection of hypertonic electrolyte solutions favors release of ADH, ...