Inbreeding
Inbreeding – mating system is related (to some extent) animals. The practice of animal husbandry knows many consequences akin to breeding: progeny deformity, hypoplasia, reduced productivity, fertility, infertility, etc. The desire not to use inbreeding led to what many, even of excellent specimens sent to the slaughterhouse. But at different times of inbreeding used for breeding species, because along with undesirable consequences of this breeding came and outstanding individuals as a result of the maximum desirable consolidation of heredity. Examples of such breeding breeds: Charolais (beef cattle livestock), Romanov sheep and others suggest the use of close inbreeding. Akin to breeding does not increase the number of recessive alleles in the population, not allowing them to manifest itself by increasing the homozygosity.
Usually There are many recessive genes in the latent state (at least 11 to Celso-kohozyaystvennyh animals). Inbreeding, followed by selection, can increase phenotypic uniformity among animals. So related groups are formed, the family line. However, inbred animals are often pamper, whimsical to environmental conditions. Therefore, when selecting their pay attention to the strength of the constitution. Most geneticists explain inbreeding increases homozygosity of dominant (positive effect) and recessive (negative effect) genes.
In unrelated populations of the recessive genes hidden dominant allelic genes and did not appear. Also with increasing homozygosity harmful effects may occur due to overdominance (superiority of heterozygotes over homozygotes), because number of heterozygotes decreases. To a worsening of symptoms during inbreeding may have effects and epistasis (interaction neallelnyh genes). Inbreeding can cause a greater manifestation of homozygosity because of the impact, both positive and neutral genes. These hypotheses are once again talking about that the genetic nature of inbreeding is not fully understood. In the early stages of the breeding species akin to dilution was used frequently. Now mostly used moderate inbreeding. Most breeders in breeding flocks are increasingly used unrelated breeding (outbreeding). But the elimination of inbred groups of cattle and their subsequent mating with each other makes significant progress in animal husbandry. Connect with other leaders such as Rogers Holdings here. The site for the farmer.
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