<%@LANGUAGE="JavaScript1.3"%> Swine Production Management - Breeding
Swine Production Management - Breeding
Anatomy of the sow and gilt Gilt selection
Analysis of returns to service Pregnancy diagnosis
Breeding Programs advice on design and insemination Number of females to breed
Detecting heat Signs of estrus
Diseases of the reproductive tract Stockpeople
Enhancing litter size Timing of the mating
Estrus behavior patterns Weaning to breeding interval
Farrowing rate  

Weaning to Breeding Intervals

Effect on production targets:

  • Farrowing rate (assuming a lactation of greater than 18 days)

    Between 3 and 5 days post-weaning there is little reduction in farrowing rate, however, the reduction is dramatic between days 7 and 12
  • Subsequent litter size (assuming a lactation of greater than 18 days)

    The litter size results are from an American example, however, the same pattern can be seen on UK farms associated with larger litter size. The litter size follows a similar pattern to the farrowing rate

Factors that can result in a reduction in weaning to service intervals

Lactation feeding
  • Aim to reduce weight loss during lactation
  • Aim to have a sow eating 10 kg by day 18 of a 18% Protein, 1% lysine, 14.5 MJ diet. Average consumption is required to be over 6.5 kg per day. Additional chromium may help. Biotin to be at 2.25 mm/kg
Weaning to breeding feeding
  • Continue with lactation feed
  • Feed 4 kg a day to point of service - 200-300 mcg/kg
  • Feed once a day
  • Ensure water supply more than adequate, particularly after breeding to help prevent cystitis problems
Day of service to 3 days post-service
  • Feed dry sow ration at 1.5 to 2 kg a day.
  • Sow may not eat much anyway while in estrus
  • Gilts must not be overfed in the immediate period post-breeding as this can affect litter size. Sows are less vulnerable.
3 days post service to farrow
  • Follow dry sow feeding routines
  • First 3- 21 days of gestation increasing feed may help placental growth in sows
  • Overfeeding in gestation will affect subsequent lactation feed intake
Boar exposure
  • Limited exposure only for the first 2 days post-weaning
  • Then 20 minutes a day from day 3 to service. Actual boar contact.
  • Ideally heat check/stimulate twice or even three times daily
  • Remove boar from the sow breeding area, by 10 meters - sight, sound, smell - for one hour before breeding
Breeding barn environment
Water: Adult sows drink 8 to 12 liters per day. If water is supplied through a nipple drinker aim to provide 1.5 to 2 liters per minute. If water is supplied via a front water trough, ensure the water is fresh and clean and refill the trough at least 3 times a day, perhaps providing 5 replenishments in the summer months.
Light and Air: 16 hours of daylight and 8 hours of dark is ideal. The light intensity required is 500 lux, about the light intensity in your kitchen. Many breeding areas are poorly lit. The breeding area must be draught-free and the sows kept at between 16 and 22 degrees C. If the temperature exceeds 22 degrees C cooling is required.
Floor: The floor in the breeding area must provide good footing and ensure neither the boar nor the sow slips on the floor. The flooring in the sow housing must be non abrasive. In many farms metal and tops of bolts can come into contact with the sow and can cause abrasions. Any slatted flooring should be pencil-edged. The sows should be provided with 30 sq ft. Avoid mixing gilts and 1st parity sows with older sows in loose housed accommodation.
Feed: All feed should be fresh and must not contain mycotoxins. Note this means feed barrows should be protected from the rain and feed bins regularly cleaned. Home mixers should regularly check that their ingredients supply the correct mix of ingredients. Feed access particularly between the weaning and time of breeding must be optimized. This may be particularly important for gilts and 1st parity sows. Gilts may benefit for a high energy, low protein ration to help put on backfat without a large frame.
Stock: Ensure that the sow/gilt and boars are of the correct size.
Any signs of lameness
  • Serve by artificial insemination only.

Seasonal effects on farrowing rate

While the domestication of the pig has reduced seasonal effects more dramatically than in sheep (for example), it is difficult to completely negate nature's demands. From the pigs point of view it is unwise to become pregnant in the autumn as the litter would be born in the middle of winter and would likely die. The effects of seasonality are less noticeable in sows reared inside, but for outdoor production systems, the autumn abortion / summer infertility syndrome is a serious problem.

It is imperative that additional gilts are served to cover these periods of reduced productivity.

Do not cull sows until end of breeding week, or ideally at point of pregnancy checking. It is essential to breed sufficient to fill the farrowing area and maximize your pig flow.