Artificial insemination

insemination The artificial insemination is a biotechnology which was already practiced by the Arab in XIVème century on the mares. It sophisticated at the beginning of the 21st century by veterinary surgeons and scientists, and was begun to be usually used as from the years 1940. It is in the beginning used for the improvement of the bovine races, before seeing its field of application extended to other species, of which the mankind (for which it makes it possible to cure certain cases of infertility). The term is used since 1936 by Lucien Cuénot and Jean Rostand in their book Introduction to the genetics . It is formed by derivation of the Latin inseminare “to sow in, spread in, fertilize”.

Artificial insemination of the woman

Animal insemination

It is practiced nowadays with large scales on very many species the animal ones: bovines, caprine, porcine, ovine, équidés… This method of reproduction meets several aims. Initially genetic improvement of the livestock: indeed thanks to this technique it is possible to fertilize a great number of females with the seed of only one male. As its descendants will inherit part of its genetic inheritance, this male will be selected according to its qualities: muscular development for example for a bull of beef breed. Other reasons are also proposed: economy permitted by the reduction of the population of male reproducers, the limitation of the health hazards (sexually transmitted diseases), or the control of the period of setting-low.

Directions for use

Taking away of sperm . In center of selection, the seed is taken on males selected for their performances. For this purpose one generally uses an artificial vagina and various shows aiming at stimulating the process of ejaculation (mannequin imitating the female for example).
Put in spangles . The seed is diluted in physiological liquid in laboratory before being split in small amounts and cooled or frozen, after being mixed with cryoprotecteurs such as the Glycérol (the capacity of sperm to support congelation is variable according to the species). Each amount is called a spangle. Several stages, of controls are carried out. The batches likely not to be fertile are withdrawn.
Storage and transport. The facility of storage and transport is related to the use of liquid nitrogen bottles.
Use. An inseminator defrosts a spangle before the introduction into the maternal uterus to ensure fecundation.

Advantages

It allows the multiplication . Thus, a diluted éjaculat makes it possible to give a hundred descendants, giving an important diffusion of the best male reproducers and thus an improvement of the performances of a race or species in direction of the required objectives of profitability. In goes up natural bovine, one estimates that a male can fertilize only 30 to 40 cows per annum, against several thousands for its congeneric in center of selection.
It allows the conservation . The seed of a male can be stored during years and transported easily everywhere. This aptitude is used for large scales by the centers of selection. The young males are tested on descent at the same time as their seed is collected and frozen. The tests intended to measure the performances of their offspring can last several years. When a male is considered to be interesting within sight of the tests, it can be already at the end of the lifetime of reproducer. The stock of seed is then welcome to ensure a descent to him. For example to check that a bull of dairy race makes well a improvement in term of dairy potential, it is necessary that a sufficient number of his/her daughters calved and that one could estimate their dairy production. This evaluation requires controls (weighed milk at the time of the draft at different stages from lactation), which one will compare with the performances mothers. A mathematical model will then make it possible to consider the value genetic of the bull compared to the whole of the controlled population: in the jargon of this branch of industry, one calls that the index.
Assistance with the safeguard of races threatened of disappearance . The individuals of races to small manpower are grouped in families and insemination is directed by an defense association. Each family is separate between males and females and the seed is selected in the most distant families genetically. Insemination makes it possible to make travel the seed where the transport of a reproducer would be too expensive. The Norway, rather than to maintain the bovine herds of more than 1 000 individuals, threshold where consanguinity is easier to manage, prefers to store seed. Thus, with each generation, the seed of the young males corresponding best to the standard of race is stored. Contrary, seed of bulls died since 20 or 30 years is reinjected to bring new blood.
Facilitated use. A stockbreeder can choose on catalog the male which it will couple with the female of his breeding. Thus, it does not need to nourish a male at the year and can choose various parents for each one of its boarders.
Fight against the diseases . The shortly after the second world war, epidemics of Foot-and-mouth disease and bovine Tuberculose make devastations. The insulation recommended by the veterinary surgeons is easier to control with insemination: it makes it possible to fertilize the cows without displacement nor direct physical contacts between male and females of different herds.

Criticisms

This practice is criticized by personalities of the animal cause as Jacqueline Bousquet which directed Pro-animated. According to it, this practice generates animal suffering and in the long term a weakening of the animal species.
fecundation is not sure to 100%. One second attempt generates an additional cost. In the breedings where the " monte" is natural, the stockbreeder does not worry about the coupling. It takes place several times until fecundation has place.
This practice contributed to the strong reduction in diversity inside certain animal species, by facilitating the massive diffusion of the most productive races. The crossing of absorption thus makes it possible to change bovine race on a herd scale into some generations. Thus the use of seeds of very productive races on the old races gradually made them disappear.
during fast genetic improvement of the livestock permitted by artificial insemination (male way) is the increase in consanguinity in the population: some male individuals monopolize most of genes of the population and the degree of relationship between individuals increases unrelentingly. The risk to see appearing tares increases. Certain characters which undergo a strong pressure of selection can involve negative consequences on other characters: one speaks then about antagonistic natures. By selecting their animals according to the character " speed of traite" for example, the stockbreeders of milch cows increased the risks of infections of the udder (Mammite), risk directly related to the conformation of the sphincter responsible for the ejection of milk.
a possible drift is the existence of races which cannot reproduce any more naturally. The chickens raised out of battery grow so much quickly that their fragile skeleton yields under their weight. To obtain reproducers of these races, it is necessary to underfeed the individuals to make it possible their skeleton to grow at the same speed as their muscular mass. At the bovines, the race Blanc Belgian blue was selected on individuals with the hypertrophied muscular mass. The legs before males pain to carry such a mass. Goes up natural is not more possible. In addition, the cows must often calve by Cesarean because of the size of calves.

To proceed to an insemination

Artificial insemination uses frozen sperm.

“The use of artificial insemination will contribute to the reconstitution of the herds” (WOLKOWITSCH, Élev., 1966, p. 81).

“The dairy races (...) were the first to use artificial insemination at ends of genetic improvement” (Breeding, insemination, No spéc. Statistics, 1978, p. 36).

See too

External bonds

Artificial insemination and bovine dairy production: effects of a biotechnology on a die of production, by J. MALLARD and J-C. MOCQUOT, 1998, INRA Animle Production, N° 11, pages 33-39.
Definition on TLFI

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Artificial insemination