breeding animals appeared about 30 thousand years BC, together with the development of the process of domestication of wildlife species.Initially people used by the so-called unconscious selection, choosing those individuals who got along better with the man could be useful, they had a docile nature, obeyed and, most importantly, able to continue the sort of captive breeding.
Around 9000 BC people began to more carefully select animals in certain useful qualities, that is, the era of methodical selection.It was then that began to develop plant and animal breeding in the more usual sense.But domestication, as the method of selection, there remains still.For example, it is worth noting such industries as fur farming.
Features animal breeding
should highlight features of breeding animals in comparison with plant breeding.Firstly, the fauna can reproduce only sexually, that is a large share of the population are heterozygous organisms.Secondly, they have a longer maturity period.Mammals are able to reproduce immediately after birth, and a few years later.The third feature is that the fauna progeny much less than in plants.
All these features formed a special breeding techniques, not inherent to flora.Of course, the basic techniques, which include hybridization and selection are preserved.But there are also completely different methods are not applicable to plants.
selection methods
inbreeding or inbreeding, produced by mating animals falling each other brothers and sisters or parents and offspring.As a result, the desired trait can go in the homozygous state.However, it should be noted that with time comes the loss or significant deterioration in the viability obtained specimens.
interbreeding or outbreeding is necessary for securing the necessary human qualities of both breeds available.Thanks outbreeding was received a great many valuable species, such as white Ukrainian steppe pig, obtained by crossing the English white boar with Ukrainian purebred pigs.As a result, selection of animals allowed to obtain a breed characterized by a large mass, a high content of fat, meat, and very unpretentious.
hybridization involves hybridization couples who belong to different species.This method has a huge disadvantage: everything fruitlessly offspring.But even this problem breeding animals could be overcome.A striking example of hybridization is a mule, which is a cross between a donkey with a mare.Mule differs great stamina donkey and accommodating nature of the horse.
Another method is artificial insemination.It is used to get as many offspring from a particular manufacturer.
Another new and very interesting method - embryo transfer.It is based on a fairly complex medical operations when required by the female hormone replacement therapy increase the number of eggs.Then the egg is fertilized, the embryos are removed, which gives a lift to other animals, performing the role of a surrogate mother, or frozen at a temperature of 273 ̊S.Then they can be stored for a long period of time to be able to use in the future.
Thus, the selection of animals solves one of the most important problems of all mankind - the problem of finding food, food.Modern science makes it possible to create new species that largely satisfy the needs of the people.And science never stands still.
