How long is a sow's farrowing cycle and reproductive lifespan? Methods to reduce stillbirths at farrowing
In pigs, any female pig that has given birth at any age is called a sow. There are many breeds of sows; by color, there are black sows, white sows, and also spotted sows.So how long is a sow's general farrowing cycle and reproductive lifespan? How to reduce stillbirths at sow farrowing?
How long is a sow's general farrowing cycle and reproductive lifespan?
1. Breeding starts from 7-8 months of age for gilts, with an average of 2.2-2.5 litters per year, and the annual number of piglets provided is generally 20 (abroad it can reach a high level of about 30, indicating that there is still potential to be tapped domestically). The reproductive lifespan of a sow can be as long as 12 years, but the most economical service life for modern lean-type sows in general farms is 3-4 years, and the lifetime production capacity of one sow domestically is about 80 piglets.
2. The sow's production cycle includes several periods such as non-pregnant, pregnant and lactating, corresponding to several main technical links such as mating, farrowing and weaning. In production, feeding management should be strengthened in a targeted manner according to the physiological characteristics of sows at different stages, including the critical periods of successful mating and gestation, so as to increase the annual number of litters per sow and increase production benefits. The feeding time of each stage in the sow production cycle is as follows: weaning to mating stage (feeding 1~2 weeks) - mating and pregnancy stage (feeding 16 weeks) - farrowing and lactation stage (feeding 3~5 weeks).
How to reduce stillbirths at sow farrowing?
In order to reduce the stillbirth rate of piglets at sow farrowing and obtain more live-born piglets, seven techniques for reducing stillbirths at sow farrowing are introduced to everyone:
1. Strengthen feeding management in production, control the body condition of sows at farrowing well, and prevent them from being too fat or too thin. In actual production, the body condition of a sow at farrowing should be full on the back, with a flat upper line, without any protruding bones; below the lumbar vertebrae, behind the ribs and in front of the pelvis there should be a depression, and overly fat sows have no depression. Therefore, pregnant sows before 98 days should be restrictively fed according to the fetal growth and development pattern and the sow's body condition; from 100 days of gestation to 3 days before farrowing, they should be fed freely to full appetite, which can both increase the birth weight of piglets and prevent sows from becoming too fat.
2. Sows must be restrictively fed before farrowing, that is, pre-farrowing feed restriction goes from more to less, and post-farrowing feed increase goes from less to more, to prevent postpartum indigestion in sows. In order to reduce the adverse effects of excessive gastrointestinal burden on farrowing, sows should begin feed restriction 3 days before farrowing (based on the expected farrowing date). The feed restriction standard is: on the 3rd day before farrowing, 3 kg per head per day; on the 2nd day before farrowing, 2 kg per head per day; on the 1st day before farrowing, 1 kg per head per day. When a sow is farrowing, no feed is given during the farrowing meal, and 0.5 kg is fed half a day later. For example, if the sow farrows in the morning, feeding is stopped in the morning and 0.5 kg is fed in the afternoon; if she farrows in the afternoon, feeding is stopped in the afternoon, and on the 1st day after farrowing 0.5 kg is fed in the morning and 0.5 kg in the afternoon; on the 2nd day after farrowing, 2 kg per head per day; on the 3rd day after farrowing, 3 kg per head per day; from 4 days after farrowing to weaning, feed freely to full appetite. That is, pre-farrowing feed restriction goes from more to less, and post-farrowing feed increase goes from less to more, to prevent postpartum indigestion in sows.
3. Prevent constipation in sows before farrowing. It is recommended to mix 1% sodium sulfate and 0.5% rhubarb baking soda powder into the feed 1 week before and after sow farrowing, which can make sow feces soft and moist and help smooth defecation. If conditions permit, pig farms that can use lactation-promoting products are even better.
4. In summer, strengthen heat prevention and cooling work for pregnant sows. This is especially true for sows in late pregnancy and sows about to farrow that are on the farrowing bed. Pregnant sows are kept in crates with high density and difficulty dissipating heat; especially sows in late pregnancy eat more, and body heat increases after eating, with body temperature rising by about 0.5°C compared with before eating, reaching 39.5°C. When the body temperature of sows at 102-110 days of gestation remains at this level for a long time, the stillbirth rate of piglets at farrowing increases. Therefore, when the environmental temperature reaches above 30°C, it is recommended to spray and cool pregnant sows in the breeding house at half-hour intervals, and to flush water to cool sows about to farrow in the farrowing house, so as to minimize the impact of heat stress on sows.
5. Do a good job in vaccination to prevent reproductive disorder diseases in sows, and promptly treat sick pigs, especially sows with fever. To reduce the stillbirth rate of piglets at sow farrowing, it is necessary to strengthen feeding management in production and focus on prevention.
6. Keep the farrowing house quiet. For a farrowing house where sows are giving birth, the house should be kept as quiet as possible, which is especially important for first-time farrowing sows. When a sow is restless, massaging the udder can calm her down, which is very meaningful for promoting smooth farrowing.
7. Place piglets next to the sow's udder to suckle immediately after birth. After piglets are born, wipe off the mucus and dry the hair, then immediately place them next to the sow's udder to suckle. Through the piglets' continuous sucking of the teats, the sow's hypothalamus can be stimulated to secrete oxytocin, causing uterine contractions, which not only helps smooth farrowing and shortens the farrowing process, but also helps milk discharge.