What should pig farmers do?

1. Selection of reserve sows: First-born sows have plump breasts, obvious intervals and long milking time, so it is appropriate to tame sows and keep seeds. The postpartum weight of sows decreased obviously, and the weight gained quickly during pregnancy. During lactation, the appetite is strong, and those who are digested and absorbed should stay.

2. Management indicators of sow feeding

(1) reasonable weight during breeding:100-135 kg;

⑵ Age at the time of breeding: 7-8 months old, no more than 10 months old;

⑶ Estrus times during mating: 2-3 times;

(4) Back fat thickness in breeding period: 16- 18mm.

3. Feed the sow in stages.

(1) Feeding management in the early growth and fattening period (30-60kg): feed in the growth and fattening period is adopted, and free intake is allowed;

⑵ Feeding management (60- 100kg) in the late stage of growth and fattening: special feed for sows is adopted, which can be freely eaten. After 100kg, the feeding amount can be increased or decreased according to the specific situation.

4 sow estrus identification:

(1) There is electrostatic reflection on the back; (2) Ears erect, eyes dull and loss of appetite; (3) The vulva is red and swollen, with viscous liquid flowing out. If the performance is to accept the boar climbing, it can be determined as estrus.

5. Sows are not in estrus:

1. Congenital factors: mainly physiological defects and genetic defects, such as imperfect reproductive organs, bisexual pigs, abnormal hormone secretion, etc. In addition, the existence of seasonal reproductive disadvantage genes may also lead to seasonal sows not estrus.

2. Infectious diseases: swine eperythrozoonosis, porcine reproductive and respiratory syndrome, swine pseudorabies, swine brucellosis, Japanese encephalitis, parvovirus, chlamydia and other diseases can all lead to poor reproductive development of pigs, and even lead to non-estrus or inconspicuous estrus of pigs, thus causing reproductive disorders.

3. Poor feeding management: sows are not in estrus, mainly for the following reasons.

① Nutrition: Due to malnutrition, sows are too thin to be in estrus; Feeding a single variety of feed causes malnutrition in sows and leads to estrus. Lack of vitamins and trace elements in the feed of reserve sows or mycotoxins in the feed will cause sows not to estrus. Excessive nutrition will lead to sow fattening, ovarian fat infiltration, follicular epithelial adipocyte degeneration, follicular atrophy or ovarian cyst, and also lead to sow estrus.

② Sows are weaned too late, and the weight loss of sows exceeds 15kg, which leads to poor physique and delayed estrus or no estrus after weaning. 4. Obstetric diseases of sows (such as endometritis) can also cause estrus.

6. sow estrus:

The sow begins to estrus after sexual maturity, and the interval from this estrus to the next estrus is called estrus cycle. The estrous cycle is generally 18-23 days, with an average of 2 1 day, and the duration of each estrus is 3-5 days. The duration of young (reserve) sows is longer than that of adult (multiparous) sows.

The external characteristics of sow estrus are mainly manifested in the changes of behavior and genitals. The estrus cycle includes the following stages:

(1) Preestrus: In the early estrus, sows show anxiety, loss of appetite, vulvar swelling and mucus outflow. At this time, boar climbing is not accepted.

(2) Estrus: As time goes by, the appetite drops obviously, and even people stop eating. There are eight buildings in the circle. They lie down, climb the wall, arch the ground and hurdle from time to time to let boars approach and climb. Put your hand on his hip and stand still. When several sows are in the same column, the sows in estrus climb on other sows. The labia mucosa is purplish red, with thick mucus.

(3) Late estrus: At this time, the sow becomes quiet and likes to lie down, the vulva swelling is reduced, the boar refuses to climb, and the appetite gradually returns to normal.

(4) Interestrus: The sow has no sexual desire and her mental state has completely returned to normal.

7. Collection and dilution of boar sperm:

Equipped with diluent, select medium and long-acting diluent powder and double distilled water to dilute as needed (stir with a glass rod, stir for 5 minutes, stand for 30-60 minutes, and then put it in a constant temperature water tank to preheat the set temperature to about 38 degrees). Turn on the power supply of the microscope constant temperature stage and preheat it to about 38 degrees. In order to keep semen activity for a long time, some sugars such as glucose were added.

Preparation of the sperm collection cup: First, line the thermos cup with a one-time capacity of one liter, then cover the cup mouth with absorbent gauze or filter paper, and fix it with a rubber band. The rubber band should be looser, so that it can sink to about 50px. Put into a constant temperature drying box at 37-39 DEG C for later use.

Drive the boar to the sperm collection column, wash its abdomen and foreskin with 0. 1% KMnO4 solution, squeeze out the foreskin to accumulate urine, then rinse it with clear water and dry it. After the boar climbs the fake pig, the sperm collector holds the sperm collecting cup in one hand and disposable PE gloves in the other (too smooth to fade), straightens the penis into an "S" shape when rushing forward along the boar, and grasps the first and second folds of the penis spiral, so that the penis can stretch naturally when the boar rushes forward without being forced to pull. After full stretching, the penis will stop moving forward, reach a stiff and "locked" state, and start ejaculation.

Boars generally ejaculate in three stages (1-3). In the first stage, a small amount of semen is not collected, and concentrated milky white or gray white semen is collected. In the middle, collect transparent and thin semen and colloidal substances as appropriate (it is beneficial to keep warm in winter) until the boar ejaculates. Pay attention to prevent the liquid or other impurities in the foreskin from entering the sperm collection cup during sperm collection.

Don't let go and don't touch the penis when ejaculating, otherwise the pressure drop will lead to the interruption of ejaculation.

After ejaculation, quickly remove the filter paper, cover the sperm collection cup, and send it to the construction laboratory.

Thoroughly clean the sperm collection column before work.

Frequency of sperm collection: twice a week for adult boars and once a week for young boars (about 1 year). It is best to fix the frequency of sperm collection for each boar, even if it is not necessary to collect sperm every seven days to consolidate its memory and check the semen quality under a microscope.

8. Breeding:

Our factory mainly adopts positioning frame for breeding. When breeding sows in estrus, it is necessary to pay attention to cleaning the vulva of sows with potassium permanganate and drying it with paper towels. And you can't touch the head of the vas deferens directly or indirectly with your hands. The room temperature of vas deferens bottle should be about 65438 06 degrees.

Avoid lying down during and after breeding 10 minutes. Some sows have oestrus and metritis, which leads to breeding failure, so it is necessary to wait until the next oestrus before breeding.