Breeding technique of Beef cattle

There are two breeding techniques for beef cattle, and artificial breeding is one of them. Let's take a look.

Artificial breeding technique of Beef cattle

Instrument liquid nitrogen tank (preferably 3 liters), liquid nitrogen, frozen semen (frozen semen in thin tube is more convenient), semen insemination (tube), thermometer, tweezers, scissors, a 3-meter-long rope. The weight of the above equipment shall not exceed 15 kg.

II. Operation

1. According to the farmers to report the oestrus status of the cows and their own experience to judge, choose the time to bring good equipment to the farmers.

two。 Baoding of the estrus cow. The traditional steer Baoding method is adopted to carry out Baoding, that is, rope Baoding. First tie the estrous cow to a stable pile, then half a 90% discount on a 3-meter-long rope, wrap it around the tie column between the hoof and the overhanging hoof of the cow's hindlimb, and then pull one end of the rope through the middle of the cow's forelegs to the neck. At the same time, pull the other end from the outside of the foreleg to the neck; finally, tie the two ends of the rope in the neck to make the cow's fastened hind legs hang. In addition, hang the cow's tail with a string and wash the cow's vulva with clean water.

3. Semen thawing: first prepare an appropriate amount of 37 ℃ warm water in a container, then use tweezers to take out a thin tube of frozen semen from the liquid nitrogen tank and soak it in warm water, gently shake it out about 10 times, wipe off the water droplets on the surface of the tube, cut off the seal, put the embolized end down into *, put on the coat and tighten.

4. Insemination: insert one hand into the rectum across the intestinal wall to grasp the cervix, while the hand arm presses hard to open the vulva door, and the other hand holds the semen that has been frozen on the thin tube * tilt upward from the vulva door and then insert it downwards, so that the insemination mouth is aligned with the cervical orifice and is inserted all the way to the junction of the cervix and the uterine body, and the insemination can be withdrawn at the same time with the injection. In order to ensure the conception rate, it should be repeated every other day.

5. Postoperative cleaning: first untie the cow; secondly clean (manage) the equipment and pack the package; then go to the station to disinfect the equipment and preserve it for next use. The use of rope Baoding can be used to breed at home and expand the mating surface without affecting the health and conception rate of cows, which is welcomed by farmers.

Free mating mode

In this way, the year-round workers of bulls are put into the herd of cows to mate freely in a certain breeding season. This method is simple and can reduce the mismatch of cows and increase the number of calves. However, the utilization rate of bulls is extremely low, and the mating times can not be controlled, which shortens the useful life of improved bulls; the bloodline of cattle is unclear, and it is easy to have early and near new mating, which affects the quality of cattle; it is easy to spread reproductive diseases and cause outgrowth; breeding and calving dates are out of control; it is not conducive to planned production. Therefore, the disadvantages of free mating far outweigh its advantages and have been gradually replaced by other advanced methods.

Control mating mode

It is a method to artificially control the mating of males and cows. Although it still belongs to the nature of natural mating, it is much better than free mating. Males and cows can mate by artificial selection and under specific conditions.

Identification of estrus in beef cattle

1. External observation

The external performance and mental state of the cow were observed, and the estrus and estrus degree were judged by the sexual excitement and vulvar changes of the cow. It can be divided into three periods according to cow performance.

Early estrus: estrus cows climb over other cows, looking restless and mooing, but are unwilling to accept the climb of other cows, the vulva is slightly swollen, the mucous membrane is pink, transparent mucus flows out of the vulva, and the amount is as thin as water, and the stickiness is weak.

Mid-estrus (peak): the cow quietly accepts the climbing of other cows (called stable hurdle phenomenon). The hindquarters of the estrus can see the trail left by the climb. Transparent liquid flows out of the vulva. The quantity is increased, the stickiness is strong, and it can be pulled into a long strip in the shape of a thick glass rod, which is not easy to break. The vulva is congested with obvious swelling, reduced wrinkles, flushing mucosa and frequent micturition.

Late estrus: at this time, the cow no longer accepts the climbing of other cattle, and the congestion and swelling of the vulva begins to subside, resulting in less mucus and poor stickiness.

2. Vaginal examination

The vagina was opened with an opener to observe the color of the vaginal wall and the changes of mucus and cervix secreted. When in estrus, the cow's vagina is moist, flushed, with more mucus, and the cervix is open and slightly swollen. This method can not accurately judge the degree of oestrus, but it can sometimes be used as a reference for the identification of estrus in cows.

3. Rectal examination

Put your arm into the female's rectum and touch the ovaries and follicles with your fingers across the rectal wall. The person who touches the ovary is small, shape, texture, the location, size and elasticity of the follicle development, the thickness of the follicular wall, whether the follicle is ruptured, whether there is corpus luteum, and so on. In the early stage of estrus, the follicle is 1-1.5 cm in diameter, showing a small ball, some protruding from the surface of the ovary and fluctuating obviously; in the middle of estrus

(high tide) the follicular fluid increases, the follicular wall becomes thinner, tense and elastic, and there is a feeling of breaking at a touch; the follicular fluid flows out in the late estrus, forming a small depression.