Methods and techniques of artificial insemination of cows, instruments and analyzes
Insemination is the introduction of bovine semen into the bovine reproductive tract for conception. Cattle are fertilized by natural mating and artificial insemination, and the second method is more in demand in large livestock farms, since it is effective and does not require much time. An inseminator is engaged in artificial insemination of cows - a qualified worker who must know the rules for handling animals and the intricacies of a safe procedure.
Content
- 1 Pros and cons
- 2 When and how many times should artificial insemination be performed?
- 3 Preparation for the process
- 4 What tools and materials will be needed
- 5 Bull selection
- 6 How to identify a cow that is ready to inseminate?
- 7 Insemination techniques and techniques
- 8 Further care of the animal
- 9 Signs of successful insemination
- 10 Possible errors and difficulties
Pros and cons
Artificial insemination is a convenient and popular method of cattle fertilization.
When and how many times should artificial insemination be performed?
For successful artificial insemination, it is important to guess the optimal time for germ cell fusion. For this, several nuances are taken into account:
- The cow's ovum is ready for fusion with the sperm for no longer than 10 hours. After this time, the aged cell becomes non-contact, and if fusion occurs, then the risk of pathological development of the embryo increases. Therefore, semen must enter the cow's reproductive tract before ovulation.
- The sperm must break through the egg membrane. This takes 4-6 hours before ovulation.
- Bovine sperm with natural fertilization live for 2 days, with artificial - a day. Therefore, it is necessary to prepare the seed for the procedure a day before ovulation.
The optimal time for artificial insemination is 3-4 in the morning. At this hour, ovulation is inhibited, corresponding to the days from the end of the rut. If hunting is in the morning, then insemination should be in the evening - at 18-19 hours.
Sperm is injected before milking or at least 2 hours after it.Before 2 hours it is impossible: the cow's brain sends a signal that makes the uterus block the acceptance of sperm.
Preparation for the process
The first step is to clean the room. It is necessary to use preparations without aggressive chemical components as disinfectants. The stall should be cleaned of manure and dirty bedding, rinsed with water from a hose under pressure.
The veterinarian should examine the cow, make an analysis for the absence of infection. The area of the tail, vulva, anus, inner thighs is washed with warm soapy water and wiped with a clean cloth. If rectocervical insemination is planned, then a rectal examination is performed for the absence of inflammatory foci, and feces are removed from the rectum. The vagina is treated with an antiseptic solution "Furacilin".
Tools are disinfected with drugs or fire. The inseminator, having washed his hands with soap, puts on sterile rubber gloves, lubricates them with medical alcohol, then petroleum jelly.
What tools and materials will be needed
Artificial insemination is carried out in a separate room with an arena, a section for preparing a cow, and a laboratory section.
Room device and equipment:
- the arena is equipped with machines that fix the cow for the safety of manipulation;
- the laboratory department contains a catheter, a syringe, containers with biomaterial, a microscope;
- in the preparatory department there is a washing, disinfectants, work clothes.
Bull selection
Both with natural mating and with artificial insemination, bulls are more important for the formation of the breed qualities of future offspring than cows. In a year, one inseminator becomes the parent of several hundred calves.
The main indicator of bull selection is pedigree. The pedigree qualities of the manufacturer are assessed for three generations. A good bull should be the offspring of females with high milk production and milk fat content, and males with productivity genes. The second indicator is the constitution and body weight of cattle. A bull suitable for insemination is distinguished by its developed muscle mass, strong and fleshy hind legs, large reproductive organs. You should also take into account the quality of the sperm, the percentage of viable sperm.
How to identify a cow that is ready to inseminate?
A cow that has entered a sexual hunt changes behavior:
- worries, shows aggression;
- rushes around the corral, pasture;
- eating poorly;
- breathes frequently;
- shows interest in individuals of the opposite sex;
- puts his head on the back of other animals;
- tries to lick the genital area of other heifers;
- well-being is affected by an increase in heart rate and an increase in body temperature;
- milk yield decreases.
The cow's hormonal cycle resumes after 18-24 days. The cycle is divided into 3 phases: excitement, relaxation, balance. The first phase is the time for the maturation of the egg. Estrogens are released into the bloodstream, heat begins. Hunting lasts 10-20 hours. During this period, the vulva swells and turns red, first a clear liquid flows out of the vagina, then a viscous and viscous mucus, sometimes with blood streaks. The cervix opens slightly, its muscles relax.
To determine the cow in the hunt, a probe bull is launched into the herd. The method is optimal for a large population. The probe is a sexually mature male in which the seminal canals are surgically clamped. In a herd of 100 females, it is enough to run one bull. A coloring mark is attached to the male's neck. Cows whose backs turned out to be painted after a walk with a bull are in the hunt.
There is a phenomenon of false hunting, when a cow is worried, interested in males outside of ovulation. The reasons for this phenomenon are different, but more often it is associated with the formation of cysts in the genitals.
In large farms, other methods of determining the hunting of a cow are also practiced:
- measurement of vaginal and rectal temperature;
- examination of the crystallization of cervical mucus under a microscope;
- analysis of the activity and behavior of the cow;
- measurement of electrical resistance of vaginal tissues (it significantly decreases during ovulation due to increased humidity).
Insemination techniques and techniques
There are 4 methods of artificial insemination of a cow. In each case, the introduction of seminal fluid into the uterus is meant, the differences are only in the technique of administration. The semen should have a temperature of 36-38 ° C.
| Insemination method | Tools and materials | Execution technique | Notes |
| visocervical | 4 containers with tight lids (1 - with sodium chloride solution, 2 - with 70% alcohol, 3 and 4 - with sodium chloride), catheter, illuminated mirror, container for waste liquids | the instruments are alternately treated with 4 solutions, a warm mirror is inserted into the cervix, a 4 cm catheter is inserted into the cervix, sperm is injected, the catheter is removed, then the mirror | the operator performing the procedure must be qualified, as there is a high probability of injury to the neck |
| rectocervical | catheter, long veterinary insemination gloves | a hand in a glove is immersed in the anus of a cow, the genitals are groped, the catheter is inserted into the genital tract with the other hand, the hand in the rectum is wrapped around the neck, the tip of the catheter is felt, the instrument is pushed deeper into the neck by 5-8 cm, sperm is injected, the catheter is taken out | fertilization will be successful only in the case of a relaxed state of the cervical walls, otherwise the sperm will not be able to penetrate into the uterus, and rectocervical insemination may result in injury |
| manocervical | catheter, sterile semen ampoule, veterinary gloves | a gloved hand is immersed in the genital tract, the vagina is massaged for about 2 minutes, a catheter with sperm is inserted into the cervix, advanced 6-8 cm, sperm is poured into the relaxed uterus, re-massaged to receive sperm by the uterus, the hand is carefully removed from the vagina | the method is not applicable at home, the cow is taken to the insemination station, the vaginal method of sperm injection is not for beginners, the inseminator must be trained, know the anatomy of the genitourinary system of cattle, the technique is not suitable for insemination of young females with a narrow vagina |
| epicervical | catheter, veterinary glove | a gloved hand is immersed in the anus, the uterus is massaged through the colon, a catheter is inserted, the sperm is poured into the vagina closer to the cervix, the catheter is taken out, the clitoris is massaged to receive sperm by the uterus | the method is used for insemination of females who have not given birth before, as well as individuals with small body dimensions |
Further care of the animal
For artificial insemination to be successful, after the procedure, the cow is provided with peace and quiet. A separate clean stall is prepared for her, the daily portion of feed is increased.
For half a month, the animal is under close supervision. If there is no deterioration in health, then the cow is combined with the rest of the herd.
Signs of successful insemination
Successful artificial insemination is determined in the following ways:
- rectal or vaginal examination;
- by changing the behavior of the cow - after about 10 days, she begins to avoid bulls;
- in the absence of another heat;
- according to a blood test on days 20-23 after insemination, an increase in the concentration of progesterone indicates a pregnancy.
A cow carries a calf, like a woman - 9 months.The external signs of pregnancy become noticeable after about a month. If insemination was unsuccessful, then a new sexual heat begins. In this situation, repeated artificial insemination is performed. A total of 4 attempts are made, if all are unsuccessful, then the cow is diagnosed with "functional disorder of the reproductive organs."
Possible errors and difficulties
Inexperienced inseminators often make gross mistakes, due to which artificial insemination is ineffective, and the cow gets injured or injures the worker. The main mistakes and difficulties arising from artificial insemination of cattle:
- Non-compliance with hygiene rules and unsanitary conditions. Use of unsterilized instruments, which leads to infection of animals.
- Ignoring the need to examine the cow for readiness for fertilization and the absence of inflammation.
- Accidental touching of the catheter with gloves lubricated with petroleum jelly. Vaseline acts as a spermicide, destroys sperm cells, resulting in no fertilization.
- Incorrect temperature storage conditions for semen. It must be stored in liquid nitrogen.
- The use of an obliquely cut ampoule, due to which sperm flows not into the cervix, but into a syringe.
- Incorrect advancement of the catheter, getting it into the urethra. The correct direction of the catheter is 30 °.
- Too deep immersion of the catheter, fraught with injury to the uterine walls.
- The sperm is squeezed out not into the neck, but into the blind pocket surrounding it.
- Rough treatment of a cow. The animal either goes into a rage, injures the abuser, or does not become pregnant due to the stress it has endured.
To avoid the above problems, farmers should hire inseminators with experience, qualifications, excellent knowledge of cattle anatomy and a high reputation. Also, the specialist is required to be able to accurately identify the period of sexual heat in a cow.
