Basic rules for artificial insemination of cows

Artificial insemination of cows is one of the most common breeding methods. This method allows you to get a healthy offspring, with accuracy to calculate the term of labor. This technique has a great advantage over natural fertilization.

Artificial insemination of cows

How to choose the right time

H In order to carry out artificial insemination of cows, it is necessary to choose the most optimal period for the egg to meet with the sperm. In order to determine the term correctly, it is necessary to be guided by three factors.

1. It is important to remember that the susceptibility to fertilization in a mature egg is the only 5-10 hours. After this time, it ages and increases the risk of improper development of the embryo or its death. Accordingly, by the time of ovulation, the seed should already be in the genital tract.
2. Before fertilization, the sperm goes through the preparatory phase – capacitation. This process takes 5-6 hours.
3. After natural fertilization, sperm can retain their properties while in the tubes for 24-48 hours.The survivability of sperm frozen-thawed is much less and is approximately 12 hours, therefore sperm must be introduced 12 hours before hypothetical ovulation.

All these three positions characterize the importance of accurately determining the timing of ovulation in heifers and seasoned cows . In cattle females, the stage of ovulation occurs during the inhibition period, that is, it occurs at the end of the hunt, after 10-12 hours. It follows that if estrus started in the morning, then artificial insemination begins in the evening, at about 17-19 hours, if estrus was recorded in the evening, then fertilization is carried out in the morning.

Carry out artificial insemination at dairy cows are required 2 hours before milking or 2 hours after. During milking, the brain sends a signal, and the uterine neck does not work on absorption, which significantly impairs the effectiveness of the insemination process. The second important rule determining the success of an event is multiplicity. Females are inseminated, starting from 2 times. First, the procedure is carried out after detecting signs of sexual hunting, the second after 10-12 hours, and if the hunt continues, then every 12 hours.

How to determine sexual hunting

The most accurate sign by which the onset of sexual hunting can be determined is estrus and arousal. At the moment, there are several ways to determine the readiness of the female body for mating. The first way is visual.Animals become restless, look for a male, a white-transparent liquid oozes from the labia, which at the end of the hunt becomes thicker and whiter. The disadvantage of this method is that the listed symptoms cannot be noted in animals with “silent” hunting and in females with diseased limbs.

The second way of determination is reflexological. For this method, a probe bull is used, that is, they watch how the female will react to the presence of the male. A cow in a pore allows the bull to jump onto itself. The method is quite inaccurate, since the probe is led to the attached females, and often the shelter of the body meekly accepts the bull, and young heifers reject it even during the hunt.

The third method is vaginal. Examination of the vagina with a mirror. During the hunt, the mucous membrane will be swollen and reddened, and the fallopian tube is slightly ajar. Transparent mucus oozes from the fallopian tube, which accumulates in large quantities at the bottom of the vagina, then pours out through the external reproductive organs. The disadvantage of this method is the need to bind the animal, often in young females, the opening of the uterine neck is rather weak.

The rectal method involves examining the ovaries through the rectum. At the beginning of the hunt, the mature follicle is well felt, with pressure, fluid movement is felt. The immature follicle will be a solid tubercle, slightly protruding above the ovary.Of the drawbacks of the method, the need for frequent examinations is noted, which can lead to damage to the follicle and the ovum leaving it. The hormonal method involves the determination of the amount of progesterone in plasma, milk or urine. Ultrasound is the most accurate method. The disadvantage is expensive equipment.

What is needed for insemination

Insemination requires not only certain skills and knowledge, but also the availability of equipment. Tools must be prepared and disinfected in advance. The list of instruments that the insemination point should be equipped with:

• thermostat;
• catheter;
• microscope;
• gloves;
• mirror;
• bag in which insemination tools are stored Instructions for the insemination technician.

In addition to all this, you need to carry a large amount various reagents for determining the viability of seminal fluid. You will also need a considerable number of disinfectants. The point where the cows are inseminated must be equipped with powerful lighting devices. Fully equipped laboratories for insemination are available only on the territory of breeding farms, in other cases, the technician works at home.

How to prepare a female for insemination

If insemination is carried out at home, carefully clean the stall. It is important to remember that in no case should you use harsh chemicals for cleaning. To disinfect the room, you can use potassium permanganate. The anus is manually cleaned of dirt, after which the technician finds the uterine opening and makes a massage.

In the next step, the entire back is washed with warm water and baby soap. After washing, the washed areas are treated with furacilin. At the end of all these manipulations, you can proceed directly to insemination. You can watch a detailed video on preparing a female for artificial insemination.

How to cover a cow

Artificial insemination of cows requires knowledge of the structure of the urogenital system in cattle. All insemination methods are based on three determining factors. Instructions for artificial insemination of cows are important information that every farmer should have.

1. It is important to remember that in individuals with a vaginal type of insemination, the cervix absorbs the seed after fertilization and also acts as an intermediate reservoir. Sperm from the cervix come in separate portions to the uterine cavity, respectively, in a single dose for insemination of cows should be at least 10 million sperm.
2. During the natural process, a larger quantity of sperm enters the uterine cavity than during in vitro fertilization. It turns out that the entire dose should be administered directly into the uterine opening.
3. After the birth, the walls of the uterus stretch in the cows, which requires some experience and accurate knowledge of the location of the cervix.

Insemination

The above provisions determine the presence of several techniques for artificial insemination of cows. The first method is epicervical. It is based on the introduction of the seed as close to the uterine neck as possible. This method is used only for heifers. The probability of using this technique is due to the absence of stretch marks on the uterine walls. The female is fixed and a catheter with an ampoule at the end into the vagina is inserted, after emptying the ampoule, it is worth ensuring animal peace.

The manocervical method involves artificial insemination in the uterine canal by manually controlling the location of the uterine opening. One limb is inserted into the vagina and a uterine massage is started, after which the catheter with the ampoule is taken with the other hand and, controlling the hole with the index finger of the hand, push it all the way. The seed is squeezed out of the ampoule and, taking out the hand, massage the clitoris to stimulate the suction process. The technique of artificial insemination of cows by any method requires special attention to this process, since massage movements in the clitoris area stimulate not only absorption, but also ovulation.

The visocervical method is fertilization with visual inspection of the uterine opening. Technique of the method: female fixation, insertion of a gynecological mirror into the vagina, insertion of a catheter with an ampoule. If it is necessary to artificially inseminate several females at once with the sperm of one bull, it is necessary to thoroughly disinfect the catheter after each animal. The disadvantage of this method is the risk of damage to the walls of the vagina by the mirror.

Rectocervical method – the process of introducing sperm into the vagina with the control of the uterine opening through the rectum. Fertilization in this way is considered the most suitable option. Rectocervical method provides a one-time control of the fallopian tube, the exact introduction of seminal fluid and massage the clitoris. Technique: fixation, advancement of the catheter all the way into the cervix, palpation and fixation of the cervix, fluid injection.

How to find out if the insemination was successful

After artificial insemination it’s less important to correctly determine the success of an event. To date, the most common and accurate methods for determining pregnancy are:

• rectocervical;
• hormonal;
• Ultrasound.

When using the first method during examination, one uterine horn will be clearly larger than another with a loose consistency. The ovary, related to the horn of the fetus, is much larger than the second, the corpus luteum is clearly palpable in it.The fallopian tube is closer to the pelvic entrance. The hormonal method is based on determining the level of progesterone to blood, urine or milk. It is mainly carried out in the laboratory. From the beginning of ovulation, a yellow body is formed in cattle that synthesizes the hormone. When pregnancy occurs, this gland does not degenerate, but develops. The highest concentration of the hormone in the blood is observed at 4 weeks of gestation, after which the level drops slightly.

One of the drawbacks of the method for determining the amount of hormone in the plasma is the significant variability in the fluctuations in the level of progesterone in the blood of different individuals. In addition, a similar picture can be observed with persistence of the corpus luteum. Ultrasound is considered the best method for determining the presence of pregnancy or its absence. The method allows you to see the embryo already for 21 days. It is on this day that one can clearly see the heartbeat of the embryo. The disadvantage of the study is the possibility of its use only in the early stages. It is used only up to 3 months of pregnancy, because later the embryo descends into the peritoneal cavity and leaves the working area of ​​the sensors. The second drawback: the rather high price of equipment.

Why the natural method of reproduction is rarely used among livestock breeders

Artificial insemination of cattle was used in ancient times. For this, soft sponges were used that were placed in the vagina of the female before mating.Herders tried, therefore, to inseminate several cows from one bull at once, but the sperm obtained by the barbaric method turned out to be mostly inactive, therefore successful fertilization could be observed only in 40% of cases.

In the future, with the appearance of a large number of diseases Sexually transmitted cattle, people began to improve methods of artificial insemination of cows. Today, natural fertilization is used extremely rarely. Each sperm dose received from a proven inseminator ensures healthy offspring. You can also watch a detailed video clip that will tell you step by step about how to prepare and disinfect tools, as well as what is artificial insemination.