Recommended dimensions and details for building PigSAFE pens

(November 2010)

The PigSAFE Project: Developing an alternative to the farrowing crate

The PigSAFE Project (Piglet and Sow Alternative Farrowing Environment) is a three year

project which started in April 2008 with the objective of developing and testing a practical

non-crate system for indoor farrowing accommodation. The project is funded by Defra and is

being carried out by the University of Newcastle and the Scottish Agricultural College (SAC),

in consultation with both welfare (RSPCA) and industry groups (BPEX, QMS).

Further details of this project, including the work carried out in the first year, the prototype

designs tested at Newcastle (farrowing crate conversion, slurry system) and SAC (new build,

solid manure system) over this period and our experience with them can be found in a

PigSAFE Interim Briefing Note published in February 2010 and available from us on

request.

Although the project is still ongoing, we are being approached by many producers wishing to

try a prototype on their own farms and have therefore produced this document which details

our present views regarding design and pen dimensions. Whilst these are our best current

suggestions, based on experience with working with these pens, it should be noted that we are

still working on the development and evaluation of this prototype and final results and

conclusions may therefore differ from those available at present. Whilst this information is

given in good faith, we cannot accept any responsibility for the consequences of its

adoption by others.

We consider that the detail of the design is very important in its performance and

therefore any deviation from the details given in this document is done so at the producer’s own risk. We encourage anyone wishing to build pens to contact us for a more

detailed discussion of key features. Visits to view our prototypes are welcomed by prior

arrangement.

For further information please contact:

Prof Sandra Edwards Dr Emma Baxter

University of Newcastle SAC Edinburgh

0191 222 8350 0131 535 3214

sandra.edwards@ncl.ac.uk emma.baxter@sac.ac.uk

Recommended dimensions and details for building PigSAFE pens

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NB: These recommendations are based on our experience designing and working with PigSAFE pens. This information is given in good faith, but we can accept no responsibility for its adoption, especially if design criteria are modified when building the pens. Anyone thinking of constructing such pens is recommended to contact us for more detailed discussion of the key features, and visits to view the prototypes are welcome by prior arrangement.

KEY:

Slatted area – 9-10mm void width with Triband stainless steel or plastic slats

Solid nest area – recommended with small perforations to aid drainage Barred areas – “Chat-holes” to allow contact between pens. Solid at base. Direction of movement for walls or gates. Heated area – under-floor/mat heating recommended when using nesting substrate Light in creep Sloped walls suspended 200mm above floor and 180mm at base from pen wall. Combined sow and piglet drinker with anti-flood bar around piglet drinker

24

00m

m

3715mm

12

00m

m

1300mm 2400mm

60

0m

m

50

0m

m

CREEP

SOLID NEST AREA

Removable step

SLATTED DUNGING AREA

FEEDING STALL

Barred access gate that can lock sow in nest for passage along the dunging area

43

0m

m

80

0m

m

1700mm

560mm

610mm

540mm

Nest wall can open up 7 days post-farrowing

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4

Creep area = 0.75m2 (if you have the room, 1m

2 would be better – the actual

recommendations are 0.96m2 for 14, 4 week weaners). Corner creeps are important (not

front) as this helps with nest shape and makes it easy for piglets to access from the udder.

� The front of the creeps has two protruding, but

graduated bars that prevent the sow lying flush against

the creep face and “locking” the piglets in. The

protruding bars are graduated so that at sow’ shoulder

height she is unlikely to bump into them. There is a

gap at the bottom (200mm from the floor) to allow

the sow’s udder to be unimpeded during suckling but

means she cannot get her shoulders under there when

lying. The gap between the protrusions and the rest of

the creep face is 180mm. We recommend the

undersides of these bars are rounded off to prevent

injury.

� Gaps/voids between creep bars measure 180mm to

allow weaners to exit the creep without damaging

their shoulders.

� On the outside edge, the creep wall is only 600mm tall

to allow easy access to the piglets. The inside edge is

1200mm high with vertical bars to prevent sow

climbing and jumping.

� A better “close-in” of piglets in the creep is

recommended and photographed below is a ratchet

mechanism (seen in a Danish system) that allows you

to shut the piglets in without opening the lid and

allows control of the micro-climate, by adjusting the

height of the boarding on the front of the creep.

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Details: Sloped walls: these are here to assist with careful lying down of the sow and protect the

piglets because the sow cannot lie flush against the nest walls and therefore crush against

them. Sloped walls are around the whole nest, including the access door. Sows prefer sloped

walls to farrowing rails. Research shows that sows will lie unassisted rather than use a

farrowing rail. The sloped wall also allows piglets to walk around the sow during farrowing,

so that they can seek the udder and teats unimpeded.

� The bottom part of the slope is at a distance from the wall of 180mm (basically shoulder

width of big 4-week weaners) and at the top the distance is 25mm. The height from the

ground is 200mm (allows little piglets to escape and the sow cannot get her shoulders

under).

• The kick-boards/steps between the nest and

the dunging passage can come out as soon as

the piglets start using the creep. This step has

a recommended height of 150mm. In addition,

the wall dividing the dunging passage from

the nest is on hinges and moves back after 7

days post-farrowing. If you can incorporate

this flexible feature we would highly

recommend it, to optimise nest hygiene. Make

sure the swinging wall is as close to the main

wall as possible; because of the hinge you

need to have certain clearance to open up but try not to have a big gap as this creates a

draft. If this feature cannot be properly incorporated, a pop-hole can be put into the

dividing wall (between nest and dunging areas) and lifted up after 7 days post farrowing.

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Flooring: Slats = we recommend that the slats are either Triband stainless steel with a 9mm void or

plastic (not concrete). The void should not be greater than 10mm because piglet foot injuries

are more likely with larger voids. The legal maximum void width for piglets is 11mm and

any flooring must adhere to the requirements detailed in the Defra Code of Recommendations

for the Welfare of Pigs

(http://www.defra.gov.uk/foodfarm/farmanimal/welfare/onfarm/documents/pigcode.pdf).

� It is recommended that all areas other than the nest and creep should be slatted.

� The solid area in the nest can be concrete or solid plastic tiles with occasional small

perforations to help with drainage. This latter option is recommended, but careful slat

choice is required to ensure they are adequate for the weight of heavy sows and have

sufficient profile to minimise slipping. In addition producers should seek advice from slat

suppliers on likely wear rate of slats over time to make an informed choice.

� A good support structure underneath the pen is needed as the sows will be walking

around more and therefore there are greater levels of stress to the floor in “busy” areas

(i.e. over the step)

Sow and piglet combined drinker = the sow drinker height is 700mm from the floor and the

piglet drinker height is 200mm from the floor. These are placed in the dunging area, and an

anti-flood bar is recommended around the base as sows like to cool-down using the piglet

drinker and can sit on the piglet drinker if it is not protected. Position the drinker so that the

sow is going to walk fully out of the nest to drink. If a drinker is put in the feeder too, a

slatted floor is recommended underneath.

Chat holes between pens = these are an important feature of the pen.

� Having these contact areas are helpful for gilts

that tend to react when first separated from the

group. They allow contact throughout

lactation and the theory is, weaning stress and

post-weaning fighting is reduced.

� Because these areas let a lot of light into the

pen they give the nest-space more of a sense

of enclosure and attract the sow away from

open areas and into the nest area to farrow –

which is the safest area for the piglets.

� It is also important to use the metal bars

rather than slotted plastic. The slotted

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plastic does not allow full nose to nose contact and can be very dark. These barred areas

have a 65mm void between bars and are positioned 400mm from the ground.

� It should be positioned mainly in the dunging area with visibility from the nest area into

the corresponding pen. Chat holes are also on the other side of the dunging area to

maximise contact areas outside of the nest-site and to discourage animals from

farrowing in the dunging area.

Access gates are recommended in the

dunging area and therefore the barred areas

need to be incorporated into these access

gates. It is recommended that the access gates

are on hinges that allow them to be swung

both ways. This allows ease of movement

between pens when moving sows in, but it

also gives the option of shutting the sows in

their nest areas for passage along the dunging

area. As with any features that incorporate

hinges it is important to minimise the gap

between walls and doors and therefore

minimise the risk of drafts.

Kick-boards/steps to stop straw and piglets being in dunging area: To separate off the dunging area from the nest area we

slot in plastic sheeting which is approximately 150mm

high. This allows the sows to step over and drink and

dung but keeps newborns and straw in the nest site. A

higher step would be more effective in retaining straw,

but we have found it deters some animals from nest

entry.

Under-floor heating = The creep being heated (30°C)

is essential and under-floor or heat mats, rather than

heat lamps, is recommended because of the use of

substrate for nest-building activity. A creep light is also

recommended to attract piglets into the creep.

Substrate = We recommend a minimum of 2kg (~2

leaves of a small bale) of long-stemmed straw for nest-

building and farrowing. Depending on the manure

handling system, this can then be reduced from ~ 24h

post farrowing to recreational, chopped straw and

sawdust given daily

Positioning of the pens = the pens are set up at

SAC as rows of six and in Newcastle as rooms

of four. Basically there are always even numbers

because they are designed to be mirror opposites

of each other and work best if each sow has a

neighbour.

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Building tips and challenges:

DOORS � Avoid gaps between access doors and walls and floors: We

recommend the hinges for the doors are placed on the outside

of the pen so that the access doors open fully and the full width

is achieved for the sow to go in without scraping her sides. The

doors need to be cut correctly and hung correctly so that they

hang flush to the sides and the floor (minimal clearance

distance) to prevent drafts and any escapee piglets. Additional

pieces of plastic flapping can be stapled on if there are any

obvious areas that could create drafts.

FEEDER FOR SOWS: The feeding area for the sow was designed

to be wide enough for a sow to fit in and feed but not too wide so that

she could lie laterally and farrow in there.

� Width and height: It has a lock-in feature (similar to the

individual feeders in a dry sow house) so that you can handle the

piglets safely while the sow is feeding. However make sure the

feeders are tall enough for your largest sows to get in without

scraping their backs. We would recommend a height of no less

than 1100mm, especially at the point of entry (the gates that lift

over the back, when open hang lower than the overall height of

the feeding stall, so make sure this is taken into account).

� Feeder bowl: The feeder bowls should be flush to the floor (no

gap). We would recommend a feeder bowl that is smooth (no edges

where old feed can collect) and preferably plastic, as galvanised

steel can be sharp. In addition we recommend that they are either

able to be removed for cleaning or a hinge mechanism put in place

to empty any old feed. Another possibility is putting a gromit in the

bottom (inaccessible to the sow) to allow drainage of water post-

pressure washing.

� Sows nudging feeder shut: Some sows nose the bars of the lock-

in feeder and once loosened can shut themselves in. We have put a

clasp on the feeders to prevent this (see picture).