78.Technical equipment of experiments on artificial insemination

In recent years, the widespread promotion and application swine artificial insemination technology in the development of pig production, to carry out the insemination technique not only can reduce the the pigs spread of disease, they can reduce the cost of feeding improve the utilization boars, solve breeding individual differences to increase farming efficiency. Therefore, more and more attention of the pig farmers, France Europe (China) Co., Ltd. – artificial insemination equipment experts engaged in the clinical promotion swine artificial insemination technology for many years, and have accumulated some experience in practical work, and are presented as follows for peer reference .

1, semen quality choice

Select genetic stable performance, the absence of disease, quality athletic boar provenances the boars aged 1 to 4 years old or less, given nutritious feed before semen collection, an appropriate increase in exercise, exercise every day for at least 15 – week 20 rain, and effectively improve the survival rate of boar sperm, semen 2 (regular semen, boar keep good habits), timely laboratory diluted semen collection processing, storage at room temperature.

2, estrus sows identified

Oestrus identification is essential, the key to ensure that sows ability to conceive, the best breeding age and weight of gilts: Usually within 8 months of age, body weight in a 7O 6o kg, the first few of puberty, although the sow the obvious characteristics of estrus, but premature breeding will affect reproductive performance and shorten the useful life, the best is to select the first 4-6 diestrus breeding. Once a the sow appeared tweet, eyes dull hesitant reaction, loss of appetite, intromission behavior press pressure their waist, standing immobile, genital mucus hanging wire, then you can Insemination. Sows, generally in estrus 3 days the vulva swelling subsided slightly (vulva adhesion grass clippings) Insemination, each insemination amount of 15 to 20 mL, for insurance purposes, and generally lose 2 fine, that is the day once in the morning and afternoon times or 1 time in the afternoon, the next morning.

3, the preparation before the insemination

3.1 Strengthen management, breeding a week before, to sow nutritious feed promote multiple ovulation, lined up the eggs, to create conditions for sows conceive.

3.2 equipment ready a length of 40 cln, diameter 9 Inm rubber tube (one end blunt), a 20 ~ 50 mL disposable syringes, medical rubber gloves, 1 double, l0-20 mL inspection boar semen 2% potassium permanganate solution 500 mL.

4 Insemination

Sows vulva with soap and water and rinse, and then 1.5% 2.0% potassium permanganate solution cleaning. Insemination of hands to bring the sterile rubber gloves, vas deferens to the high-temperature sterilization, and to maintain a certain temperature (preferably close to sow body temperature). Insemination in sows the hindquarters with left foot pressed against the back of the sow, the left hand turn a sow pussy, holding his right hand the vas deferens slowly inserted into the vagina, when vas deferens insertion 2h5 ~ 30 cm, will be equipped with semen syringe access to the vas deferens, intermittent promote the syringe piston, slowly semen injection sow the cervix ,1-2min after. Slowly up the vas deferens toward sows root of the tail drawn repeatedly press the pressure sow back several times, Insemination on this end.

Swine artificial insemination techniques suitable for scattered sow breeders, technical requirements, easy to operate, usually as long as observe, accurately grasp the identification of oestrus timely insemination, will be able to receive good results.

79 icrosurgery techniques for embryonic cells (morula, blastocyst), leading to creation of allophenic animals One promising area in the early embryo micromanipulation is the artificial production of chimeras, or genetiТ osaics. The concept of a chimera (grech.Chimaira) is a composite animal. The essence of a biotechnological method of obtaining the chimeras is an artificial combination with microsurgical manipulation of embryonic cells of two (or more) of animals of different breeds and even species. Thus, animals - chimeras are one body features two embryos differing different genotypes (Fig. 9.10). It is believed that a successful embryo transfer can be carried out only between females of one species. Transfer of embryos, for example, sheep and goats to the contrary, accompanied by their engraftment but terminates the birth of offspring. In all cases, the immediate cause of interspecific pregnancy abortion is a violation of the function of the placenta due to maternal immunological response to foreign antigens of the fetus. This incompatibility can be overcome produce chimeric embryos by microsurgery using the following methods: The first method is to obtain chimeras based on combining blastomeres from embryos of the same species. For this purpose, the chimeric embryos obtained complex sheep combining 2 -, 4 -, 8-cell embryos. Each embryo is a complex joint comprised of an equal number of blastomeres of embryos 2-8 parents. Transplant the inner cell mass of each donor (blastomeres) by injection into blastocysts transferred recipients. The total number of cells varied from four to eight times larger than number of normal cells. The embryos were injected into the oviducts of sheep ligature tied to development to the blastocyst stage. Normally developing blastocysts were transplanted to recipients and get live lambs, most of which were chimeric, according to the analysis of blood and external features. A second method to obtain chimeras based on cell mass fusion of two or more embryos in a zona pellucida. This method can obtain aggregation chimeras. The method consists in the fact that the 8-cell embryos were incubated in a medium with a proteolytic enzyme digesting shell egg. Freed from the shells of embryos in contact with each other, resulting in their cells fuse and mixed. Artificial obtaining chimeras began in the mid 70's. In animal known as man-made chimera intraspecific and interspecific. In Germany, the obtained aggregation chimeric animals after joining the halves of 5-6 day old embryos from donor cows and Schwyz Holstein cattle. Of the seven calves produced in five there was no evidence of chimerism, and the two combined in a phenotype characteristic suit two source rocks - brown and black-and-white. The features observed in the preparation of inter-specific hybrids. Interspecific chimeras - embryos after embryo transfer prizhivlyayutsya only 10% of cases. An example of obtaining interspecific chimeras in livestock are ovtsekozy, combining features of the sheep and goats. The authors note that the chimeric animals do not transmit to posterity their characteristic genetic mosaicism. Like heterozygous or hybrid animals in the offspring is split, resulting in a broken valuable genetic combinations.