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Dzo
A dzo (also spelled zo, zho and dzho, bo, མཛོ་, mdzo) is a hybrid between the yak and domestic cattle. The word dzo technically refers to a male hybrid, while a female is known as a or . In Mongolian, it is called a (хайнаг). There is also the English language portmanteau term of yattle, a combination of the words yak and cattle, as well as yakow, a combination of the words yak and cow. Dzomo are fertile (or, fecund) while dzo are sterile. As they are a product of the hybrid genetic phenomenon of heterosis (hybrid vigor), they are larger and stronger than yak or cattle from the region. In Mongolia and Tibet, khainags are thought to be more productive than cattle or yaks in terms of both milk and meat production. Dzomo can be back crossed. As a result, many supposedly pure yak or pure cattle probably carry each other's genetic material. In Mongolia, the result of a crossed with either a domestic bull or yak bull is called (ортоом, three-quarter-bre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yakalo
The yakalo is a cross of the yak (''Bos grunniens'') and the American bison (''Bison bison'', known as a buffalo in North America). It was produced by hybridisation experiments in the 1920s, when crosses were made between yak bulls and both pure bison cows and bison-cattle hybrid cows. As with many other inter-specific crosses, only female hybrids were found to be fertile ( Haldane's rule). Few of the hybrids survived, and the experiments were discontinued in 1928.Deakin, A, Muir, G W, Smith, A G (1935). "Hybridization of domestic cattle, bison and yak. Report of Wainwright experiment". ''Publication 479, Technical Bulletin 2'', Dominion of Canada, Department of Agriculture, Ottawa; cited in: Weiner, Gerald (2003)''The Yak, Second Edition'' FAO RAP Publication, pp. 18, 338. See also * Beefalo * Dzo * Żubroń Żubroń (; pl, żubroń ) is a hybrid of domestic cattle and wisent. The wisent (''żubr'' in Polish) is the European bison; hence, the żubroń is analogous to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bovid Hybrid
A bovid hybrid is a hybrid of two different members of the bovid family. ''Bos'' hybrids Hybrids between bison and domestic cattle The American bison and European bison (wisent) have been hybridized with domestic cattle. European bison With wisent, this was originally done in an attempt to reinvigorate the declining wisent population. First generation hybrid males are sterile, but females may be crossed back to either a wisent or domestic bull to produce fertile males. Modern wisent herds keep hybrids well isolated from pure wisent. However, since the modern purebred wisent descend from fewer than two dozen individuals, a significant genetic bottleneck has resulted for the purebred wisent. European bison (wisent) have also been crossed with domestic cattle to produce the . These were first bred in Poland in 1847 as hardy, disease resistant alternatives to domestic cattle. Breeding was discontinued in the 1980s. The few remaining can be found at Bialowieski National P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fertility
Fertility is the capability to produce offspring through reproduction following the onset of sexual maturity. The fertility rate is the average number of children born by a female during her lifetime and is quantified demographically. Fertility is addressed when there is a difficulty or an inability to reproduce naturally, which is referred to as infertility. Infertility is widespread, with fertility specialists available all over the world to assist mothers and couples who experience difficulties having a baby. Human fertility depends on factors of nutrition, sexual behaviour, consanguinity, culture, instinct, endocrinology, timing, economics, personality, way of life, and emotions. Fertility differs from fecundity, which is defined as the ''potential'' for reproduction (influenced by gamete production, fertilization and carrying a pregnancy to term). Where a woman or the lack of fertility is infertility while a lack of fecundity would be called sterility. Demography I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mongolia
Mongolia; Mongolian script: , , ; lit. "Mongol Nation" or "State of Mongolia" () is a landlocked country in East Asia, bordered by Russia to the north and China to the south. It covers an area of , with a population of just 3.3 million, making it the world's most sparsely populated sovereign nation. Mongolia is the world's largest landlocked country that does not border a closed sea, and much of its area is covered by grassy steppe, with mountains to the north and west and the Gobi Desert to the south. Ulaanbaatar, the capital and largest city, is home to roughly half of the country's population. The territory of modern-day Mongolia has been ruled by various nomadic empires, including the Xiongnu, the Xianbei, the Rouran, the First Turkic Khaganate, and others. In 1206, Genghis Khan founded the Mongol Empire, which became the largest contiguous land empire in history. His grandson Kublai Khan conquered China proper and established the Yuan dynasty. After the co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Backcrossing
Backcrossing is a crossing of a hybrid with one of its parents or an individual genetically similar to its parent, to achieve offspring with a genetic identity closer to that of the parent. It is used in horticulture, animal breeding, and production of gene knockout organisms. Backcrossed hybrids are sometimes described with acronym "BC"; for example, an F1 hybrid crossed with one of its parents (or a genetically similar individual) can be termed a BC1 hybrid, and a further cross of the BC1 hybrid to the same parent (or a genetically similar individual) produces a BC2 hybrid. Plants Advantages * If the recurrent parent is an elite genotype, at the end of the backcrossing programme, an elite genotype is recovered. * As no "new" recombination results, the elite combination is not lost. Disadvantages * It works poorly for quantitative traits. * It is more restricted for recessive traits. * In practice, sections of genome from the nonrecurrent parents are often still present and c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterosis
Heterosis, hybrid vigor, or outbreeding enhancement is the improved or increased function of any biological quality in a hybrid offspring. An offspring is heterotic if its traits are enhanced as a result of mixing the genetic contributions of its parents. These effects can be due to Mendelian or non-Mendelian inheritance. Definitions In proposing the term heterosis to replace the older term heterozygosis, G.H. Shull aimed to avoid limiting the term to the effects that can be explained by heterozygosity in Mendelian inheritance. Heterosis is often discussed as the opposite of inbreeding depression, although differences in these two concepts can be seen in evolutionary considerations such as the role of genetic variation or the effects of genetic drift in small populations on these concepts. Inbreeding depression occurs when related parents have children with traits that negatively influence their fitness largely due to homozygosity. In such instances, outcrossing shoul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sterility (physiology)
Sterility is the physiological inability to effect sexual reproduction in a living thing, members of whose kind have been produced sexually. Sterility has a wide range of causes. It may be an inherited trait, as in the mule; or it may be acquired from the environment, for example through physical injury or disease, or by exposure to radiation. Sterility is the inability to produce a biological child, while infertility is the inability to conceive after a certain period. Sterility is rarely discussed in clinical literature and is often used synonymously with infertility. Infertility affects about 12-15% of couples globally. Still, the prevalence of sterility remains unknown. Sterility can be divided into three subtypes natural, clinical, and hardship. Natural sterility is the couple’s physiological inability to conceive a child naturally. Clinical sterility is natural sterility for which treatment of the patient will not result in conception. Hardship sterility is the inability to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fecundity
Fecundity is defined in two ways; in human demography, it is the potential for reproduction of a recorded population as opposed to a sole organism, while in population biology, it is considered similar to fertility, the natural capability to produce offspring, measured by the number of gametes (eggs), seed set, or asexual propagules. Superfecundity refers to an organism's ability to store another organism's sperm (after copulation) and fertilize its own eggs from that store after a period of time, essentially making it appear as though fertilization occurred without sperm (i.e. parthenogenesis). Human demography Human demography considers only human fecundity, at its culturally differing rates, while population biology studies all organisms. The term ''fecundity'' in population biology is often used to describe the rate of offspring production after one time step (often annual). In this sense, fecundity may include both birth rates and survival of young to that time step. Whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ISO 639-3
ISO 639-3:2007, ''Codes for the representation of names of languages – Part 3: Alpha-3 code for comprehensive coverage of languages'', is an international standard for language codes in the ISO 639 series. It defines three-letter codes for identifying languages. The standard was published by International Organization for Standardization (ISO) on 1 February 2007. ISO 639-3 extends the ISO 639-2 alpha-3 codes with an aim to cover all known natural languages. The extended language coverage was based primarily on the language codes used in the ''Ethnologue'' (volumes 10–14) published by SIL International, which is now the registration authority for ISO 639-3. It provides an enumeration of languages as complete as possible, including living and extinct, ancient and constructed, major and minor, written and unwritten. However, it does not include reconstructed languages such as Proto-Indo-European. ISO 639-3 is intended for use as metadata codes in a wide range of applications. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pack Animal
A pack animal, also known as a sumpter animal or beast of burden, is an individual or type of working animal used by humans as means of transporting materials by attaching them so their weight bears on the animal's back, in contrast to draft animals which pull loads but do not carry them. Traditional pack animals are diverse including camels, goats, yaks, reindeer, water buffaloes, and llamas as well as the more familiar pack animals like dogs, horses, donkeys, and mules. Nomenclature The term ''pack animal'' is traditionally used in contrast to ''draft animal'', which is a working animal that typically pulls a load behind itself (such as a plow, a cart, a sled or a heavy log) rather than carrying cargo directly on its back. For instance, sled dogs pull loads but do not normally carry them, while working elephants have been used for centuries to haul logs out of forests. The term ''pack animal'' can also refer to animals which naturally live and hunt in packs in the wild, such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Washington Post
''The Washington Post'' (also known as the ''Post'' and, informally, ''WaPo'') is an American daily newspaper published in Washington, D.C. It is the most widely circulated newspaper within the Washington metropolitan area and has a large national audience. Daily broadsheet editions are printed for D.C., Maryland, and Virginia. The ''Post'' was founded in 1877. In its early years, it went through several owners and struggled both financially and editorially. Financier Eugene Meyer purchased it out of bankruptcy in 1933 and revived its health and reputation, work continued by his successors Katharine and Phil Graham (Meyer's daughter and son-in-law), who bought out several rival publications. The ''Post'' 1971 printing of the Pentagon Papers helped spur opposition to the Vietnam War. Subsequently, in the best-known episode in the newspaper's history, reporters Bob Woodward and Carl Bernstein led the American press's investigation into what became known as the Watergate scandal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portmanteau Word
A portmanteau word, or portmanteau (, ) is a blend of wordsGarner's Modern American Usage , p. 644. in which parts of multiple words are combined into a new word, as in ''smog'', coined by blending ''smoke'' and ''fog'', or ''motel'', from ''motor'' and ''hotel''. In , a portmanteau is a single morph that is analyzed as representing two (or more) underlying s. When portmanteaus shorten es ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
