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57-556: The term mastiff was assigned by the Europeans who first came to Tibet because that name was used to refer to nearly all large dog breeds in the West. Early Western visitors to Tibet misnamed several of its breeds, such as the Tibetan terrier , which is not a terrier , and the Tibetan spaniel , which is not a spaniel . A better name for the breed might be the Tibetan mountain dog or—to encompass

114-500: A Tibetan Mastiff lacks the unpleasant big-dog smell that affects many large breeds. The coat, whatever its length or color(s), should shed dirt and odors. Although the dogs shed somewhat throughout the year, there is generally one great molt in late winter or early spring and sometimes another, lesser molt in the late summer or early autumn. (Sterilization of the dog may dramatically affect the coat as to texture, density and shedding pattern.) Tibetan Mastiffs are shown under one standard in

171-407: A classic example of careful medical observation. Tuberculosis used to be a major cause of Addison's disease and acute adrenal failure worldwide. It remains a leading cause in developing countries today. US president John F. Kennedy (1917–1963) suffered from complications of Addison's disease throughout his life, including during his presidency, resulting in fatigue and hyperpigmentation of

228-480: A delayed but normal response is seen. Other tests may be performed to distinguish between various causes of hypoadrenalism, including renin and adrenocorticotropic hormone levels, as well as medical imaging – usually in the form of ultrasound , computed tomography or magnetic resonance imaging . Adrenoleukodystrophy , and the milder form, adrenomyeloneuropathy , cause adrenal insufficiency combined with neurological symptoms. These diseases are estimated to be

285-420: A disease process suddenly affecting adrenal function (such as adrenal hemorrhage ), or an intercurrent problem (e.g., infection, trauma) in someone known to have Addison's disease. It is a medical emergency and potentially life-threatening situation requiring immediate emergency treatment. Characteristic symptoms are: Causes of adrenal insufficiency can be categorized by the mechanism through which they cause

342-466: A dose with them at all times). Often, large amounts of intravenous fluids with the sugar dextrose are also required. With appropriate treatment, the overall outcome is generally favorable, and most people are able to lead a reasonably normal life. Without treatment, an adrenal crisis can result in death. Addison's disease affects about 9 to 14 per 100,000 people in the developed world. It occurs most frequently in middle-aged females. The disease

399-399: A dosing regimen that mimics the physiological concentrations of cortisol. Alternatively, one-quarter as much prednisolone may be used for equal glucocorticoid effect as hydrocortisone. Treatment is usually lifelong. In addition, many people require fludrocortisone as a replacement for the missing aldosterone. People with Addison's are often advised to carry information on them (e.g., in

456-473: A glucocorticoid, such as prednisone . Several follow-up blood tests are required so the dose can be adjusted until the dog is receiving the correct amount of treatment, because the medications used in the therapy of hypoadrenocorticism can cause excessive thirst and urination if not prescribed at the lowest effective dose. In anticipation of stressful situations, such as staying in a boarding kennel, dogs require an increased dose of prednisone. Lifelong treatment

513-468: A simple recessive, continued inbreeding can still produce affected puppies. Hypothyroidism is fairly common in Tibetan Mastiffs, as it is in many large "northern" breeds. They should be tested periodically throughout their lives using a complete thyroid "panel". However, because the standard thyroid levels were established using domestic dog breeds, test results must be considered in the context of what

570-495: A socialized, more domestic dog, it can thrive in a spacious, fenced yard with a canine companion, but it is not an appropriate dog for apartment living. The Western-bred dogs are generally more easy-going, although still somewhat aloof with strangers. Through hundreds of years of selective breeding for a protective flock and family guardian, the breed has been prized for being a nocturnal sentry, keeping would-be predators and intruders at bay, and barking at unidentified sounds throughout

627-422: A synthetic corticosteroid , such as hydrocortisone or fludrocortisone . These medications are typically taken orally . Lifelong, continuous steroid replacement therapy is required, with regular follow-up treatment and monitoring for other health problems which may occur. A high-salt diet may also be useful in some people. If symptoms worsen, an injection of corticosteroid is recommended (people need to carry

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684-409: A tendency for infection. As with most large breeds, some will suffer with elbow or hip dysplasia . Canine inherited demyelinative neuropathy (CIDN), an inherited condition, appeared in one of the prominent lines of Tibetan Mastiffs in the early 1980s. Unfortunately, known carriers were bred extensively and are behind many lines still being actively bred. Because the mode of inheritance appears to be as

741-423: Is "normal" for the breed, not what is normal across all breeds. Many dogs of this breed will have "low" thyroid values, but no clinical symptoms. Vets and owners differ on the relative merits of medicating dogs which test "low", but are completely asymptomatic. Originally these dogs were used to protect Buddhist monasteries and monks of Tibet from animals such as bears, wolves and snow leopards. The Tibetan Mastiff

798-690: Is 2.19 and 2.86, respectively. Death for individuals with Addison's disease often occurs due to cardiovascular disease, infectious disease, and malignant tumors, among other possibilities. The frequency rate of Addison's disease in the human population is sometimes estimated at one in 100,000. Some put the number closer to 40–144 cases per million population (1/25,000–1/7,000). Addison's can affect persons of any age, sex, or ethnicity, but it typically presents in adults between 30 and 50 years of age. Research has shown no significant predispositions based on ethnicity. About 70% of Addison's disease diagnoses occur due to autoimmune reactions, which cause damage to

855-651: Is a phenotypically distinct dog breed that was bred as a flock guardian in the high altitudes of the Himalayas and the Tibetan Plateaus . Meer Izzut-oollah (1872) wrote of the Tibetan Mastiff: The dogs of Tibet are twice the size of those seen in India, with large heads and hairy bodies. They are powerful animals...During the day they are kept chained up, and are let loose at night to guard their masters' house. In

912-411: Is a clinical emergency. An adrenal crisis can be triggered by stress, such as from an injury, surgery, or infection. Addison's disease arises when the adrenal gland does not produce sufficient amounts of the steroid hormones cortisol and (sometimes) aldosterone . It is an autoimmune disease which affects some genetically predisposed people in whom the body's own immune system has started to target

969-747: Is a large and powerful type of dog . Mastiffs are among the largest dogs, and typically have a short coat , a long low-set tail and large feet; the skull is large and bulky, the muzzle broad and short ( brachycephalic ) and the ears drooping and pendant-shaped. European and Asian records dating back 3,000 years show dogs of the mastiff type. Mastiffs have historically been guard dogs , protecting homes and property, although throughout history they have been used as hunting dogs , war dogs and for blood sports , such as fighting each other and other animals, including bulls , bears and even lions . Historical and archaeological evidence suggests that mastiffs have long been distinct in both form and function from

1026-434: Is also critical with this breed, because of their reserved nature with strangers and guardian instincts. They can be excellent family dogs, depending on the family; owners must understand canine psychology and be able and willing to spend a lot of time and devotion to training their dogs. Lack of consistency can result in the creation of unpredictable dogs. The protectiveness of Tibetan Mastiffs requires alertness and planning by

1083-514: Is also found in wild canids such as the wolf and other wild animals. Since its estrus usually takes place during late autumn, most Tibetan Mastiff puppies are born between December and January. Its double coat is long, subject to climate, and found in a wide variety of colors, including solid black, black and tan, various shades of red (from pale gold to deep red) and bluish-gray (dilute black), often with white markings. As of 2014, some breeders had begun marketing white Tibetan mastiffs. The coat of

1140-400: Is called autoimmune polyendocrine syndrome type 1 . The presence of Addison's in addition to autoimmune thyroid disease, type 1 diabetes, or both, is called autoimmune polyendocrine syndrome type 2 . An "adrenal crisis" or "Addisonian crisis" is a constellation of symptoms that indicates severe adrenal insufficiency. This may be the result of either previously undiagnosed Addison's disease,

1197-466: Is excluded. If the short test is abnormal, the long test is used to differentiate between primary adrenal insufficiency and secondary adrenocortical insufficiency. The long test uses 1 mg tetracosactide (intramuscular). Blood is taken 1, 4, 8, and 24 hours later. Normal plasma cortisol level should reach 1,000 nmol/L by 4 hours. In primary Addison's disease, the cortisol level is reduced at all stages, whereas in secondary corticoadrenal insufficiency,

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1254-1176: Is named after Thomas Addison , a graduate of the University of Edinburgh Medical School , who first described the condition in 1855. The symptoms of Addison's disease can develop over several months and resemble other medical conditions. Most common symptoms are caused by low levels of hormones that would normally be produced by the adrenal glands. Low blood cortisol can cause a variety of symptoms, including fatigue , malaise , muscle and joint pain, reduced appetite , weight loss , and increased sensitivity to cold. Gastrointestinal symptoms such as nausea, abdominal pain, and vomiting are particularly common. Low aldosterone can cause affected people to crave salty foods, as well as develop low blood pressure that leads to dizziness upon standing. In women, low dehydroepiandrosterone (DHEA) can result in dry and itchy skin, loss of armpit and pubic hair, and reduced sexual drive. Young children with Addison's disease may have insufficient weight gain and recurrent infections. Low cortisol also interferes with adrenocorticotropic hormone (ACTH) regulation, sometimes resulting in

1311-633: Is needed when severe infections, vomiting, or diarrhea occur, as these conditions can precipitate an Addisonian crisis. A person who is vomiting may require injections of hydrocortisone, instead. Those with low aldosterone levels may also benefit from a high-sodium diet. It may also be beneficial for the people with Addison's disease to increase their dietary intake of calcium and vitamin D. High dosages of corticosteroids are linked to osteoporosis so these may be necessary for bone health. Sources of calcium include dairy products, leafy greens, and fortified flours among many others. Vitamin D can be obtained through

1368-603: Is still considered somewhat uncommon, as more active breeders arose and produced adequate numbers of dogs, various registries and show organizations (FCI, AKC) began to recognize the breed. In 2008, the Tibetan Mastiff competed for the first time in the Westminster Kennel Club Dog Show . Since AKC recognition, the number of active breeders has skyrocketed, leading to over-breeding of puppies, many of which are highly inbred and of questionable quality. Initially,

1425-502: The ACTH receptor gene (or related genes, such as in the Triple-A or Allgrove syndrome). DAX-1 mutations may cluster in a syndrome with glycerol kinase deficiency with a number of other symptoms when DAX-1 is deleted together with a number of other genes. To form cortisol, the adrenal gland requires cholesterol , which is then converted biochemically into steroid hormones. Interruptions in

1482-532: The Belgian Mastiff , have the word "mastiff" in their name, but are not considered true mastiffs. Many older English sources refer to mastiffs as bandogs or bandogges, although technically the term "bandog" meant a dog that was tethered by a chain (or "bande") that would be released at night; the terms "mastiff" and "bandog" were often used interchangeably. One of the most famous "bandog" programs in England, led to

1539-656: The Great Pyrenees , Bernese Mountain Dog , Rottweiler and Saint Bernard , and that these large breed dogs are probably partially descended from the Tibetan Mastiff. In 2014, a study added the Leonberger to the list of possible relatives. The Tibetan Mastiff was able to adapt to the extreme highland conditions of the Tibetan Plateau very quickly compared with other mammals such as the yak , Tibetan antelope , snow leopard , and

1596-556: The wild boar . The Tibetan mastiff's ability to avoid hypoxia in high altitudes, due to its higher hemoglobin levels compared with low-altitude dogs, was due to prehistoric interbreeding. In 2020, a genomic analysis indicates that a ghost population of an unknown wolf-like canid which is deeply-diverged from modern Holarctic wolves and dogs has contributed the EPAS1 allele found in both Himalayan wolves and dogs, and this allows them to live in high altitudes. Mastiff A mastiff

1653-471: The "bandog" breeds. In the twentieth century the term "bandog" was revived to describe some large fighting mastiff type dogs crossed with any bulldog in the United States. Addison%27s disease Addison's disease , also known as primary adrenal insufficiency , is a rare long-term endocrine disorder characterized by inadequate production of the steroid hormones cortisol and aldosterone by

1710-511: The West, but separated by the Indian breed standard into two varieties: Lion Head (smaller; exceptionally long hair from forehead to withers, creating a ruff or mane) and Tiger Head (larger; shorter hair). As a flock guardian dog in Tibet, and in the West, it uses all the usual livestock guardian tactics (e.g., barking, scent-marking perimeters) to warn away predators and avoid direct confrontations. As

1767-668: The adrenal cortex. Addison's disease is named after Thomas Addison , the British physician who first described the condition in On the Constitutional and Local Effects of Disease of the Suprarenal Capsules (1855). He originally described it as "melasma suprarenale", but later physicians gave it the medical eponym "Addison's disease" in recognition of Addison's discovery. While the six under Addison in 1855 all had adrenal tuberculosis,

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1824-492: The adrenal glands to produce insufficient cortisol. This can be due to damage or destruction of the adrenal cortex. These deficiencies include glucocorticoid and mineralocorticoid hormones as well. These are adrenal dysgenesis (the gland has not formed adequately during development), impaired steroidogenesis (the gland is present but is biochemically unable to produce cortisol), or adrenal destruction (disease processes leading to glandular damage). Darkening ( hyperpigmentation ) of

1881-415: The adrenal glands. In many adult cases it is unclear what has triggered the onset of this disease, though it sometimes follows tuberculosis . Causes can include certain medications, sepsis , and bleeding into both adrenal glands. Addison's disease is generally diagnosed by blood tests , urine tests , and medical imaging . Treatment involves replacing the absent or low hormones. This involves taking

1938-456: The body is strained, as in rigorous exercise or being sick, the latter often needing emergency treatment with intravenous injections to treat the crisis. Individuals with Addison's disease have more than a doubled mortality rate . Furthermore, individuals with Addison's disease and diabetes mellitus have an almost four-fold increase in mortality compared to individuals with only diabetes. The risk ratio for cause mortality in males and females

1995-580: The body, especially lung ), hemorrhage (e.g., in Waterhouse–Friderichsen syndrome or antiphospholipid syndrome ), particular infections ( tuberculosis , histoplasmosis , coccidioidomycosis ), or the deposition of abnormal protein in amyloidosis . All causes in this category are genetic, and generally very rare. These include mutations to the SF1 transcription factor , congenital adrenal hypoplasia due to DAX-1 gene mutations and mutations to

2052-500: The breed suffered because of the limited gene pool from the original stock. By 2015, due to excessive breeding and unsuitability of the breed as a pet in urban situations, prices in China for the best dogs had fallen to about $ 2,000, and both lower quality and crossbreed dogs were being abandoned. In 2011, a DNA study concluded that there was a genetic relationship between the Tibetan mastiff and

2109-424: The cause of adrenal insufficiency in about 35% of diagnosed males with idiopathic Addison's disease and should be considered in the differential diagnosis of any male with adrenal insufficiency. Diagnosis is made by a blood test to detect very long-chain fatty acids . Treatment for Addison's disease involves replacing the missing cortisol, sometimes in the form of hydrocortisone tablets, or prednisone tablets in

2166-741: The darkening of the skin and mucous membranes, particularly in areas exposed to sun or regular friction. Blood tests in people with Addison's disease often reveal low blood sodium . Many also have high blood potassium and/or high thyroid-stimulating hormone (TSH). Most people with Addison's disease develop or have a preexisting autoimmune disease. Particularly common comorbid conditions are autoimmune thyroid disease (40% of people with Addison's), premature ovarian failure (up to 16% of people with Addison's), type 1 diabetes (11%), pernicious anemia (10%), vitiligo (6%) and celiac disease (2%). The combination of Addison's disease in addition to mucocutaneous candidiasis , hypoparathyroidism , or both,

2223-468: The delivery of cholesterol include Smith–Lemli–Opitz syndrome and abetalipoproteinemia . Of the synthesis problems, congenital adrenal hyperplasia is the most common (in various forms: 21-hydroxylase , 17α-hydroxylase , 11β-hydroxylase and 3β-hydroxysteroid dehydrogenase ), lipoid CAH due to deficiency of StAR and mitochondrial DNA mutations. Some medications interfere with steroid synthesis enzymes (e.g., ketoconazole ), while others accelerate

2280-561: The early 20th century, the Prince of Wales, the future George V , introduced a pair of Tibetan Mastiffs to the United Kingdom. By 1906, the breed was prevalent enough in England to be shown at the Crystal Palace show. However, during the war years, the breed lost favor and focus and nearly died out in England. The breed has been gaining in popularity worldwide since 1980. Although the breed

2337-436: The enzyme 21-hydroxylase (a phenomenon first described in 1992). This may be isolated or in the context of autoimmune polyendocrine syndrome (APS type 1 or 2), in which other hormone-producing organs, such as the thyroid and pancreas , may also be affected. Adrenal destruction is also a feature of adrenoleukodystrophy , and when the adrenal glands are involved in metastasis (seeding of cancer cells from elsewhere in

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2394-516: The establishment of a recognized "bandog" breed known today as the Bull Mastiff . The least common "bandog" program in England was funded by Sir Nathanael Dieu-est-Mon'plaisir, the St. Louis Vincent Mastiff or South American Mastiff was named after Vincent Louis who reared plantation dogs originating from St. Louis and other parts of South America. This rare breed is the most expensive mastiff-type dog amongst

2451-433: The face. He is possibly the most famous known case. Hypoadrenocorticism is uncommon in dogs, and rare in cats, with less than 40 known feline cases worldwide, since first documented in 1983. Individual cases have been reported in a grey seal , a red panda , a flying fox, and a sloth. In dogs, hypoadrenocorticism has been diagnosed in many breeds. Vague symptoms, which wax and wane, can cause delay in recognition of

2508-437: The form of a MedicAlert bracelet or information card) for the attention of emergency medical services personnel who might need to attend to their needs. A needle, syringe, and injectable form of cortisol are also recommended to be carried for emergencies. People with Addison's disease are advised to increase their medication during periods of illness or when undergoing surgery or dental treatment. Immediate medical attention

2565-588: The landrace breed throughout its range—the Himalayan mountain dog . It typically retains the hardiness which would be required for it to survive in Tibet, Ladakh and other high-altitude Himalayan regions. Instinctive behaviors, including canine pack behavior, contributed to the survival of the breed in harsh environments. It is one of the few primitive dog breeds that retains a single estrus per year instead of two, even at much lower altitudes and in much more temperate climates than its native climate. This characteristic

2622-401: The most important MSH for skin pigmentation. In secondary and tertiary forms of adrenal insufficiency, skin darkening does not occur, as ACTH is not overproduced. Autoimmune adrenalitis is the most common cause of Addison's disease in the industrialized world as it represents between 68% and 94% of cases. Autoimmune destruction of the adrenal cortex is caused by an immune reaction against

2679-504: The night. Leaving a Tibetan Mastiff outside all night with neighbors nearby is not recommended. They often sleep during the day, making them more active, alert, and aware at night. Like all flock guardian breeds, they are intelligent and stubborn to a fault, so obedience training is recommended (although it is only mildly successful with some individuals) since this is a strong-willed, powerful-bodied breed. Unless they are to be used exclusively as livestock guardians, socialization training

2736-416: The normal breakdown of hormones by the liver (e.g., rifampicin , phenytoin ). Routine laboratory investigations may show: In suspected cases of Addison's disease, demonstration of low adrenal hormone levels even after appropriate stimulation (called the ACTH stimulation test or synacthen test ) with synthetic pituitary ACTH hormone tetracosactide is needed for the diagnosis. Two tests are performed,

2793-793: The owner, in order to avoid mishaps when the dog is merely reacting as a guardian. The breed is not recommended for novice dog owners. Many breeders claim a life expectancy of 10–16 years, but these claims are unsubstantiated. Some lines do produce long-lived dogs. Other, more closely inbred lines, produce short-lived, unhealthy dogs. The breed has fewer genetic health problems than many breeds, but cases can be found of hypothyroidism , entropion , ectropion , distichiasis , skin problems including allergies , autoimmune problems including demodex , Addison's disease , Cushing's disease , missing teeth, malocclusion ( overbite , underbite , dry mouth), cardiac problems, seizures, epilepsy , progressive retinal atrophy (PRA), cataracts , and small ear canals with

2850-439: The person is capable of swallowing fluids and medications by mouth, the amount of glucocorticoids is decreased until a maintenance dose is reached. If aldosterone is deficient, maintenance therapy also includes oral doses of fludrocortisone acetate. Outcomes are typically good when treated. Most people can expect to live relatively normal lives. Someone with the disease should be observant of symptoms of an "Addison's crisis" while

2907-540: The presence of the disease. Female dogs appear more affected than male dogs, though this may not be the case in all breeds. The disease is most often diagnosed in dogs that are young to middle-aged, but it can occur at any age from 4 months to 14 years. Treatment of hypoadrenocorticism must replace the hormones (cortisol and aldosterone) which the dog cannot produce itself. This is achieved either by daily treatment with fludrocortisone , or monthly injections with desoxycorticosterone pivalate (DOCP) and daily treatment with

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2964-406: The short and the long test. Dexamethasone does not cross-react with the assay and can be administered concomitantly during testing. The short test compares blood cortisol levels before and after 250 micrograms of tetracosactide (intramuscular or intravenous) is given. If one hour later, plasma cortisol exceeds 170 nmol/L and has risen by at least 330 nmol/L to at least 690 nmol/L, adrenal failure

3021-584: The similarly large livestock guardian dogs from which they were most likely developed; they also form separate genetic populations . The Fédération Cynologique Internationale and some kennel clubs group the two types together as molossoid dogs; some modern livestock guardian breeds, such as the Pyrenean Mastiff , the Spanish Mastiff and the Tibetan Mastiff , and an extinct draught dog called

3078-519: The skin, including areas not exposed to the sun – characteristic sites of darkening are skin creases (e.g., of the hands), nipple, and the inside of the cheek (buccal mucosa); also, old scars may darken. This occurs because melanocyte-stimulating hormone (MSH) and ACTH share the same precursor molecule, pro-opiomelanocortin (POMC). After production in the anterior pituitary gland, POMC gets cleaved into gamma-MSH, ACTH, and beta-lipotropin . The subunit ACTH undergoes further cleavage to produce alpha-MSH,

3135-467: The sun, oily fish, red meat, and egg yolks among many others. Though there are many sources to obtain vitamin D through diet, supplements are also an option. Standard therapy involves intravenous injections of glucocorticoids and large volumes of intravenous saline solution with dextrose ( glucose ). This treatment usually brings rapid improvement. If intravenous access is not immediately available, intramuscular injection of glucocorticoids can be used. When

3192-459: The term "Addison's disease" does not imply an underlying disease process. The condition was initially considered a form of anemia associated with the adrenal glands. Because little was known at the time about the adrenal glands (then called "Supra-Renal Capsules"), Addison's monograph describing the condition was an isolated insight. As the adrenal function became better known, Addison's monograph became known as an important medical contribution and

3249-556: The two outer layers of the cells of the adrenal glands ( adrenal cortex ), causing adrenal insufficiency . Symptoms generally come on slowly and insidiously and may include abdominal pain and gastrointestinal abnormalities, weakness, and weight loss. Darkening of the skin in certain areas may also occur. Under certain circumstances, an adrenal crisis may occur with low blood pressure , vomiting , lower back pain , and loss of consciousness . Mood changes may also occur. Rapid onset of symptoms indicates acute adrenal failure, which

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