The causes and methods of less litter in sows

Female pigs of any age who have given birth in pigs are called sows. In the actual production, it is urgent to analyze the reasons for the small litter size of sows and put forward the corresponding measures to improve the litter size of sows. It is of great significance to improve the efficiency of pig breeding. Let's take a look at the reasons and methods of less litter size in sows.

Variety reason

Some sow breeds have low reproductive capacity, resulting in a small litter size. For example, it is very difficult for Petland and Duroc to increase the litter size due to breeds. In the process of maternal breeding in commercial pig production, we should not only pay attention to the body shape and lean meat percentage of pig breeds, but ignore the reproductive ability, and try our best to avoid the consanguinity of breeds with small litter size. Landrace or large White pigs are recommended.

Age reason

The age and parity of pigs affect the litter size and the live litter size at the same time. The sows with 1 to 2 births had low reproductive performance, less ovulation and litter size. 3The reproductive performance of the fifth parturient was the best, and the litter size and live litter size were the highest. The reproductive performance, litter size and live litter size of sows decreased after 6-7 parturition. And due to the influence of physical strength, the process of giving birth is prone to fatigue, the time is too long, resulting in a large proportion of stillborn fetus. In production, midwifery of pigs with low and high parity should be strengthened to reduce the interval between births.

Feeding reason

1. No nutritious and full-price formula feed for sows: some producers think that sows do not use or use less additives to avoid causing excessive obesity in sows, which is incorrect and must be corrected.

2. Feeding mildew and deteriorating feed materials: excessive mycotoxin in corn, high urease in soybean meal, lack of attention to the quality of wheat bran and poor digestibility of minerals in sows all affect the litter size and live litter size of sows.

Management reason

The main results are as follows: 1. The management before mating: because the breed of pigs grows too fast, mating too early, and does not reach sexual maturity, resulting in a decrease in litter size, the mating age of reserve sows should be over 7 months old and weigh about 120 kg.

2. There is no control of the fat condition before mating: there is no feed restriction for the reserve sows, which results in excessive weight and fat during mating and a decrease in litter size. Basic sows are too thin after weaning, abortion and estrus sows are overfat, which affect the ovulation number of sows, thus affecting litter size.

3. There is no short-term optimal feeding before mating: in order to increase the number of ovulation, the reserve sows were fed with high-quality and full-price feed 3-4 weeks before mating and after weaning, so as to increase the number of ovulation.

4. The feeding amount during pregnancy is unreasonable: 2kg per day in the early stage of pregnancy, 2kg / day in the second trimester, 3kg / day in the later stage, and the feeding amount should be adjusted at any time according to the individual condition of the sow.

5. Excessive stress in sows, such as whipping, shock, brawl, sudden climate change, hot and cold stress, etc., can reduce the number of fetal implantation.

Other reasons

1, the time of vaccination is unreasonable: sows during pregnancy, try to reduce the injection of vaccine, in order to reduce the impact of vaccination on the fetus.

2. The influence of epidemic diseases: many diseases can cause reproductive disorders, resulting in a decrease in litter size and an increase in the proportion of stillbirths and mummified fetuses, such as blue ear disease, classical swine fever and so on.

Matters needing attention

1. Strengthen epidemic prevention and reduce the infection of foreign wild viruses.

2. Reduce the number of introduction, do not introduce species from the epidemic area.

3. Isolation and inspection should be carried out after introduction to prevent the introduction of infectious diseases.

4. Serological examination of sows was carried out regularly, and all kinds of vaccines were immunized according to the health status of sows.

5. Strengthen feeding and management to reduce the reduction of litter size due to management.

6. The pig breeds with high reproductive performance were selected during introduction to improve the production efficiency of sows.