Success with Batch Farrowing
By John Goss, PIC UK - This is the second of three articles by John Goss dedicated to the improvement of AI technique and results.
Outdoor AI used to be considered problematic, but today most outdoor systems see increased lean growth from stud boars and excellent reproductive performance in the breeding herd.
Interviewing four BQP producers, achieving 23 -25 pigs per sow per year with outdoor sow production using a batch farrowing system, their reasons for success were:
- Attention to detail
- Timing of insemination.
- A positive outlook and team spirit
The four units ranged from 650 to 1000 sows, with three-weekly batch farrowing systems weaning on Wednesday allowing the first service day on Monday. Serving arrangements were all remarkably similar as the successful system has been developed over the last 4-5 years and implemented across the BQP farms.
Good paddock layout is the basis for an efficient, trouble-free handling system. Radial systems with central, designated service areas allowed the holding of sows prior to service without any boar contact. The service area allowed direct nose-to-nose contact with the boar from an insemination area, with a calm, comfortable sow resting area following insemination. A radio was thought essential to improve the ambience for the sows and entertain the staff!
Weaning sows in good condition, score 2.75 - 3.25, following a lactation where high feed intakes were achieved, ensured the sows were really physically and nutritionally ready to return promptly to heat and stand for a good insemination. All units reduced feed to half on the day prior to weaning (Tuesday) to facilitate easier moving of sows on day of weaning, however sows were fed when they had been moved from farrowing to the serving area. All sows were weaned on Wednesday mornings, but on the 1000 sow unit sows were weaned on Wednesday and Thursday, to spread the large number of matings over more days.
Sows were moved to the serving radial and graded by size, age and condition into groups of 18 - 20. Feed was immediately given on weaning, allowing a minimum of 6kg/head of a one stage ration with the idea of "flushing" sows prior to insemination. This level of feed was continued until the following Wednesday when most sows had been served, then dropped back to 3 - 3.5 kg/head/day as the base ration for gestation.
Boars were put in with the sows from the Thursday through to Sunday, considered essential to aid stimulation and catch any early oestrus sows. Boars were taken out on Sunday to remove stimulation prior to the first service day - Monday. Some natural serving activity is seen on Sunday but all farms considered this to be too early to inseminate to catch the optimum ovulation time.
The PIC Sire line semen, in a five day extender, is delivered by
temperature-controlled courier van on Sunday for use on Monday and on Tuesday for use on Wednesday. On farm, the semen is stored in temperature-controlled cabinets at 17 degrees and turned regularly.
Testing for oestrus starts on Monday morning. One paddock of sows is walked from the weaning area to a holding pen outside the service tent, ensuring no boar contact is made. Sows are taken in two's or three's (where there are two operators) to the boar and allowed to stand to be stimulated for a minimum of 30 seconds, essential to give sufficient time to respond to boar presence and react to back pressure test for standing oestrus. Standing sows are served, recorded and marked up with one colour, the remainder being marked with another colour and passed through into a further holding pen. All sows go through this process on the Monday after weaning where the four units found that between 50 - 80% of sows were in standing oestrus on the Monday and were served.
On Tuesday the exercise was repeated, Monday's sows being served again and the majority of the remaining sows being caught. On Wednesday, the sows are run again in front of the boars and served for the second time, and even a third if standing heat is observed.
The units all emphasized the need to have sufficient staff to cover the serving process, two or three for large units, with serving not taking more than three hours, to avoid operator fatigue and ensure attention to detail.
After completion of service by Thursday, running boars are finally put into each of the weaned paddocks to catch any returns. Returns can either remain in their group or be returned to the following batch for service. The basic rule on all farms was no moving or mixing after service.
The four units agreed the following three key points for success:
- Timing of the first insemination - do not be too eager to serve early.
- Allow sufficient time for sows to exhibit standing oestrus.
- Do not rush the insemination process.