Evaluation of a Commercial Group Sow Housing Alternative.

Evaluation of a Commercial Group Sow Housing Alternative.
Final Report to Manitoba Rural Adaptation Council Inc.
Principal Investigator: Dr. Laurie Connor, Department of Animal Science, Faculty of Agricultural
and Food Sciences, University of Manitoba, Winnipeg, MB R3T 2N2. 204 474-9219.
[email protected]
Project partners: MAFRI (Ron Bazylo); New Standard Ag. Inc. (Kevin Kurbis); Nedap-Velos
Systems (Kees van Ittersum); Eagle Creek Hutterite Colony (Joshua & Jaky Waldner)
Project Duration: April 2009– October, 2011
Project Objectives:
1) Compile and evaluate production performance records of group housed sows in a newly
designed system incorporating electronic sow feeders (ESFs), and compare to industry
standard target values and to published values for conventional and alternative systems.
2) Assess animal health and welfare and animal management ease to facilitate
understanding and utilization of best practices for this type of alternative housing
system in Manitoba conditions.
3) Disseminate results and information to hog producers, industry representatives and
extension specialist through seminars, popular press and industry newsletters.
Background: Manitoba pork producers are faced with the need to shift production practices
away from sow gestation stalls to group or loose housing of sows. At the time of this project
most of the research and evaluations were with smaller herds than is customary in Manitoba.
The layout of group pens, individual feeding of sows and animal management strategies are
critical for the success of any loose housing system. Eagle Creek Colony made the decision in
2007 to build their new 1000-sow barn with loose housing, rather than with gestation stalls.
Their consultations resulted in construction of a barn based on a design originating in the
Netherlands for smaller herds. The Eagle Creek barn was designed to house 750 pregnant sows
in dynamic groups using electronic sow feeders (ESFs) for individual animal feeding.
This project evaluated this system in the harsher climate of Western Canada with a herd
size more representative of the Manitoba situation (1000-3000 sows herds) than of the
Netherlands (200 – 300 sows herds). Evaluation included animal production performance,
animal welfare assessment and management strategies.
The subject barn design was begun in 2007 with construction originally scheduled to be
complete in 2008. However, the start of the project was delayed from August, 2008 until April,
2009 due to set-backs in completion of building construction and installation of equipment.
Subsequently, project activities at Eagle Creek progressed in a timely manner with gilts being
introduced into the facility in groups to facilitate management into breeding/farrowing groups
and training of animals to use the electronic sow feeders (ESFs).
Activity 1 – The Sow barn pre-stocking tour occurred on April 16th, 2009 and was well attended
by producers, industry representatives, MAFRI and media. Over 1000 people attended the
open house. Media coverage received national and international readership, as well as local
1
audiences. Electronic distribution provided links where producers and interested parties could
see different barn designs incorporating the ESFs. The barn layout can be seen in Figure 1.
Activity 2 –Sow productivity and performance – data collection and analysis. The barn was
stocked over a period of time beginning in early May, 2009 with the first farrowings in July. By
January 2010 breeding herd inventory was at 868 females with new animals brought in over the
following months to reach the 1000 sows goal. Swine Books record keeping system was
installed at the onset and used to maintain individual records of all gilts and sows. Swine
Books-generated reports were made available for my review as well as discussions of
performance reports with appropriate barn staff at Eagle Creek were conducted throughout the
study.
Results: The animal flow is such that gilts are trained on how to effectively use the ESF in a
separate training area (Figs. 1 & 2) before they are bred and introduced into the larger dynamic
sow group in the gestation area (Fig. 4) To make adjustment to the large group pen easier, at
first entry to the gilt-parity 1 pen, bred gilts are walked through the whole pen to the ESF area
and locked there so that they know to use one of the ESFs, get fed there and then make their
way back into the group pen.
Over 90% of the matings are by artificial insemination (AI). Weaned sows are housed in
stalls in the breeding area (Fig. 3), mated and introduced into the larger group within 24 – 48
hours following insemination, as long as the sow is no longer expressing estrus behavior.
Weaning/breeding groups are routinely about 40 sows and are normally introduced as a group
into the larger gestation group. The gestation area has three 250-sow pens maintained as
dynamic groups i.e. about 40 animals leave the group each week to go to farrowing and
another 40 animals are introduced after breeding. One of these pens is used for gilts and parity
1 animals. The other two pens are used for multiparous sows. Space allowance is about 24 ft2
per animal which complies with the Recommended Code of Practice for the Care and Handling
of Farm Animals:Pigs (1993).
All animals in gestation are fed individually by ESF (Fig. 4) which is programmed to
provide feed allotment for each animal based on her body condition and stage of pregnancy.
There are 6 ESF stations per pen which has a capacity of 250 animals. Therefore, at maximum
stocking density there is one feeder for 42 animals. Although this may be below what some ESF
promoters recommend, it does mean that all animals, can and do, consume their feed
allotment during a 12 to 14 hour period after the feed drop cycle begins in mid-afternoon. This
has several advantages: 1) animals that need to be sorted by the system for moving to
farrowing or for treatment are in the collection area when staff arrive in the morning and can
then be attended to; 2) any animals that have not eaten are identified early in the day and can
be checked and corrective measures taken; 3) animals are generally quiet and resting during
the early part of the workday facilitating easier walkthrough and checking of animals, including
unusual activity; 4) starting the feeding cycle while stockpeople are still in the barn so that
initial activity around the feeders can be observed and any problems with animal aggression or
with the feeders operations can be noted and dealt with appropriately and 5) since the ESFs are
2
located side-by-side in a specific area, sows can eat at the same time as other sows, without
fear of being bullied. This supports the natural group eating behavior, but since feed per animal
is restricted it also ensures each animal has access to their daily allotment while being
protected from potential aggression from other sows.
Each animal is fitted with a RFID tag which is read by the ESF and also by a hand-held
reader used by the herdsperson as he walks through the pen each day. Loss of ID tags is rare
amounting to one or fewer per month. A 3% loss annually is considered normal. The computer
is checked each day to ensure each animal has eaten. If it appears that she has not, the
herdsman checks the sow to determine if her ear tag is missing or if there is an obvious reason
why she has not eaten. A few pens and stalls are kept available in the breeding area as hospital
pens and for repeat breeders. Boars kept in pens in the gestation barn serve as teaser boars to
detect any sows/gilts that are not pregnant following insemination. Such animals are returned
to the breeding room for a second service or culling depending on her history and situation.
The computer program permits individual animals to be directed into a separate holding area
after they leave the ESF or to be identified with a spray mark on the back, so they are easy to
find in the group.
Monthly performance records were reviewed and very little month to month variation
occurred. Table 1 shows the performance monitor for 3 periods during the study. From the
beginning, reproductive performance of the herd was very good. Parameters that are often
associated with stressful conditions, such as aggression, tended to be equal or better than
industry averages. For example, the percentage of repeat services (i.e. returning to estrus
about 21 days after mating) was low and the farrowing rate was consistently above 90% when
the industry average is about 86% (Deen & Sukumaran Nair). The vast majority of the herds
contributing to this average would still be housed in gestation stalls. Similarly, number of piglets
born live per litter, percentage stillborns and mummies provided no evidence that the group
housing with ESFs was creating stress responses that resulted in lowered reproductive
performance. Even the very low pre-weaning mortality indicates that high viability piglets were
born. Observations of farrowed litters during site visits supported these numbers in that litters
tended to have even sized and vigorous piglets. Overall, even with removing sows from and
introducing sows into an established group on a weekly basis (i.e. dynamic group management)
the herd performance records show no indication of compromised reproductive performance.
About 23% of culls were due to foot and leg issues/lameness. This would translate into
approximately 7% of total culls and is below the published average of 15%. Part of the lowered
culling associated with lameness may reflect the low parity or young herd profile. One could
expect that as average herd parity increases there may be more animals culled due to foot and
leg problems. In part, this is because the herdspeople expressed concern with sows twisting
legs during aggressive interactions on the slatted floor and also with the difference in
orientation of the slats in the ESF area and the walkway through the centre of the pen. Two
concerns were: 1) that the gap between the slats, at one inch, is too wide and sow toes and
hooves get caught or twisted in the gaps, and 2) the slats in the walkway are oriented at right3
angle to those by the feed area. It is speculated that walking along the slats is preferable for the
sows and the change in slat orientation is conducive to twisted hooves and sore limbs.
Activity 3 – Quarterly Welfare Audits and Management Consultation. On-site consultation,
discussions on animal management issues and strategies encountered occurred regularly from
December, 2009 with barn staff at Eagle Creek (Jaky, Hardy, Elijah). Audits patterned after the
Animal Care Assessment tool of the Canada Pork Council were conducted. Cameras were
installed in the sow feeder area and remote access to view sow behaviour at specific times (e.g.
pre-and post-ESF daily reset, when new sows are introduced or when sows are removed for
treatment, rebreeding or to be moved to farrowing) was available for several months in 2010 to
complement on-site observations and assessments. Camera access and function became
sporadic and finally ceased late in 2010. Observation of body condition scores, lesion scores
and group lying patterns were noted during walk-through of the pens.
Results: Usually 40 sows are weaned into stalls in the breeding room, which also houses the
ESF gilt training and breeding area (Figs. 1, 2 & 3). Once sows are inseminated and no longer in
estrus, they are introduced into the gestation group pen. Normally, a group (up to about 40)
animals is introduced into the group already established in the gestation pen. Part of the daily
animal management involves walking the group pens to observe sows, to ensure any newly
introduced sows are settling in to their group and check on any sows the computer identified as
not eating their entire ration. Observations assessing aspects of well-being did not reveal major
issues. While some overt fighting/aggression was noted following introduction of sows, it was
considered to be quite low. Generally, newly introduced animals moved quickly through the
pen to the ESF area. Obvious signs of fighting such as fresh lesions were apparent on some
animals (Figs. 6 & 7) within the first few days of introduction into the group. By the following
week fresh lesions were rare, indicating the animals had settled into their groups and
established their places in the group dynamic. Most fighting or overt aggression appeared to
occur more frequently between members of the newly introduced group rather than between
the newly introduced and established group members. It was not possible, within the confines
of this study, to determine if sows tried to return to the same area of the pen with each
subsequent gestation. The herdsman felt that sows did tend to try to return to the same resting
area, particularly when that was a unique area within the pen, such as along the back wall or
along the spindle gate between the pens. Within each pen the herdsman did note that sows
tended to lay in the same resting area each day with the same pen mates. This suggests the
formation of social subgroups which would be expected.
Using a lesion scoring scale of 0 to 3 (Table 2), within the first week following
introduction into the group pens, fewer than 2.5% of the sows in the pen had lesion scores
above 0. A similar proportion of sows had faded or scarred lesions remaining from encounters
with other sows when entering the group pens some two or more weeks prior to my
assessment. Although some sows were marked along one or both sides (Fig. 6), most lesions
were confined to the neck and shoulder region (Fig. 7). Very few animals had lesions on their
4
hindquarters suggesting that subordinate or timid animals were successful at retreating or
avoiding a potential aggressor.
Table 2 Lesion Scores (fresh scratches i.e. red, inflamed) adapted from Fredricksen et al. 2008
0
no injury
skin unmarked: no evidence of injury from agonistic behaviour
1
slight injury
2
obvious injury
6-10 superficial wounds and/or < 3 deep wounds
3
severe injury
> 10 superficial wounds and/or > 3 deep wounds
< 6 superficial wounds
The layout of the pens facilitated animals finding places to retreat or hide from potential
aggressors. Having partial partitions spaced at 10 foot intervals along the side of the central
slatted walkway provided solid-floored resting areas for small groups (Fig.5) and also a physical
barrier behind which more timid sows could ‘hide’ and avoid contact with more dominant
sows. Animals were found to rest in these solid-floored areas in groups of 8 to 14. In more
open areas near the waterers and feeder areas on the slatted floor larger groups of up to 20 to
30 animals rested together. These are interesting observations, since relatively little
information on preferred group sizes is available in the literature. In this situation when animals
can choose where they lay and with how many other animals, the larger group sizes were
noteworthy.
Aggression around the ESFs rarely resulted in direct bites or scratches. As the start time
for the beginning of the feed cycle approached in late afternoon, some sows would gather
around the entrance to the feeders and some would enter. However, many sows remained in
their resting area until much later when they would be able to access the feeder. This could be
interpreted as the more dominant sows taking their turn at the ESF earlier in the feeding cycle
and subordinate animals waiting for an opportunity later after the more dominant sows had
eaten. In general, sows at the feeder entrance were relatively calm. Some pushing for position
and vocalizations were noted, but not actual fighting or biting. Vulva biting has been noted as a
potential problem with ESF systems that do not have straw to occupy sows waiting by the
feeder prior to feeding time. However, this was not a noted problem in this subject herd which
is housed on bare concrete partially slatted floors.
Body condition of sows was observed at each walk-through of the study. There were
fewer than 1% of sows in gestation with body condition scores of 2.5 which corresponds to
thin. With one exception these were animals within the first three weeks of breeding and entry
to the gestation barn. The remaining animals were judged to be a score of 3.0 – 3.25
(good/average body condition). Part of the feeding strategy practiced in this operation is to
feed each animal on a computer generated feeding curve which provides increased amounts of
feed for those animals requiring additional weight gain in early gestation, and less feed for
those considered in satisfactory body condition. The herdsman can input any changes with his
handheld reader if he determines the animal’s condition is above or below what it should be for
the stage of pregnancy.
5
At each visit, I walked the pens either on my own or accompanied by the herdsman. Sow
temperament was generally calm with very few animals showing any signs of fearfulness. Most
animals ignored us as we walked through, a few would follow us and a very small number
would not allow me to approach them within a meter. The herdsman had not noticed that any
of these more “timid” or wary animals were less productive, but stated that he had not really
looked for this when analyzing records.
Conclusions:
The design/layout of the Eagle Creek commercial sow barn was conducive to good
animal flow, good animal care and ease of animal management.
Animal performance was above average, with repeat services, pregnancy rate and
farrowing rate indicating that conditions in gestation were not unusually stressful and
did not compromise animal performance.
Body condition scores, body lesion scores and observation of animal responses to each
other and to people support that animals adjusted well to this gestation housing,
aggression is minimal and is mainly associated with the first day of mixing newly
inseminated sows into the group.
Features considered to contribute to the success of this housing design include: the
width of the alleyways; ample room around the ESFs entrance; the ability of the animals
to entry and go through the feeder even if they have already had their daily allotment;
the release of animals from the feeder into a separate area away from the entrance, the
partitioning of solid floored areas into defined resting areas and the general flow of the
animal movement in one direction.
The ability to direct animals into a separate segregation area after they exit the feeder
decreases the labour required to find animals and sort them out of the group pen by
hand.
The stockmanship was excellent and walking through the pens and observing the
animals daily as well as attending to any perceived problems immediately is a significant
contributor to the success of this facility
Information is still needed on best slat and gap width for ease of animal movement
without compromise to hooves and legs, while still allowing manure movement through
gap.
One herdsman is primarily responsible for day to day duties of checking sows, ensuring
feed intake; assistance needs to be available for moving or treating sows in the group
housing area but in practice was rarely needed.
Stockperson skills, observation and understanding of pig behavior are essential, but this
particular system lends itself very well to accommodate natural animal social behavior,
while facilitating individual feeding and attention as required.
Activity 4. – Dissemination of results. Update of results to date was planned for Hog Days,
2010. However, the format presentation determined by the Organizers precluded this. A
summary was presented as part of a presentation on research activities by the Department of
6
Animal Science at Hog Days. Results/outcomes of this project have been incorporated into
several other presentations on alternative sow housing including presentations to Swine
Innovation Porc (producer Board members, scientists and allied participants), Manitoba Pork
Board of Directors and to Focus Group participants of the MRAC funded project - Successful
Sow Barn Conversion. Also, one of the collaborators (Kurbis) made a presentation at Manitoba
Swine Seminar (2012) on the Eagle Creek group housing system. Report of these outcomes also
available on the NCLE website.
References:
Canadian Pork Council. 2010. Animal Care Assessment Manual. http://www.cqaaqc.ca/aca/documents/ACA-Animal-Care-Assessment.pdf
Canadian Pork Council. 2010. Animal Care Assessment Manual. Appendix 10 - Body Condition
Scoring for Sows. http://www.cqa-aqc.ca/aca/documents/ACA-Appendix-10.pdf
Deen, John and Anil Sukarmarin Nair. 2010. Summary of the 2010 Data (PigChamp).
http://benchmark.farms.com/Summary_of_the_2010.html
Fredriksen, Bente, Bjørn Magne Lium, Cathrine Hexeberg Marka, Birgitte Mosveen, and Ola
Nafstad. 2008. Entire male pigs in farrow-to-finish pens—Effects on animal welfare. Applied
Animal Behaviour Science 110: 258–268
Kurbis, Kevin. 2012. Eagle Creek: Experiences in Loose Housing. Manitoba Swine Seminar
Proceeding 26:39-48.
Recommended Code of Practice for the Care and Handling of Farm Animals:Pigs. 1993.
http://www.nfacc.ca/codes-of-practice/pigs
*Report submitted by Laurie Connor, Dept. of Animal Science, University of Manitoba. Contact
ph: 204 474-9219. email [email protected]
7
Figure 1. Floor Plan for 1000-Sow Herd with Dynamic Groups of up to 250 Sows per Six
Electronic Sow Feeders (ESFs)
Breeding Stalls
Feeding areas with 6 ESFs each
Gilt training/breeding
Group Gestation area
Figure 2. Gilts at ESF in training area
Figure 3. Stalls in breeding area
8
Table 1. Eagle Creek Herd Performance (Swine Books) & Median Values for Key indicators of
Performance in Canadian Herds using PigChamp1.
First 6
Next
Last 9
Pig Champ
months
12months
months
CDN
(2009)
(2010)
(2011)
Median
Average Female Inventory
654.7
964.4
1025.1
471
% multiple matings
95.9%
96.7%
97.1%
-% Repeat Service
2.7%
4.3%
2.4%
7.3
st
Weaning –1 Service Interval (d)
7.2
6.3
5.4
--2
Percent Sows Bred by 7 Days
83.0%
94.2%
96.2%
--Farrowing Rate (%)
Average Parity Farrowed
Litters / Mated Female/Year
Average Live Pigs Born per Litter
Average Pigs Born Per Litter
Percent Stillborn
Percent Mummies
95.2%
1.0
2.66
12.20
13.46
6.8%
2.6%
93.5%
2.0
2.47
13.19
14.79
7.4%
3.4%
95.5%
3.2
2.54
13.70
15.41
8.3%
2.8%
85.8 %
--
PreWeaning Mortality Rate
Ave Weaning Weight/Pig Weaned
(kg)
Ave Weaning Age (d)
Pigs Weaned per Female Weaned
Pigs Weaned per Mated Female/
Year
6.5%
8.0
5.4%
7.8
7.1%
7.5
11.94
7.4
27.3
11.3
26.95
25.7
12.4
30.72
26.2
12.8
32.46
20.60
10.3
24.57
1015
2.5
36.91%
30.41%
1.7%
24.5
148.1
96.8%
---39.38
7.50
----
Ending Female Inventory
868
987
Average Parity
0.13
1.36
Replacement Rate
212.99%
42.51%
Cull Rate
12.3%
26.5%
Death Rate
2.5%
2.0%
NPD/Mated Female/Year
--27.8
Average Farrowing Interval
NA
150.9
Percent AI matings
93.3%
96.5%
(-----) values not available and not considered key values by analyst.
11.60
13.11
7.4%
2.4%
9
Figure 4: Sows at ESFs in feeding area
Figure 3. Sows gestation pen. View of
waterer area, partitioned resting areas
and slatted walkway
Figure 5. Sows in partitioned solid-floored
resting area adjacent to slatted walkway
10
Figure 6. Lesions on neck, shoulder and along body
Figure 7. Lesions on neck and
shoulder from fighting.
11