Performance of Pigs in a Swedish Bedded Group Lactation and Nursery System
Monday, February 26, 2001By Iowa State University Researchers - In the 1980s, Swedish swine producers were forced to develop several production models to remain profitable due to the strict legal policies facing the swine industry. By 1994, approximately 150 Swedish farms were using a sustainable model for pig production. This model, was a deep-bedded, group housing system for pregnant, farrowing, and nursing sows and their litters, was known as the Västgömodel.By M. E. Larson, graduate research assistant,
and M. S. Honeyman, associate professor,
Department of Animal Science; Iowa State University
Summary and Implications
A Swedish deep-bedded, group housing system for
pregnant, farrowing, and nursing sows and their litters was
demonstrated. There are two versions of the Swedish
system. Previous work examining the one system by
Honeyman and Kent (1,2) concluded that pig growth
(55–60-lb pigs) was excellent, and prewean mortality
(18.4-28.3%) was the weakest part of the overall system.
The second system was demonstrated in this study to
reduce prewean mortality, whereas maintaining or
improving nursery phase performance. Prewean mortality
was reduced with the conventional farrowing crates (2%)
used in conjunction with the bedded group lactation
system.
The preweaning mortality of the Swedish bedded
system can be reduced by keeping the sows and litters in
farrowing crates for the first two weeks until movement to
the group lactation room.
The rate of gain for the first week
of group lactation (14-21 d) was 24% less for the group-lactated
pigs than for the conventional pigs; however,
during the next week the group lactated pigs grew 65%
faster than the conventionally weaned pigs. Overall, the
growth rate was similar, the group lactated pigs grew 7%
faster than the conventionally weaned pigs. Additional
research documenting the Swedish housing system is
planned.
Introduction
Ljungström and Thorstensson are two
versions of the Västgömodel system. In the Ljungström
system, sows farrow in conventional pens and are moved
with their litters to group nursing rooms after the pigs are
10 to 14 days old. In the Thorstensson system, sows farrow
in group nursery rooms in temporary wooden farrowing
boxes, which are removed after the pigs are 7 to 10 days
old and have began to climb out of the boxes. Group
lactation ensues (1).
In 1995, an existing 1950’s style hog house was
retrofitted as a deep-bedded facility to demonstrate the
Thorstensson housing system at the Iowa State University
Armstrong Farm, Atlantic, IA (1).
In 1997, Honeyman and Kent (2) summarized the results
of 1-year operation of the Thorstensson housing system.
Weaning occurred at 4.5 weeks of age (29.3 to 35 d). At
weaning, the average number of pigs per litter was 8.5
pigs/litter with a weaning weight average from 17 to 28
lb/pig. After weaning the pigs remained in the nursery for 30
days and were sold at 60 days of age. Pig growth in the deep-bedded
nursery was excellent with 60-lb pigs at 60 days of
age and 1.25 lb/day average daily gain during the nursery
phase.
The authors concluded that the weakest part of the
overall system was prewean mortality. Prewean mortality
was 18.4 to 24.2% double the industry standard. Most of the
mortality occurs during the first few days of life.
By 1999, five more groups in the Thorstensson housing
system were analyzed and summarized. Nursery phase
growth was excellent resulting in 55-lb pigs with a 1.22
average daily gain. Prewean mortality was 28.3 with 81% of
the piglet death occurring by three days of age (3). These
results were consistent with previous work by Honeyman and
Kent (2). The authors concluded that the system would
perform well if prewean mortality could be reduced (3).
Preweaning mortality may be reduced by farrowing in
conventional farrowing crates or pens and by moving the
sows to group lactation when the pigs are 7 to 10 days old
(Ljungström).
In 1999, The Ljungström system was demonstrated at
the Iowa State University Armstrong Farm. The Ljungström
system was implemented to reduce prewean mortality, while
maintaining or improving nursery phase performance.
Methods and Materials
Seventeen sows were farrowed in conventional
farrowing crates at the Iowa State University Lauren
Christian Research and Demonstration Farm, Atlantic, IA.
The trial was conducted in February and March. The sows
were assigned to two treatments: conventional weaning (<21
d) and a group lactation with a 35 d weaning. On day 21, the
conventional weaning group pigs (n=51) were weaned and
placed in a fully enclosed mechanically ventilated
confinement nursery with a plastic total slatted floor. There
were eight pens (5 × 13 ft) in the experimental room and the
middle four pens were used for the trial. Each pen was
equipped with one nipple cup waterer and a 6-hole feeder
(35.9 × 11.7 × 28.3 in.) with feeding spaces 5.7 in. wide and
4.0 in. deep. All conventionally weaned pigs had ad libitum
access to four commercial diets in phase and water
throughout the 60 d trial. On day 14, the group lactation
piglets and sows were transported 7 miles to a straw
bedded group lactation building at the Iowa State
University Armstrong Farm. For the next 21 days, the sows
lactated as a group and were given ad libitum access to
feed. The piglets had access to creep feed. On day 35, the
sows were removed and the piglets were fed three
commercial diets in phase for the remaining 25 days of the
60 d trial.
Results and Discussion
Performance of the two groups of sows and their pigs
in the conventional farrowing room is shown in Table 1.
The average number of pigs born alive per litter was 9.6
pigs for both systems. The average birth weight was
similar (3.2 vs. 3.3 lb/pig).
Previous work by Honeyman and Kent (1) concluded
that prewean mortality was high (18.4 to 24.2%) in the
Thorstensson housing system, but that it may be reduced
by using the Ljungström housing system. Prewean
mortality was reduced in this study with the conventional
farrowing crates (2%) used in conjunction with the bedded
group lactation system (Table 1).
Weaning occurred at 21 days for the conventional
weaned pigs and 35 days for the group lactation pigs. The
group lactation sows weaned 9.6 pigs/litter and the
conventionally weaned pigs had 9.6 pigs/litter.
Pig growth data are shown in Table 2. The weaning
lag for the conventionally weaned pigs is apparent. The pig
growth rate decreased 32% when comparing the week
before weaning to the week after weaning. Growth rate for
the group-lactated pigs increased steadily, including the
week after weaning. The rate of gain for the first week of
group lactation (14-21 d) was 24% less for the group
lactated pigs than for the conventional pigs; however,
during the next week the group-lactated pigs grew 65%
faster than the conventionally weaned pigs. Overall, the
growth rate was similar, the group-lactated pigs grew 7%
faster than the conventionally weaned pigs.
Comparisons of feed intake and costs were not
attempted. The conventionally weaned pigs required special
diets beginning with the 21 d weaning. The group lactation
pigs consumed some creep feed during the days 21–35. Also,
the sows consumed greatly different amounts of feed. The
conventionally weaned sows were limit fed after 21 days, but
the group lactating sows were fed ad libitum for days 21–35.
Other major differences probably included the
subsequent sow reproduction performance (wean-to-estrus
interval, conception rate, litter size), housing costs, bedding
costs, sow fatness, etc. However, it is clear, that the
preweaning mortality of the Swedish bedded system can be
reduced by keeping the sows and litters in farrowing crates
for the first two weeks until movement to the group lactation
room. Pig growth in the bedded group lactation and nursery
room was equal to pigs conventionally weaned into a modern
nursery facility with environmental control.
Additional research documenting the Swedish housing
system is planned.
Acknowledgments
The authors gratefully acknowledge and appreciate support
by the Leopold Center for Sustainable Agriculture, Ames, IA,
the Wallace Foundation for Rural Research and
Development, Atlantic, IA. and Dennis Kent and the farm
staff.
To view the full report (pdf format) Click Here
References
1. Halverson, M. and M. S. Honeyman. 1997. Swedish
deep-bedded group nursing systems for feeder pig
production. SA-12. Iowa State Univ. Ext., Ames.
2. Honeyman, M. S. and D. Kent. 1997. First year results of
a Swedish deep-bedded feeder pig production system in
Iowa. ASL-1497. Swine Research Report. Iowa State
Univ. Ext., Ames.
3. Honeyman, M. S. and D. Kent. 1999. Performance of a
Swedish deep-bedded feeder pig production system in
Iowa. ASL-1683. Swine Research Report. Iowa State
Univ. Ext., Ames
© 2000 - 2012. 5m Publishing, Benchmark House, 8 Smithy Wood Drive, Sheffield, S35 1QN, England. - A Benchmark Holdings Ltd. Company