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32-530: The Parthenaise is a French breed of beef cattle . It is named for the town of Parthenay in the département of Deux-Sèvres , in the Nouvelle-Aquitaine region of western France. It was formerly a triple-purpose breed, raised for milk, meat and draught work , but is now raised mainly for beef . The Parthenaise forms a part of the large population – sometimes called Poitevine or Vendéenne – of wheaten-coloured cattle which traditionally occupied

64-457: A skeletal muscle developmental deficit. In population genetics , the concept of heterozygosity is commonly extended to refer to the population as a whole, i.e., the fraction of individuals in a population that are heterozygous for a particular locus. It can also refer to the fraction of loci within an individual that are heterozygous. In an admixed population , whose members derive ancestry from two or more separate sources, its heterozygosity

96-556: A diploid organism is hemizygous when only one copy is present. The cell or organism is called a hemizygote . Hemizygosity is also observed when one copy of a gene is deleted, or, in the heterogametic sex , when a gene is located on a sex chromosome. Hemizygosity is not the same as haploinsufficiency , which describes a mechanism for producing a phenotype. For organisms in which the male is heterogametic, such as humans, almost all X-linked genes are hemizygous in males with normal chromosomes, because they have only one X chromosome and few of

128-422: A gene often varies from one individual to another. These gene variants are called alleles . While some genes have only one allele because there is low variation, others have only one allele because deviation from that allele can be harmful or fatal. But most genes have two or more alleles. The frequency of different alleles varies throughout the population. Some genes may have alleles with equal distributions. Often,

160-432: A genotype consisting of only a single copy of a particular gene in an otherwise diploid organism, and nullizygous refers to an otherwise-diploid organism in which both copies of the gene are missing. A cell is said to be homozygous for a particular gene when identical alleles of the gene are present on both homologous chromosomes . An individual that is homozygous-dominant for a particular trait carries two copies of

192-418: A heterozygote will express only the trait coded by the dominant allele, and the trait coded by the recessive allele will not be present. In more complex dominance schemes the results of heterozygosity can be more complex. A heterozygous genotype can have a higher relative fitness than either the homozygous-dominant or homozygous-recessive genotype – this is called a heterozygote advantage . A chromosome in

224-401: A matching pair and that a few chromosomes may be mismatched as part of a chromosomal sex-determination system . If both alleles of a diploid organism are the same, the organism is homozygous at that locus. If they are different, the organism is heterozygous at that locus. If one allele is missing, it is hemizygous , and, if both alleles are missing, it is nullizygous . The DNA sequence of

256-402: A population: where n {\displaystyle n} is the number of individuals in the population, and a i 1 , a i 2 {\displaystyle a_{i1},a_{i2}} are the alleles of individual i {\displaystyle i} at the target locus. where m {\displaystyle m} is the number of alleles at

288-505: A single oocyte which subsequently splits into two morula . Zygosity is an important factor in human medicine. If one copy of an essential gene is mutated, the (heterozygous) carrier is usually healthy. However, more than 1,000 human genes appear to require both copies, that is, a single copy is insufficient for health. This is called haploinsufficiency . For instance, a single copy of the Kmt5b gene leads to haploinsufficiency and results in

320-400: A specific genotype. Heterozygous genotypes are represented by an uppercase letter (representing the dominant/wild-type allele) and a lowercase letter (representing the recessive/mutant allele), as in "Rr" or "Ss". Alternatively, a heterozygote for gene "R" is assumed to be "Rr". The uppercase letter is usually written first. If the trait in question is determined by simple (complete) dominance,

352-419: Is homozygous-recessive for a particular trait carries two copies of the allele that codes for the recessive trait . This allele, often called the "recessive allele", is usually represented by the lowercase form of the letter used for the corresponding dominant trait (such as, with reference to the example above, "p" for the recessive allele producing white flowers in pea plants). The genotype of an organism that

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384-421: Is different from Wikidata Use dmy dates from May 2015 Use list-defined references from May 2015 EngvarB from May 2015 Homozygous Most eukaryotes have two matching sets of chromosomes ; that is, they are diploid . Diploid organisms have the same loci on each of their two sets of homologous chromosomes except that the sequences at these loci may differ between the two chromosomes in

416-406: Is homozygous-recessive for a particular trait is represented by a doubling of the appropriate letter, such as "pp". A diploid organism is heterozygous at a gene locus when its cells contain two different alleles (one wild-type allele and one mutant allele) of a gene. The cell or organism is called a heterozygote specifically for the allele in question, and therefore, heterozygosity refers to

448-595: Is irrelevant for them. As discussed above, "zygosity" can be used in the context of a specific genetic locus (example ). The word zygosity may also be used to describe the genetic similarity or dissimilarity of twins. Identical twins are monozygotic , meaning that they develop from one zygote that splits and forms two embryos. Fraternal twins are dizygotic because they develop from two separate oocytes (egg cells) that are fertilized by two separate sperm . Sesquizygotic twins are halfway between monozygotic and dizygotic and are believed to arise after two sperm fertilize

480-476: Is known as being "identical by state", or IBS. Because the alleles of autozygous genotypes come from the same source, they are always homozygous, but allozygous genotypes may be homozygous too. Heterozygous genotypes are often, but not necessarily, allozygous because different alleles may have arisen by mutation some time after a common origin. Hemizygous and nullizygous genotypes do not contain enough alleles to allow for comparison of sources, so this classification

512-597: Is proven to be at least as great as the least heterozygous source population and potentially more than the heterozygosity of all the source populations. It reflects the contributions of its multiple ancestral groups. Admixed populations show high levels of genetic variation due to the fusion of source populations with different genetic variants. Typically, the observed ( H o {\displaystyle H_{o}} ) and expected ( H e {\displaystyle H_{e}} ) heterozygosities are compared, defined as follows for diploid individuals in

544-498: The Chinese hamster ovary cell line, a number of genetic loci are present in a functional hemizygous state, due to mutations or deletions in the other alleles. A nullizygous organism carries two mutant alleles for the same gene. The mutant alleles are both complete loss-of-function or 'null' alleles, so homozygous null and nullizygous are synonymous. The mutant cell or organism is called a nullizygote . Zygosity may also refer to

576-534: The Gâtine Vendéenne . At the end of their working lives, these oxen were often sent to the area of Cholet to be fattened for slaughter, and then were known as 'Choletaises'. The name of the breed is due to Eugène Gayot  [ fr ] , who in 1860 identified Parthenay , in the département of Deux-Sèvres , as the principal centre of production. In the second half of the nineteenth century many vineyards were destroyed by phylloxera and uprooted;

608-413: The mucosa , the hooves, the switch and the edges of the ears. The horns are lyre-shaped. The Parthenise was traditionally a triple-purpose breed, reared for draught work , for milk and for meat . From 1971 selection was for beef only. Calves reach an average weight of 165 kg at 120 days, and average about 278 kg at 210 days. List of French cattle breeds From Misplaced Pages,

640-2138: The Food and Agriculture Organization of the United Nations. Accessed May 2015. v t e Cattle breeds of France These are the cattle breeds considered in France to be wholly or partly of French origin. Inclusion here does not necessarily imply that a breed is predominantly or exclusively French. Abondance Alpha 16 Armoricaine Aubrac Bazadaise Béarnaise Betizu Bleue de Bazougers Bleue du Nord Blonde d'Aquitaine Bordelais (extinct) Bordelaise Brava Bretonne Pie Noir Brune or French Brown Casta or Aure et Saint-Girons Charolais Corsican Créole Guadeloupe Créole Martinique Ferrandaise Flamande Originelle Froment du Léon Gasconne Inra 95 Limousin Lourdaise Maraîchine Marine Landaise Mirandaise Montbéliarde Nantaise Normande Parthenaise Pie Rouge des Plaines Raço di Biou or Camargue Rouge des Prés or Maine-Anjou Rouge des Prés Lait Rouge Flamande Salers Salers Lait Saônoise Tarentaise Villard de Lans Vosgienne v t e Lists of French agricultural domestic animal breeds Cattle Chickens Donkeys Goats Horses Pigs Poultry Sheep Retrieved from " https://en.wikipedia.org/w/index.php?title=List_of_French_cattle_breeds&oldid=1208908088 " Categories : Cattle breeds originating in France Lists of French domestic animal breeds Hidden categories: Articles with short description Short description

672-540: The Vendée and the Gâtine, but was under threat, both from the difficulty of finding bulls that met the stringent regulations for registration for artificial insemination , and from reduction of herds by culling to eradicate bovine tuberculosis . By the 1960s it had become clear that the dual-purpose aim for the breed was no longer viable, and in 1971 the decision was taken to select for beef production only. Since that time

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704-448: The allele that codes for the dominant trait . This allele, often called the "dominant allele", is normally represented by the uppercase form of the letter used for the corresponding recessive trait (such as "P" for the dominant allele producing purple flowers in pea plants). When an organism is homozygous-dominant for a particular trait, its genotype is represented by a doubling of the symbol for that trait, such as "PP". An individual that

736-474: The different variations in the genes do not affect the normal functioning of the organism at all. For some genes, one allele may be common, and another allele may be rare. Sometimes, one allele is a disease -causing variation while another allele is healthy. In diploid organisms, one allele is inherited from the male parent and one from the female parent. Zygosity is a description of whether those two alleles have identical or different DNA sequences. In some cases

768-3284: The 💕 This is a list of the cattle breeds considered in France to be wholly or partly of French origin. Some may have complex or obscure histories, so inclusion here does not necessarily imply that a breed is predominantly or exclusively French. The list includes breeds from the overseas territories of France . Indigenous breeds [ edit ] Local name(s) English name, if used Notes Image Abondance [REDACTED] Alpha 16 Armoricaine Armorican [REDACTED] Aubrac [REDACTED] Bazadaise [REDACTED] Béarnaise [REDACTED] Betizu [REDACTED] Bleue de Bazougers Bleue du Nord [REDACTED] Blonde d'Aquitaine [REDACTED] Bordelais (extinct) Bordelaise [REDACTED] Bretonne Pie Noir [REDACTED] Brune French Brown Casta or Aure et Saint-Girons [REDACTED] Charolaise Charolais [REDACTED] Corse [REDACTED] Créole Guadeloupe Créole Martinique Ferrandaise [REDACTED] Flamande Originelle Froment du Léon [REDACTED] Gasconne [REDACTED] Inra 95 Limousine Limousin [REDACTED] Lourdaise [REDACTED] Maraîchine [REDACTED] Marine Landaise [REDACTED] Maine-Anjou – see Rouge des Prés Mirandaise [REDACTED] Montbéliarde [REDACTED] Nantaise [REDACTED] Normande [REDACTED] Parthenaise [REDACTED] Pie Rouge des Plaines [REDACTED] Raço di Biou Camargue [REDACTED] Rouge des Prés or Maine-Anjou [REDACTED] Rouge des Prés Lait Rouge Flamande [REDACTED] Salers [REDACTED] Salers Lait Saônoise [REDACTED] Tarentaise [REDACTED] Villard De Lans [REDACTED] Vosgienne [REDACTED] Imported breeds [ edit ] Aurochs reconstitué Blanc-Bleu or Belgian Blue Brahman Canadienne De Combat Hereford Hérens Jersiaise or Jersey Prim' Holstein or Holstein Simmental Française or Pie Rouge de l'Est References [ edit ] Interrogation de la base bovine (in French). Paris: Bureau des Ressources Génétiques. Accessed May 2015. Breeds reported by France: Cattle Rome: Domestic Animal Diversity Information System of

800-538: The land was turned to pasture . A number of dairy co-operatives were formed, and the Parthenaise was used to produce a local type of butter, the Beurre Charentes-Poitou  [ fr ] , which quickly became well-known. By the late nineteenth century the stock numbered some 1.1 million head. A herd-book was established in 1893 or 1894. From that time the population began to decline. This

832-596: The mh double-muscling gene, while bulls used in Maraîchine breeding were heterozygous or homozygous recessive. The Maraîchine thus represents a traditional form of the Parthenaise. Some cattle have been exported to Belgium, to Ireland, to the Netherlands and to the United Kingdom. The coat ranges in colour from light to dark wheaten, with grey rings round the muzzle and eyes. The skin is black, as are

864-400: The origin(s) of the alleles in a genotype. When the two alleles at a locus originate from a common ancestor by way of nonrandom mating ( inbreeding ), the genotype is said to be autozygous . This is also known as being "identical by descent", or IBD. When the two alleles come from different sources (at least to the extent that the descent can be traced), the genotype is called allozygous . This

896-711: The population has grown consistently: the number of breeding cows rose from 7000 in 1990 to 33 000 in 2008. In 2014 the total breed population was reported at 43 187 . In 2000 it was decided that the criterion for distinguishing the modern Parthenaise from the more traditional Maraîchine – which also descends from the old Vendéenne grouping – would be the bulls used for reproduction: offspring of bulls born later than Joli-Coeur (born in 1974) would be considered Parthenaises, while offspring of older bulls, of which stocks of semen were still held, could be considered Maraîchines. A genetic study in 2004 found Joli-Coeur and all approved Parthenais bulls born after him to be homozygous for

928-459: The same genes are on the Y chromosome . Transgenic mice generated through exogenous DNA microinjection of an embryo's pronucleus are also considered to be hemizygous, because the introduced allele is expected to be incorporated into only one copy of any locus. A transgenic individual can later be bred to homozygosity and maintained as an inbred line to reduce the need to confirm the genotype of each individual. In cultured mammalian cells, such as

960-460: The term "zygosity" is used in the context of a single chromosome. The words homozygous , heterozygous , and hemizygous are used to describe the genotype of a diploid organism at a single locus on the DNA. Homozygous describes a genotype consisting of two identical alleles at a given locus, heterozygous describes a genotype consisting of two different alleles at a locus, hemizygous describes

992-886: The western part of France, from the Loire to the Gironde . It is closely related to the Maraîchine , the Nantaise and the extinct Marchoise and Berrichonne, all of which belong to the same group. Oxen of this type were used mainly for agricultural draught work in Haut-Poitou  [ fr ] , in the Saintonge , in Touraine and in the Vendée . The cattle were sometimes called Gâtinaises or Boeufs de Gâtine , so named for

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1024-693: Was partly because of the mechanisation of agriculture , which reduced the need for draught cattle, and partly because of competition from specialised breeds which began to reach the area from other parts of France: the Maine-Anjou and later the Charolaise for beef, and the Normande and later the Friesian for milk. After the Second World War the Parthenaise was still well represented in

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