Establishment of reasonable parity structure of sows

(agricultural Wealth net) the ideal parity structure of sows is as follows: 20% of the first sows, 18% of the second, 17% of the third, 15% of the fourth, 14% of the fifth, 10% of the sixth and 6% of the seventh. Early pregnancy examination, find empty sows as soon as possible, promote their estrus, and use pregnancy diagnostic instrument in time. After breeding, the pregnancy of sows was determined by B-ultrasonic detector in order to find out the non-pregnant sows and reproduce them in time. This is an effective measure to increase the reproduction rate of sows and reduce the loss of feeding costs caused by empty sows. It is generally determined 25 ~ 30 days after mating. Careful examination of estrus and return to estrus is first of all oestrus, no matter natural mating or artificial insemination, timely mating is an important factor to obtain good fecundity, and accurate investigation is the premise of timely mating. Secondly, find the sows who return to love in time. If there is no pregnancy diagnostic instrument in the field, the oestrus sows can only be detected by manual examination. Therefore, the examination of return should be strengthened in 18 ~ 24 days, 39 ~ 45 days and 60 ~ 66 days after mating. Check the situation with mature boars, twice a day, 30 minutes after feeding in the morning and once before leaving work in the afternoon. The ideal boar should be at least 12 months old, with slow movement and foamy mouth. When driving a pig, use a pig board or another person to limit the speed of the boar. Driving the boar into the sow pen can provide the best stimulation to the sow. By sniffing the sow, on the one hand, the boar can stimulate the sow to estrus, on the other hand, it can also find out the estrus sow. Boars and sows should be contacted twice a day for 20 minutes each time. When the boar arrives in front of the sow, the worker should carefully examine the reaction of the sow behind. It can be checked by pressing the back, and it can also stimulate the ribs and abdomen. The average estrus cycle of sows is 21 days (18 ~ 23 days), and the duration of estrus is 2 ~ 3 days. A sexual cycle is roughly divided into four stages: proestrus, estrus, metestrus and diestrus. The key to successful mating is to correctly grasp the estrus symptoms and timely mating. Proestrus symptoms of sows: vaginal cherry red, swollen, bites, restless, loss of appetite, crawling across, mucus flowing out of the vulva, crawled by sows in the same column, but no static reflex; symptoms of sows during estrus: vaginal redness and swelling, mucus, bow back, dull eyes, ears erect, static reflex, obvious static reflex in the presence of boars Standing still when climbing or being climbed over other sows, loss of appetite, characteristic purring, willingness to accept breeders, and allowing boars to mate. All or some of the symptoms can be observed during estrus, but there are differences between strains. The shorter the interval between weaning and mating, the longer the duration of estrus and the more obvious the symptoms of estrus. When raised in groups, estrus sows will climb over other sows or let other sows climb. When fed in a limited feeding pen, some estrus sows will stand, while others will lie down, so normal estrus symptoms cannot be observed. therefore, the breeder is required to check the estrus with the help of boar head-to-head contact. Reduce the number of non-production days of sows: that is, the number of days of non-pregnancy and non-lactation of sows in the breeding herd. According to the data of the United States, the non-production days of the best pig farms can reach 30 ~ 35 days, and the better pig farms can reach 40 ~ 45 days, with an average of about 70 days, and many pig herds can last more than 70 days. Then, if the gestation period is 114 days and the lactation period is 21 days, the average annual production of each sow in the pig farm with 30 ~ 35 days of non-production days is 2.48 ~ 2.44 litters, the average annual production of each sow in the pig farms with 40 ~ 45 days of non-production days is 2.41 ~ 2.37 litters, and that of the pig farms with 70 days of non-production days is 2.19 litters per year. We use the following example to illustrate the impact of non-production days on the efficiency of pig farms. Assuming that there are two pig farms (A farm and B farm) with 500 adult sows each, the non-production days in A farm and B farm are 40 days and 70 days respectively, and the pregnancy and lactation periods in both AB farms are 114d and 21 days, respectively. The average annual litter size of each sow in AB farm is 2.41and 2.19days respectively. If the litter was weaned 9.5heads, the yield difference was 2.41Mel 2.19litter × 9.5x500sows = 1045 weaned pigs. Assuming that the feed and drug cost of each pig is 1000 yuan, the market price of wool pig is 12 yuan per kilogram, and the mortality rate of medium and large pigs is 10%, then the profit difference between the two AB farms is 1045 × 90 × 100kg × 12 yuan-1045 × 90 × 800 yuan = 376200 yuan. On the other hand, the difference in the number of non-production days between the two pig farms is 15000 days, which means that farm B has raised 41 more unprofitable sows than farm A. If you calculate this item, then the profit difference between the two markets is even higher! If we take the initiative to phase out the pig farms with normal turnover in time, the annual renewal rate of breeding pigs is about 30% to 40%. Therefore, we should take the initiative to eliminate those sows whose parity is too large, performance decline, non-estrus for a long time, inflammation of reproductive organs, poor limbs and legs. Once the elimination of sows is determined, it should be eliminated immediately. It is actually unscientific for some pig farms to be unwilling to eliminate sows when the price of hairy pigs is high. -- Thank you for sharing.