1, identification of sow estrus
Sows are restless, sometimes named, their genitals are congested and red, and they have the behavior of climbing over other pigs. When sows reach the peak of estrus, their vulva is full, they climb more frequently, and sometimes they stay still, as if thinking about life.
2. Selection of mating period of sows
When you find a boar to try, the sow will take the initiative to show it to the boar; When a person comes to the sow in heat, it will slowly approach the person with its ass and push it. When the sow in estrus is pressed by hand, it will stand still no matter whether it is fidgeting or standing still before. If sows have the above symptoms, it should be the best time to breed.
3. The age of sow determines the mating time.
The principle of sow reproduction is that the old is early, the young is late, the old is not old and the young is in the middle. The estrus of piglets is about 6 days, and it is best to breed on the second to third day of estrus. The duration of estrus in aged pigs is about 4 days, so sows should be bred the next day.
3. Free-range sow reproduction
Most pig farmers in rural areas are free-range households, and most of them raise boars themselves, so they need to find someone who specializes in raising boars. Pay attention at this time. Generally, boars are used frequently by merchants who specialize in breeding. Before breeding sows, we must first know how many times boars have bred on the same day. If you have been raised twice or more, it is best not to raise pigs. You should choose other boars to breed, or make an appointment with the boar breeder to breed the next day.
4, sow breeding method
Boars of the same size should be selected for breeding. Sows generally choose to breed once and twice in estrus, and the interval between the two breeding is about 10 hour. Sows should sometimes assist in reproduction and help boars put their animals in the right place in time.
There are several ways to breed sows.
1, single mating
In other words, sows only mate with boars once in estrus. The advantage of this breeding method is that it can improve the utilization efficiency of boars, but if the breeder is inexperienced and can't master the optimal breeding temperature of sows, the conception rate and litter size will be affected.
2. Repeated breeding
That is, sows breed with the same boar twice in one estrus, and breed again at intervals of 8-24 hours after the first mating. This breeding method can increase the chances of egg fertilization and improve the conception rate and litter size of sows. In production, multiparous sows all adopt this method.
3. Double breeding
That is, two boars of the same breed or different breeds are bred every 10 ~ 15 minutes in an estrus cycle of sows. This breeding method can promote sows to ovulate more, and eggs can be fertilized by sperm with strong vitality, thus improving the conception rate and litter size of sows, which can be used in pig farms that produce commercial pigs. However, in pig farms or sows preparing to keep seeds, two-line breeding cannot be adopted, otherwise the pedigree will be confused.
4. Breeding for many times
That is to say, in an estrus cycle of sows, the same boar is mated three or more times, and the mating time is 12, 24 and 36 hours after estrus, respectively. Although this breeding method can increase the litter size, due to repeated breeding, it increases the chance of reproductive tract infection, easily causes reproductive tract diseases in sows and reduces the pregnancy rate.
How to protect the fetus after sow mating
1, sows are prone to miscarriage 9 ~ 13 days after mating and 2 1 day before delivery. Therefore, in particular, measures to protect the fetus should be strengthened, and protein, minerals, vitamins and other rich feeds and green and juicy feeds should be supplied as much as possible to avoid feeding frozen, moldy and deteriorated feeds.
2. Pregnant sows should try to avoid mechanical stimulation, such as squeezing, biting, slipping, whipping and scaring.
3, pig breeding should be recorded in detail to avoid inbreeding.
4, pig farms to engage in disease prevention and control work, found that the disease in a timely manner.