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56-626: Capra ammon Linnaeus, 1758 The argali ( Ovis ammon ), also known as the mountain sheep , is a wild sheep native to the highlands of western East Asia , the Himalayas , Tibet , and the Altai Mountains . The name 'argali' is the Mongolian word for wild sheep. It is the largest species of wild sheep. Argali stand 85 to 135 cm (3 to 4 ft) high at the shoulder and measure 136 to 200 cm (4 to 7 ft) long from

112-529: A dorsal crest and is usually slightly darker in color than the female. Males have two large corkscrew shaped horns, some measuring 190 cm (6 ft 3 in) in total length and weighing up to 23 kg (51 lb). Males use their horns for competing with one another. Females also carry horns, but they are much smaller, usually measuring less than 60 cm (24 in) in total length. Currently, nine argali subspecies are recognized: Genetic analysis of mtDNA of several argali subspecies has shown that

168-445: A few other species have menstrual cycles rather than estrous cycles. Humans, unlike most other species, have concealed ovulation , a lack of obvious external signs to signal estral receptivity at ovulation (i.e., the ability to become pregnant). Some species of animals with estrous cycles have unmistakable outward displays of receptivity, ranging from engorged and colorful genitals to behavioral changes like mating calls . Estrus

224-580: A full set of teeth developing by around six months. By the time their teeth develop, lambs are capable grazers, but the ewes continue nursing them from August to May of the following year. Most argali live five to 10 years, but are capable of living 13 years in the wild. Adult argali eat 16–19 kg (35–42 lb) of food a day. The vegetation preferred by the species varies based on elevation and area. In higher elevations, they predominantly eat grasses , sedges , and forbs . At midelevation habitats, they more regularly feed on bushes and mesophyte grasses . In

280-423: A fully functioning corpus luteum unless they receive coital stimulation. Fertile mating leads to pregnancy in this way, but infertile mating leads to a state of pseudopregnancy lasting about 10 days. Mice and hamsters have similar behavior. The events of the cycle are strongly influenced by lighting periodicity. A set of follicles starts to develop near the end of proestrus and grows at a nearly constant rate until

336-723: A local population, against around 20% adult males and a further 20% young argali. Some rams are solitary, but most are seen in small herds numbering between three and 30 individuals. Females and their young live in larger groups, regularly up to 92 individuals and exceptionally to 200 animals. Migrating herds, especially males, have been reported. Most migration appear to be related to seasonally decreased food sources, though an overabundance of biting insects, especially horseflies , severe drought or fires, poaching by humans, and large numbers of domestic livestock may also trigger movements. With their long legs, herds can travel quickly from place to place. Argali tend to live at higher elevations during

392-407: A major threat. It has been extirpated in northeastern China , southern Siberia and parts of Mongolia . In Azad Jammu and Kashmir , it is listed as an endangered species. Findings in the mitochondrial genome relationship and the development of interspecies nuclear transfer embryos between argali and sheep could help in conserving the species in the long run. Ovis See text . Ovis

448-663: A mature bighorn ram can weigh 14 kg (31 lb) – as much as the bones of the rest of its body put together. Rams use their horns to fight with each other for dominance and the right to mate with females. In most cases, they do not injure each other because they hit each other head-to-head, and their curved horns do not strike each other's bodies. They are also protected by having very thick skin and double-layered skulls. Wild sheep have very keen senses of sight and hearing . When detecting predators, wild sheep most often flee, usually to higher ground, but they can also fight back. The Dall sheep has been known to butt wolves off

504-559: A possibly predatory manner and remains of argali lambs have been observed in golden eagle nests. Smaller predators, such as raptorial birds and smaller mammalian carnivores, are attacked by mother ewes, but in the presence of larger predators, the ewes quickly run away with the lambs following them. The argali is listed as Near Threatened on the IUCN Red List . It is hunted for its meat and horns, which are used in traditional traditional Chinese medicine , and poaching continues to be

560-553: A pregnancy, some species have postpartum estrus , which is ovulation and corpus luteum production that occurs immediately following the birth of the young. For example, the mouse has a fertile postpartum estrus that occurs 14 to 24 hours following parturition. Estrous cycle variability differs among species, but cycles are typically more frequent in smaller animals. Even within species significant variability can be observed, thus cats may undergo an estrous cycle of 3 to 7 weeks. Domestication can affect estrous cycles due to changes in

616-458: A reddish-brown to a dark grey-brown. Argali or nyan from the Himalayas are usually relatively dark, whereas those from Russian ranges are often relatively pale. In summertime, the coat is often lightly spotted with a salt-and-pepper pattern. The back is darker than the sides, which gradually lighten in color. The face, tail and the buttocks are yellowish-white. The male has a whitish neck ruff and

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672-465: A situation that may be signaled by visible physiologic changes. Estrus is commonly seen in the mammalian species, including some primates. In some species, the vulva becomes swollen and reddened. Ovulation may occur spontaneously in others. Especially among quadrupeds , a signal trait of estrus is the lordosis reflex , in which the animal spontaneously elevates her hindquarters. Controlled internal drug release devices are used in livestock for

728-404: A time. Other behaviors of the female during standing estrus may change, including, but not limited to: nervousness, swollen vulva , or attempting to mount other animals. While visual and behavioral cues are helpful to the male cattle, estrous stages cannot be determined by the human eye. Rather, the stage can be estimated from the appearance of the corpora lutea or follicle composition. Due to

784-441: A vital role in digesting food; they eructate , and rechew the cud to enable them to digest and live on low-quality, rough plant materials. Sheep conserve water well, and can live in fairly dry environments. The bodies of wild sheep (and some domestic breeds) are covered by a coat of thick hair to protect them from cold. This coat contains long, stiff hairs, called kemps, over a short, woolly undercoat, which grows in autumn and

840-524: Is characterized by males competing for females in estrus. Social rank in rams is established by male-male competition during the rutting period. Females select from dominant males based on sexually selected characteristics such as body size and horn size, as those traits are desirable in offspring. Females typically are separated from males outside the rut, but during the rut, females and males are found together. Females that are oestrous isolate themselves from other ewes, and may be less mobile. The rut

896-617: Is ovine , and the collective term for sheep is flock or mob . The term herd is also occasionally used in this sense, generally for large flocks. Many specialist terms relating to domestic sheep are used. Sheep are fairly small compared to other ungulates ; in most species, adults weigh less than 100 kg (220 lb). Males are usually heavier than females by a significant amount. Wild sheep are mostly found in hilly or mountainous habitats. Their diets consist mainly of grasses , as well as other plants and lichens . Like other ruminants , they have four-chambered stomachs , which play

952-560: Is a genus of mammals , part of the Caprinae subfamily of the ruminant family Bovidae . Its seven highly sociable species are known as sheep or ovines . Domestic sheep are members of the genus, and are thought to be descended from the wild mouflon of central and southwest Asia . Female sheep are called ewes , males are called rams or less frequently bucks or tups , neutered males are called wethers , and young sheep are called lambs . The adjective applying to sheep

1008-455: Is also linked with different ewe behaviour than during nonrutting periods. These changes are characterized by decreased feeding, increased time observing their surroundings, and increased behaviour changes. Ewes are also predicted to be slightly receptive to the displays of the rams. Estrus Mammals share the same reproductive system, including the regulatory hypothalamic system that produces gonadotropin-releasing hormone in pulses,

1064-526: Is called early diestrus or diestrus I. During this day, the corpora lutea grow to a maximal volume, achieved within 24 hours of ovulation. They remain at that size for three days, halve in size before the metestrus of the next cycle and then shrink abruptly before estrus of the cycle after that. Thus the ovaries of cycling rats contain three different sets of corpora lutea at different phases of development. Buffalo have an estrous cycle of about 22 to 24 days. Buffalo are known for difficult estrus detection. This

1120-416: Is common and is believed to be caused by diapedesis of red blood cells from the blood vessels due to the increase of the estradiol-17β hormone . A mare may be in heat for 4 to 10 days, followed by approximately 14 days in diestrus. Thus, a cycle may be short, totaling approximately 3 weeks. Horses mate in spring and summer; autumn is a transition time, and anestrus occurs during winter. A feature of

1176-492: Is derived via Latin oestrus (' frenzy ', ' gadfly '), from Greek οἶστρος oîstros (literally 'gadfly', more figuratively 'frenzy', 'madness', among other meanings like 'breeze'). Specifically, this refers to the gadfly in Ancient Greek mythology that Hera sent to torment Io , who had been won in her heifer form by Zeus . Euripides used oestrus to indicate 'frenzy', and to describe madness. Homer used

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1232-483: Is one major reason for being less productive than cattle . During four phases of its estrous cycle, mean weight of corpus luteum has been found to be 1.23±0.22g (metestrus), 3.15±0.10g (early diestrus), 2.25±0.32g (late diestrus), and 1.89±0.31g (proestrus/estrus), respectively. The plasma progesterone concentration was 1.68±0.37, 4.29±0.22, 3.89±0.33, and 0.34±0.14 ng/ml while mean vascular density (mean number of vessels/10 microscopic fields at 400x) in corpus luteum

1288-453: Is relatively long at 5 to 9 days, while the estrus may last 4 to 13 days, with a diestrus of 60 days followed by about 90 to 150 days of anestrus. Female dogs bleed during estrus, which usually lasts from 7–13 days, depending on the size and maturity of the dog. Ovulation occurs 24–48 hours after the luteinizing hormone peak, which occurs around the fourth day of estrus; therefore, this is the best time to begin breeding. Proestrus bleeding in dogs

1344-612: Is shed in spring. This woolly undercoat has been developed in many domestic sheep breeds into a fleece of long wool , with selection against kemp hairs in these breeds. The fleece covers the body (in a few breeds also the face and legs) and is used for fibre . Domestic sheep are also reared for their milk and meat (which is called lamb or mutton depending on the age of the animal). In wild sheep, both rams and ewes have horns , while in domestic sheep (depending upon breed ) horns may be present in both rams and ewes, in rams only, or in neither. Rams' horns may be very large – those of

1400-457: Is the combined stages of diestrus and anestrus, before reentering estrus. With the induction of ovulation, the female becomes pregnant or undergoes a non-pregnant luteal phase , also known as pseudopregnancy . Cats are polyestrous but experience a seasonal anestrus in autumn and late winter. A female dog is usually diestrous (goes into heat typically twice per year), although some breeds typically have one or three cycles per year. The proestrus

1456-413: Is the largest race on average, regularly measuring more than 180 cm (5 ft 11 in) long without the tail, and is less sexually dimorphic in body mass than most other subspecies. The argali has relatively the shortest tail of any wild goat-antelope or sheep , with reported tail lengths of 9.5–17 cm (3.7–6.7 in). The general coloration varies between each animal, from a light yellow to

1512-482: Is thought to act by regulating the hypothalamic pulse activity of the gonadotropin-releasing hormone . Anestrus is induced by time of year, pregnancy , lactation , significant illness , chronic energy deficit, and possibly age. Chronic exposure to anabolic steroids may also induce a persistent anestrus due to negative feedback on the hypothalamus/pituitary/gonadal axis. Other spellings include anoestrus , anestrum , and anoestrum . After completion (or abortion) of

1568-417: The fertility cycle of horses and other large herd animals is that it is usually affected by the seasons. The number of hours daily that light enters the eye of the animal affects the brain, which governs the release of certain precursors and hormones. When daylight hours are few, these animals "shut down", become anestrous, and do not become fertile. As the days grow longer, the longer periods of daylight cause

1624-419: The offspring during the warm season to aid survival during the next winter. A few mammalian species, such as rabbits , do not have an estrous cycle, instead being induced to ovulate by the act of mating and are able to conceive at almost any arbitrary moment. Generally speaking, the timing of estrus is coordinated with seasonal availability of food and other circumstances such as migration, predation etc.,

1680-406: The ovary start to grow. Their number is species-specific. Typically, this phase can last as little as one day or as long as three weeks, depending on the species. Under the influence of estrogen, the lining of the uterus ( endometrium ) starts to develop. Some animals may experience vaginal secretions that could be bloody. The female is not yet sexually receptive; the old corpus luteum degenerates;

1736-426: The pituitary gland that secretes follicle-stimulating hormone and luteinizing hormone , and the ovary itself that releases sex hormones , including estrogens and progesterone . However, animals that have estrous cycles resorb the endometrium if conception does not occur during that cycle. Mammals that have menstrual cycles shed the endometrium through menstruation instead. Humans, elephant shrews , and

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1792-724: The Altai and Gobi argalis grouped closely with the urial subspecies O. vignei bochariensis , while the Karaganda and Kara Tau argalis grouped with the urial subspecies O. vignei arkal . Argali range from central Kazakhstan in the west to the Shanxi Province in China in the east and from the Altai Mountains in the north to the Himalayas to the south. They are a species of mountainous areas, living from elevations of 300 to 5,800 m (980 to 19,030 ft). In protected areas,

1848-412: The air, exerting enough force to be heard up to 800 m (2,600 ft) away. Often, the older males (over six years of age), which are also often the largest, end up the dominant ones and younger males are chased off once the ewes are in estrus . Once dominance is established, the top rams begin approaching ewes and smell their urine to determine their receptiveness . The ram then repeatedly approaches

1904-697: The available methods of cattle estrous synchronization. Treatment depends on herd size, specific goals for control, and budget. Some of the FDA -approved drugs and devices used to mimic natural hormones of the estrous cycle include, but are not limited to, the following classes: There is variation between the available methods of cattle estrous synchronization. Treatment depends on herd size, specific goals for control, and budget. Bovine estrous cycles may also be impacted by other bodily functions such as oxytocin levels. Additionally, heat stress has been linked to impairment of follicular development, especially impactful to

1960-419: The beginning of the subsequent estrus when the growth rates accelerate eightfold. Ovulation occurs about 109 hours after the start of follicle growth. Estrogen peaks at about 11 am on the day of proestrus. Between then and midnight there is a surge in progesterone , luteinizing hormone and follicle-stimulating hormone , and ovulation occurs at about 4 am on the next estrus day. The following day, metestrus,

2016-666: The environment. For most species, vaginal smear cytology may be used in order to identify estrous cycle phases and durations. Some species, such as cats , cows and domestic pigs , are polyestrous , meaning that they can go into heat several times per year. Seasonally polyestrous animals or seasonal breeders have more than one estrous cycle during a specific time of the year and can be divided into short-day and long-day breeders: Species that go into heat twice per year are diestrous . Canines are diestrous. Monestrous species, such as canids and bears , have only one breeding season per year, typically in spring to allow growth of

2072-486: The ewe and forcibly mounts her. Mating commences around two to three weeks after the rutting begins. Rams may remain in the company of ewes for up to two months after the rutting period is complete. The gestation period lasts a little over 165 days. Births occur in late March or April, with a variable number of females being barren. Most subspecies give birth to a single lamb, though in some races, twins are not uncommon and even as many as five have been born at once. At birth,

2128-653: The face of cliffs. Sheep have scent glands on their faces and feet. Communication through the scent glands is not well understood, but is thought to be important for sexual signaling. Males can smell females that are in estrus , and rams mark their territories by rubbing scent on rocks. Seven species (and numerous subspecies) of sheep are currently recognized. The main recognized divisions are: Sheep are social animals and live in groups, called flocks. This helps them to avoid predators and stay warm in cold weather by huddling together. Flocks of sheep need to keep moving to find new grazing areas and more favourable weather as

2184-478: The goal being to maximize the offspring's chances of survival. Some species are able to modify their estral timing in response to external conditions. The female cat in heat has an estrus of 14 to 21 days and is generally characterized as an induced ovulator , since coitus induces ovulation. However, various incidents of spontaneous ovulation have been documented in the domestic cat and various non-domestic species. Without ovulation, she may enter interestrus, which

2240-471: The head to the base of the tail. The female, or ewe is the smaller sex by a considerable margin, sometimes weighing less than half as much as the male, or ram . The ewes can weigh from 43.2 to 100 kg (95 to 220 lb) and the rams typically from 97 to 328 kg (214 to 723 lb), with a maximum reported mass of 356 kg (785 lb). The Pamir argali (also called Marco Polo sheep , for they were first described by that traveler), O. a. polii ,

2296-399: The hormones that activate the breeding cycle to be released. As it happens, this benefits these animals in that, given a gestation period of about eleven months, it prevents them from having young when the cold of winter would make their survival risky. Rats are polyestrous animals that typically have rapid cycle lengths of 4 to 5 days. Although they ovulate spontaneously, they do not develop

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2352-588: The lambs weigh 2.7–4.6 kg (6.0–10.1 lb). The newborn lamb and mother ewe stay around where the birth occurs overnight and, on the next day, both usually walk together. Lambs often play in groups, jumping up and down together, sometimes being joined by their mothers. Weight gain is often quite fast and the lambs may weigh 10 times their birth weight by their first birthday. Females often attain their maximum mass by two years of age, but males appear to continue to grow larger and heavier in their third and fourth years. Milk teeth develop around three months of age, with

2408-672: The lowest ranges and the spurs of deserts, grasses and sedges again predominate, but often of different species than the high-elevation ones. In north-central Kazakhstan, sprouts, leaves, flowers, and fruits are significant to the diet all year, whereas they appear to be a rare dietary supplement over the rest of the range. Water is needed by argali, which is rarely a problem for animals living at high elevation, where melting snow and small waterways are regularly encountered. In drier climes, argali may travel several kilometers in search of water. When available, argali readily consume saline soil. Although they are locally sympatric with Siberian ibex ,

2464-446: The mountains where snow cover is not heavy during the winter, following winds that blow snow off the earth. Rams are generally found at higher elevations more regularly than females and stay at higher elevations longer during the winter. Argalis live in herds typically numbering between two and 150 animals, segregated by sex, except during breeding season. Most populations show large numbers of adult females, constituting more than half of

2520-402: The seasons change. In each flock, a sheep, usually a mature ram, is followed by the others. This "leader to follower" relationship can be both a positive and negative for flocks of Ovis aries . Although there is safety in numbers, it has been reported that the following of one mature ram can bring flocks to slaughter in many situations where the mature ram misguides the flock. Mating in sheep

2576-511: The species generally prefers gently sloping areas with soft broken terrain, although ewes with lambs often take up residence in more precipitous areas, characterized by canyons and jagged rocks. In areas where they are extensively hunted (such as Kazakhstan), they are more likely to be found in forested areas. In parts of China and Russia where they compete for resources with numerous domestic stock, argali more regularly take up residence in precipitous, jagged areas. Argali may search for regions in

2632-462: The summer. Argali reach breeding maturity at two to three years of age. Rutting may occur from October to mid-January, generally lasting longer in lower elevations. In rutting herds, both rams and ewes attack others of their own sex, exerting dominance by ramming each other with their horns. Although such groups engage in lamb-like play, the combat of a pair of mature males is a serious business. The rams slam into each other, with their fore legs up in

2688-401: The synchronization of estrus. This phase is characterized by the activity of the corpus luteum , which produces progesterone. The signs of estrogen stimulation subside and the corpus luteum starts to form. The uterine lining begins to appear. In the absence of pregnancy , the diestrus phase (also termed pseudopregnancy ) terminates with the regression of the corpus luteum. The lining in

2744-582: The two species have differing habitat and pasture preferences, reducing likely competition. In Tibet , the argali must regularly compete with other grazing species for pasture, including Tibetan antelope , bharal , Thorold's deer and wild yaks . Competition is most serious with livestock, especially domestic yaks and domestic sheep , with which argali are frequently forced to intermingle and from which they often catch diseases and parasites. The main predators of argali are Himalayan wolves , which often exploit harsh winter conditions (such as deep snow) to capture

2800-784: The uterus and the vagina distend and fill with fluid, become contractile and secrete a sanguinous fluid; the vaginal epithelium proliferates and the vaginal cytology shows a large number of non-cornified nucleated epithelial cells. Variant terms for proestrus include pro-oestrus , proestrum , and pro-oestrum . Estrus or oestrus refers to the phase when the female is sexually receptive (" in heat " in American English, or " on heat " in British English). Under regulation by gonadotropic hormones , ovarian follicles mature and estrogen secretions exert their biggest influence. The female then exhibits sexually receptive behavior,

2856-483: The uterus is not shed, but is reorganized for the next cycle. Other spellings include metoestrus , metestrum , metoestrum , dioestrus , diestrum , and dioestrum . Anestrus refers to the phase when the sexual cycle rests. This is typically a seasonal event and controlled by light exposure through the pineal gland that releases melatonin . Melatonin may repress stimulation of reproduction in long-day breeders and stimulate reproduction in short-day breeders. Melatonin

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2912-416: The widespread use of bovine animals in agriculture, cattle estrous cycles have been widely studied, and manipulated, in an effort to maximize profitability through reproductive management. Much estrous control in cattle is for the purpose of synchronization, a practice or set of practices most often used by cattle farmers to control the timing and duration of estrus in large herds. There is variation between

2968-467: The wild sheep, though they can and do take specimens of any age or condition year around. Snow leopards and leopards are also predators of argali of any age. Eurasian lynx and wolverines may seldom kill argali to at least the size of winter-weakened ewes. Red foxes and domestic dogs (largely those kept by sheep-herders) will prey on lambs. Cinereous vultures , lammergeiers and golden eagles have been observed circling herds of ewes with lambs in

3024-460: The word to describe panic. Plato also used it to refer to an irrational drive and to describe the soul "driven and drawn by the gadfly of desire". Somewhat more closely aligned to current meaning and usage of estrus , Herodotus ( Histories , ch. 93.1) uses oîstros to describe the desire of fish to spawn . The earliest use in English was with a meaning of 'frenzied passion'. In 1900, it

3080-517: Was 6.33±0.99, 18.00±0.86, 11.50±0.76, and 2.83±0.60 during the metestrus, early diestrus, late diestrus and proestrus/estrus, respectively. Female cattle, also referred to as " heifers " in agriculture, will gradually enter standing estrus, or "standing heat," starting at puberty between 9 and 15 months of age. The cow estrous cycle typically lasts 21 days. Standing estrus is a visual cue which signifies sexual receptivity for mounting by male cattle. This behavior lasts anywhere between 8 and 30 hours at

3136-557: Was first used to describe ' rut in animals; heat'. In British English , the spelling is oestrus or (rarely) œstrus . In all English spellings, the noun ends in -us and the adjective in -ous . Thus in Modern International English , a mammal may be described as "in estrus" when it is in that particular part of the estrous-cycle . [REDACTED] A four-phase terminology is used in reference to animals with estrous cycles. One or several follicles of

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