Management of Pregnant Sows
Silent Heat in Sows
Most sows suffering from silent heating are those exposed to overcrowding in a badly matched groups, poor nutritional state and extremely high temperatures. Others are those poorly housed in confinement stalls, no boar contact and little light stimulation. Management practices such as flushing, provision of physical exercise, social contact, boar exposure, fasting and use in injectable hormones can be of great help.
Management of Pregnant Sows
Successful management of pregnant sows is the final, vital step in mating and reproduction. If managed well, sows will farrow as scheduled producing large litters and quickly returning to heat for breeding after weaning. The number of empty sows and culls will be reduced. A higher output and lower cost of production from the piggery is expected.
To attain these objectives, the following management practices are recommended:
1. Pregnancy control
Day 21 (return to service)
A good recording system will signal which group of sows are due to return checks- you can make use of either computer action lists, wall chart or sow calendar for those manually recording.
When and how to check for pregnancy
The expected return date is 21 days after mating but can occur from day 18 to day 24. So be on the lookout either side of day 21. Sows should be checked twice daily during this period. Returns to service should be checked using the Back Pressure and/or Boar tests. A good pen layout that makes this task easy is a major benefit. If a detection mating area is designed, take the sow to the boar area. If sows are in stalls, take the boar to the stalls to help the caretaker do the check.
Other Methods of Pregnancy Diagnosis
Records
Ultrasound
Hormone injection
External signs
Blood and urine examination
Scanner
Remember: It is important to do return checks carefully if return rate is high.
Day 25 (Start of pregnancy check)
The reliability of a pregnancy tester is quite good about four to six weeks after mating, but they do not substitute for an accurate return check around day 21. Because pregnancy tester does not have to be done on a particular day in the sow’s pregnancy, make best of the time by testing one or two weeks worth of sows on the same day -–sows mated four and five weeks ago can be tested on the same day. Pregnancy testing is useful in herds where farrowing rate is low with many sows returning at irregular interval. Day 42 (second heat control) The second heat control checks if the sow returns to heat or not. The heat detection can be done on the 36th day up to the 48th day after breeding or mating. At this stage, the stockman is assured that the sow is pregnant if it does not return to heat, considering the condition of the sow.
2. Increase feed allowance
30 days before farrowing
Increase the feed amount to be given to the sow due to the following reasons:
Fetus development
Body reserve for the lactation period
3. First mange and lice treatment
14 days before farrowingBefore treatment of external parasites, clean the sow thoroughly with soap, scrubber and water. Let the sow dry then apply the biologics for the treatment of mange and/or lice. These are either pour-ons, sprays or injectables. The latter is more expensive.
4. Deworming
10 days before farrowingThis practice is very esssential for the health of both the sow and piglets. Application msy either be through in-feed medication, which is more economical, or by injection.
5. Second mange and/or lice treatment
7 days before farrowing
A follow-up treatment is done to kill the remaining eggs of the mange and lice which are still on the sow’s body. However, if injectable biologics are used, there is no need for the second treatment.
6. Transfer to the farrowing pen
7 days before farrowing
The sow must be transferred to the farrowing pen for it to be acclimatized to the new pen and environment.
7. Decrease the feed allowance
3 days before farrowing
This practice is done to avoid constipation and difficulty in farrowing.
Critical Periods For Successful Breeding