Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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FLOORING SYSTEM FOR FARROWING PEN
This invention relates to a flooring system for use in a farrowing pen
for animals and particularly for pigs.
BACKGROUND OF THE INVENTION
In the intensive raising of pigs, the sow at the time of birthing is
moved to a farrowing pen which includes a farrowing crate which defines a
central area in which the sow can lie and a two side creep areas in which the
piglets can lie, move about and can move to the sow for accessing the nipples.
The farrowing crate generally includes a metal framed structure
which confines the sow so as to prevent the sow from Iying in the side areas andthus crushing the piglets. The crate and flooring system allows the sow to standso that the sow can feed from a feeder located at a front of the crate on an outlet
door. The crate is generally bolted to the flooring system or to the surroundingconcrete structure so that it stands up from the floor and extends from the front to
the rear of the pen.
Underneath the pen is provided a manure containment pit and over
the pit is mounted a flooring structure on which the sow can lie and stand and on
which the piglets can lie and move.
The farrowing pens are generally arranged side by side in a row
with the front gate opening on to an alley way.
In recent years, the importance of a high level of sanitation in the
production of pigs has been appreciated to avoid transfer of diseases from one
litter to the next. The purpose of the pit and the supporting flooring system above
the pit on which the animals stand is in order to provide improvements in hygiene
so that the manure from the animals falls through the floor into the pit and is
separated from the animals standing on the floor. The floor can then be cleaned
to prevent bacteria, viruses and funguses from being harboured in the flooring
and pen system.
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This type of system using a pit was implemented in approximately
the 1950s. The first type of flooring used for the purposes of extending across
the pit and supporting the animals was in many cases a simple wooden flooring
formed from a series of parallel slats. At around the same time, aluminum
flooring was also used in the form of extruded elongate T-bars. The vertical webof the T-bar provided sufficient strength to enable this structure to span the length
of the farrowing crate which is generally of the order of 7 feet. The T-bars had a
horizontal upper surface and were mounted side-by-side so that the bars were
arranged in spaced position with a slot or opening between the two adjacent T-
bars allowing the manure to fall through for collection in the pit.
The aluminum T-bars had two disadvantages. Firstly, any electrical
conduction between the aluminum T-bars and another conductive material
generated a highly aggressive corrosion caused by galvanic action. In this
corrosion, two dissimilar materials, such as the steel of the farrowing crate and
the aluminum of the flooring, in conjunction with an electrolyte provided by theliquid manure provides a galvanic action rapidly corroding the aluminum T-bars.
Galvanic corrosion is particularly pernicious in that it is generally invisible but
degrades the material until it becomes brittle and fails, generally catastrophically,
dumping the animals into the pit.
Secondly, the upper horizontal surface of the aluminum since it was
extruded was linear and flat and thus was slippery so that the animals tended tohave difficulty standing. Sows particularly are not agile and accordingly have
difficulty rising from Iying position. Any slipping of the feet can cause the sow to
fall or to splay which can injure the sow and can crush many piglets. It is wellknown that the crushing of piglets is a significant problem and can dramaticallyreduce the efficiencies of pig production if significant numbers of the piglets are
crushed.
Some attempts were made to overcome these problems. In regard
to the galvanic corrosion, the T-bar slats were electrically insulated from the
underlying concrete structures by providing an insulating plastic strip Iying on top
of the concrete and underneath the T-bar slat. However this attempt was
generally unsuccessful because any electrical connection including through the
steel crate, drinking devices or electrical devices over the life of the product,
which is expected to be several years, caused such galvanic corrosion. Such
electrical connection is difficult to avoid in the presence of the electrically
conductive manure which can bridge insulators. Some attempts were made to
reduce the slipperiness of the horizontal upper surface by attaching abrasive and
welded strips.
Neither of these attempts were of considerable success and
eventually the aluminum T-bar slats were abandoned and no such flooring is
currently manufactured today and is likely that all such flooring previously
installed has become corroded and replaced.
In general, therefore, the use of aluminum for flooring has been
abandoned in view of the above problems and it is believed that those skilled inthe art would reject use of aluminum or similar materials in view of these
problems.
A subsequent approach for providing suitable flooring involved the
provision of supporting beams across the pit and the laying over the supporting
beams of a material known as TenderfootTM which comprises an expanded metal
coated in a plastics material. The expanded metal is steel and the plastics
material reduces corrosion of the steel and provides a more suitable flooring for
the piglets.
A yet further proposal shown for example in the brochure
PolygrateTM of the present assignee comprises a wholly plastics system in which
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the beams are extruded from fiberglass reinforced resin and the flooring covering
those beams is formed from injection molded plastics material.
Both the TenderfootTM flooring and the PolygrateTM flooring have
achieved considerable success and are widely used.
One problem that has however arisen with these materials is that
the flooring is less suitable for location under the sow since the floor is less able
to resist the high level abrasion from the heavy feet of the sow.
Flooring of cast iron grate or panels has therefore been
manufactured for use under the sow. An alternative type of metal flooring which
can resist the abrasion is that of a welded parallel steel rod construction known
as TribarTM.
However these floors are unsuitable for positioning under the
piglets since the piglet should be kept warm and the cooling affect of the thermal
conductivity of the metal and the chimney affect of the air from pit passing
through the openings in the floor tends to cool the piglets at too high a rate. An
attempt has been made to solve this problem by increasing the temperature of
the farrowing crate and this of course causes stress to the sow who is used to atemperature much lower than that is required by the piglets.
The solution currently widely being used is therefore to provide a
plastics flooring or a plastics coated flooring in the area under the piglets and to
provide under the sow a flooring of a cast iron grate. The cast iron grate can be
laid on supporting beams or in some cases is supported on metal webs located at
the edge of the plastics flooring. One example of arrangement of this type is
shown PCT International Application WO95/18525.
However cast iron has significant disadvantages. Cast iron is
difficult to maintain hygienic because it is porous and hence retains moisture
carrying bacteria in the pores and has a surface which has a tendency to retain
moisture and to remain wet again allowing bacteria to remain and multiply on the
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surface. Yet further, the cast iron tends to corrode by developing rust on the
surface. While this corrosion is generally insufficient to cause structural break
down, it does provide further pores and spaces for harbouring moisture and
therefore dangerous bacteria. Despite these disadvantages, the cast iron grate
5 or slat under the sow represents the current standard in the art.
SUMMARY OF THE INVENTION
It is one object of the present invention, therefore, to provide an
improved flooring which overcomes the disadvantages of the prior art.
According to a first aspect of the invention, therefore, there is
10 provided a flooring apparatus for a farrowing containment area for animals, the
containment area having two side edges, a front edge and a rear edge and being
located over a manure containment pit, the apparatus comprising:
a plurality of support members for extending over the manure
containment pit;
a plurality of first panels which are formed from a material selected
from the group consisting of aluminum, magnesium, zinc and alloys thereof;
a plurality of second panels having an upper surface formed of a
plastics material which is electrically non-conductive;
wherein at least some of the first panels have an upper surface
20 which is apertured to allow escape of manure from the animals into the pit;
the first panels being arranged side-by-side to form a first sub-area
of the containment area with at least two remaining sub-areas of the containmentarea being formed by said second panels such that the second panels lie on at
least two sides of said first sub-area such that the two sides of the first sub-area~5 are spaced from the adjacent side edges of the containment area;
the first panels being supported relative to the second panels and
the support members such that the first panels are electrically isolated from any
other electrically conductive element forming part of or associated with the
flooring apparatus to prevent galvanic corrosion thereof.
According to a second aspect of the invention there is provided a
flooring apparatus for a farrowing containment area for animals, the containment5 area having two side edges, a front edge and a rear edge and being located over
a manure containment pit, the apparatus comprising:
a plurality of support members for extending over the manure
containment pit;
a first floor portion which is formed from a material selected from
10 the group consisting of aluminum, magnesium, zinc and alloys thereof;
a second floor portion which is formed of a plastics material which is
electrically non-conductive;
wherein at least part of the first floor portion has an upper surface
which is apertured to allow escape of manure from the animals into the pit;
the first floor portion forming a first sub-area of the containment
area having a front edge, a rear edge and two side edges;
at least two remaining sub-areas of the containment area being
formed by said second floor portion such that the two remaining sub areas each
lie along a respective side edge of said first sub-area such that the two side
edges of the first sub-area are spaced from adjacent side edges of the
containment area;
the support members being formed of an electrically non-conductive
material so as to provide electrical isolation of the first floor portion to prevent
galvanic corrosion thereof.
According to a third aspect of the invention there is provided a
flooring apparatus for a farrowing containment area for animals, the containmentarea having two side edges, a front edge and a rear edge and being located over
a manure containment pit, the apparatus comprising:
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a plurality of support members for extending over the manure
containment pit;
a first floor portion which is formed from a material selected from
the group consisting of aluminum, magnesium, zinc and alloys thereof;
a second floor portion which is formed of a plastics material which is
electrically non-conductive;
wherein at least part of the first floor portion has an upper surface
which is apertured to allow escape of manure from the animals into the pit;
the first floor portion forming a first sub-area of the containment
10 area having a front edge, a rear edge and two side edges;
said second floor portion forming sub areas each of which lies along
a respective one of the front, rear and side edges of said first sub-area such that
the front, rear and side edges of the first sub-area are spaced from adjacent side
edges of the containment area so as to form an island which is spaced from each
15 of the front, rear and side edges of the containment area by the second floorportion and which is electrically isolated from the front, rear and side edges of the
containment area by the second floor portion;
and the first floor portion being supported relative to the second
floor portion and the support members such that the first floor portion is
20 electrically isolated from any other electrically conductive element forming part of
or associated with the flooring apparatus to prevent galvanic corrosion thereof.BRIEF DESCRIPTION OF THE DRAWINGS
One embodiment of the invention will now be described in
conjunction with the accompanying drawings in which:
Figure 1 is a top plan view of a farrowing crate showing the flooring
according to the present invention including first aluminum panels and second
plastics panels.
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Figure 2 is a top plan view showing the flooring in more detail with
the farrowing crate and the aluminum panels removed.
Figure 3 is an isometric view showing one plastic panel of the
flooring mounted on the supporting floor structure.
Figure 4 is a vertical cross sectional view through the flooring
according to the present invention.
Figure 5 is a top plan view of one portion of the flooring structure of
Figure 1 showing part of one aluminum panel and one plastic panel.
Figure 6 is an isometric view of one aluminum panel.
Figure 7 is an enlarged view of one corner of the panel of Figure 6.
Figure 8 is a cross-sectional view along the lines 8-8 of Figure 6.
In the drawings like characters of reference indicate corresponding
parts in the different figures.
DETAILED DESCRIPTION
A farrowing pen is shown in top plan view in Figure 1 and the
flooring for the farrowing pen is shown in more detail in Figure 2. The farrowing
pen is generally indicated at 10 and lies along side and next to adjacent farrowing
pens 10A and 10B. The farrowing pen includes a flooring generally indicated at
11 which overlies a pit 12 arranged between the alleyway 13 on one side and a
rear wall 14 on an opposed side.
The farrowing pen includes a farrowing crate comprises a metal
structure which confines the sow within the farrowing crate. The metal structureis shown only schematically since various different designs are available and
since the structure is well known to one skilled in the art. The farrowing cratethus comprises four metal vertical posts 15, 16, 17 and 18 which are arranged ata front and rear respectively of the farrowing crate. Between the posts 15 and 16
is provided a front gate 19 which can be opened to allow the sow to enter the
alley way when it is required for the sow to be removed from the farrowing crate.
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On the front gate 19 is mounted a feeder 20 which can be accessed by the sow
while in the farrowing crate for taking feed and water as required. The posts are
bolted to the floor 11 by horizontal flanges 21, 22, 23 and 24 respectively which
extend outwardly to one side of the post. Each flange includes a hole by which it
5 can be bolted using a bolt 25 to the flooring 11. The farrowing crate further
includes horizontal rails 26 and 27 extending between respective pairs of the
posts 15, 17, and 16, 18 each along respective side of the area confined for thesow. The rails include plurality of horizontal rails and may include anti-crush bars
and other guide bars which assist in locating the sow, particularly when the sow10 lies down to avoid crushing piglets which may be Iying on either side of the sow.
The farrowing crate further includes a horizontal backup bar 28 which extends
between the two sides of the farrowing crate to prevent the sow from backing up
to the rear wall 14, particularly to prevent the sow from being too close to the rear
wall during the birthing procedure.
The farrowing crate is closed on its sides and front by upstanding
vertical walls 60, 61 which are sufficient merely to confine the piglets. The walls
61 are arranged half way across a panel 30 so that the portions of the farrowingcrate between the central island the side walls 60 is formed by one and a half
panels in width. Of course the second half of the divided panel becomes apart of20 the next adjacent farrowing crate 10A.
Different layouts of the panels can be provided including more
plastics panels in the creep area for the piglets providing an increased area. In
one arrangement, two panels are arranged on one side of the sow area and four
panels on the opposite side. In addition, the sow area can be arranged at an
25 angle to the front and rear edges of the pen.
The flooring system 11 comprises a plurality of flooring panels 30,
31. The flooring panels are rectangular and arranged in an array side by side soas to extend from the rear wall 14 to the alley way 13.
The flooring further includes a support structure for the panels
including a plurality of horizontal beams 33 which are carried in suitable brackets
schematically indicated at 34. The beams extend across the pit and are mounted
at one end on the alley 13 and at the opposed end at the rear wall 14. The
5 brackets 34 can be of various different types depending upon the type of surface
available and whether the weight should be transferred to a vertical surface or to
the base of the pit. The brackets are shown therefore only schematically. The
number of and arrangement of the beams is arranged to be suitable to transfer
the loading from the floor to the support surfaces and preferably therefore the
10 beams are spaced on either side of the sow so as to be provided under the sowarea with the necessity only for at most a single beam supporting the area underthe piglets.
Across the beams is laid a plurality of supporting webs 35 at
longitudinally spaced position along the length of the beams. The webs 35 define15 a vertical flange standing upwardly from the beam and are spaced by the length
of a panel so that front and rear edges 36, 37 of a panel are arranged to lie ontop of a top edge of the respective webs 35. Thus the load from the panel is
transferred to the vertical webs which in turn is transferred to the beams 33 for
supporting the flooring structure defined by the panels above the pit. The webs
20 35 include a base 35A for sitting on the beam and a.stiffening cross-piece 35B.
As shown in Figures 2 and 3, the webs 35 which would pass through the area
under the sow terminate at positions just inside the adjacent beam to form
protruding ends 35C.
The panels 30 are shown in more detail in Figure 3. The panels are
25 generally of a shape and arrangement shown in the above brochure of
"Polygrate" manufactured by the present assignee. Thus the panels are formed
from a molded plastics material to define transverse ribs 38 and 39 at the frontand rear edge respectively of the panel together with the plurality of intervening
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ribs 40 at spaced positions along the length of the panel. In between the ribs are
provided a plurality of longitudinal ribs 41 defining in between them openings 42
through which materials including manure can fall into the pit. The transverse
ribs 38, 39 and 40 provide restrictions to sliding movement in a longitudinal
direction of the panel and the ribs 42 provide restrictions to transverse sliding
movement along the panel. Thus the feet of the animals are prevented from
slipping longitudinally and transversely while the openings allow the passage ofmanure to the pit.
Underneath the various ribs are provided webs one of which is
shown 43 providing structural strength sufficient to support the weight of the
animal and to transfer the weight to the flanges 35.
At the front and rear edges 36 and 37, the panels each include
castelated sections which allow the panels to interleave with the projection at one
edge extending into a recess between two projections at the next adjacent edge
of the next adjacent panel. The projections 44 each include a downwardly
extending lip 45 defining a recess 46 behind the lip into which the top edge of the
flange 35 extends. Thus the top edge of the flange is trapped in the recess 46
and it will be appreciated that the projections of the next adjacent panel includes
similar lips 45 which extend down behind the flange 35 so the flange is trapped in
the area between the overlapping castilated sections of the panels.
At the sides of the panels there are also provided a projection 47 on
one side which interconnects with a recess and receptacle 48 on the opposed
side of the panel. Thus the panels interlock to form the overlying interlocking
structure best shown in Figure 2.
The panels 30 are formed from injection molded plastics material.
The panels 31 are formed by pressure molded from aluminum,
magnesium, zinc, or alloys of those materials. Pressure molding is a known
technique which is similar to that used for injection molding and is intended for
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metals rather than plastic materials. Pressure molding thus uses a permanent
machined mold generally formed from steel. The pressure molding is generally
effected at an elevated pressure, as opposed to simple casting, so that it insures
to form a smooth continuous product with no pores or open spaces.
The use of aluminum, magnesium, zinc or alloys of those materials
insures that the finished product has a finished surface which is relatively smooth
and is free from pores which can collect moisture and harbour bacteria.
Aluminum, magnesium, and zinc also have a very high coeffficient of thermal
conductivity which is significantly higher than that of cast iron for effective cooling
of the sow. Pressure molding of the aluminum also provides a stronger product
which thus allows manufacture of a panel with a higher proportion of voids
between the structural members to allow increased passage of manure and
therefore increased sanitation.
The beams 33 and the webs 35 are formed from a electrically non-
conductive material such as glass fiber reinforced resin. The beams and the
webs or flanges can therefore be formed by the known technique of pultrusion
thus forming a tubular rectangular beam and simple flange or web, both of which
have sufficient strength to accommodate necessary forces.
As shown in Figures 1 and 2, the panels 31 are arranged end to
end and side by side to form an array which is indicated by diagonal lines. The
array as shown is defined by five panels long with each panel having a width
equal to that of the panels 30 and a length preferably double the width so as tospan the length of the opening forming an area which will be of the order of five
feet by two feet. This area is arranged between the rails 26 and 27 of the crate,
that is, in the area under the sow. The area of the panel 31 is however spaced
from the front and rear edges respectively of the flooring system. Thus between
the rear edge of the area is located two panels 30 thus spacing the edges of thepanel 31 from the rear wall 14. Similarly two panels 30 are arranged in front of
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the area of the panels 31 thus again spacing the front edge of the panels from the
alley 13 and from the steel legs of the farrowing crate.
The side rails 26 and 27 are spaced from the flooring so that there
is no connection between the steel side rail 26 and 27 and the flooring. The only
connection of the steel structure of the crate with the flooring is thus provided by
the flanges 21-24 which are bolted to the panels 30.
As the panels 30 are formed from injection molded plastics material,
they are formed of electrically non-conductive material so there is no possibility of
electrical connection between the crate and the area of the flooring defined by the
panels, 31 .
Thus the area of the panels 31 form an island within the
surrounding area defined by the panels 30.
The only objects therefore in contact with the panels 31 are the
edges of the panels 30 which are electrically non-conductive, the webs 35 and
beams 33 all of which are again electrically non-conductive. Thus there is no
possibility of an electrical connection between the panels 31 and the other
electrically conductive material such as the steel of the crate, the concrete and
steel of the alley and walls, water supply pipes, or the feeder or any other object.
The sow therefore is arranged to lie or stand on the area defined by
the panels 31. The feet of the animal generally do not reach to the front and rear
panels in view of the back up bar and the feeder thus locating the animal directly
on the island formed by the panels 31.
The use of the aluminum, magnesium or zinc when pressure
molded has the following advantages;
i) It is non-porous in comparison with cast iron and thus it dries
readily thus reducing the possibility of fostering bacterial growth
by harbouring the bacteria on the sur~ace.
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ii) It provides resistance to wear so that the feet of the animal do
not affect damage or gradual break down of the flooring due to
the abrasion from the feet of the animal.
iii) It provides a very high coefficient of thermal conductivity so that
it cools rapidly. The material therefore tends to remain cooler
than the surrounding plastics material. This cooling effect is
more comfortable for the sow who prefers generally a cooler
environment than the piglets. Also the high thermal conductivity
facilitates the rapid cooling of the floor under the sow when the
sow rises. If the floor remains warm under the sow too long after
the sow stands as in the case with steel or cast iron, this could
cause the piglets to lie on the area warmed by the sow with the
danger of crushing when the sow lies. The piglets are thus
deterred by the cool flooring and the cooling effect of the flooring
from Iying in the area and instead choose to lie in the area of the
plastics flooring where they are warmer and safe from crushing.
iv) It does not rust but instead forms an oxide coating which covers
and protects the surface thus preventing the collection of
materials in the pores of the rust layer.
Turning now to Figures 4 to 8, the details of the panels 31 are
shown which are the first panels formed from aluminum.
The panels are elongate so that the length of the panel is
approximately double the width of the panel so that each panel spans the full
width of the opening under the sow and has a width equal to the width of the
second panels 30 as best shown in Figure 5.
Each panel is integrally molded to form two sides 60 and 61 each of
which forms a vertical flange so as to provide structural strength with the flange
increasing in width toward a central apex 62. Between the sides are two
longitudinal, transversely spaced ribs 63 and 64 which have upper surfaces
substantially at the same height as the sides. Across the panel is defined a
plurality of transverse, longitudinally spaced ribs 65, 66 which are spaced by
approximately the same spacing as the ribs 63 and 64 so as to provide
5 rectangular areas in the ribs. Across these rectangular areas is defined a
plurality of further ribs 67.
The cross section of the raised ribs 63, 64, 65, 66 is as shown in
Figure 8 where the cross section is the same as that indicated at 65. Thus the
ribs of that cross sectional shape converge downwardly and inwardly at a lower
10 section to form a V-shaped portion 68 which diverges outwardly to sides 69 and
70. Between the sides the top surface is arched as indicated at 71. The ribs 67
in the rectangular areas between the raised ribs are of a lower height and have a
top surface 72 which is flat between the sides 69 and 70. Thus the panel forms
pockets in between the raised ribs defined by the top surfaces 72 of the lower
15 ribs so that the pocket can receive the foot of the sow to assist in providing
traction.
Each of the sides 60 and 61 includes a pair of transversely
extending flanges 73 and 74 so that the flanges of one panel can interconnect
with the flanges of the next adjacent panel. Thus the flange 73 is raised that is at
20 the same height as the top of the side wall whereas the flange 74 is at a lower
height for underlying the flange of the next adjacent panel. In this way the
flanges 73 and 74 co-operate to prevent lifting of one panel relative to the next
and to communicate downward forces from one panel to the next.
Each end of each panel is defined by an end wall 75 which forms
25 an end rib similar to the ribs along the side. Each end also includes a flange
section including a horizontal extension portion 76 and a downwardly and
outwardly inclined flange 77. The flange 77, as described hereinafter provides asurface which communicates from the top surface of the panels 31 to the top
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surface of the panel 30 as best shown in Figure 4. At the bottom edge of each
flange 77 is provided a pair of downwardly extending lugs 78 which are spaced
outwardly toward the sides of the panel leading a center section of the edge of
the flange bare from the lugs.
Adjacent each end of the panel, the side walls each include a pair
of web engaging members 80 and 81 each extending outwardly to the respective
side. Each of the members 80 and 81 is arranged for sitting on a respective web
35 and communicating forces from the panel onto the web. The member 81
includes a top flange 90 having a horizontal section Iying along the side wall and
an inclined section which generally follows the shape of the flange 77. The
member 81 defines a raised top surface which lies in the top surface of the panel
and include the flange portion 90 thereof which is co-planar with the flange 77. In
addition each member 81 includes a series of parallel, vertical spaced support
webs 91 each at a right angle to the side of the panel.
The member 80 includes a top surface 82 which is spaced
downwardly from the top surface of the panel by a distance equal to the thickness
of the flange portion 90 of the member 81. The member 80 is defined by a series
of parallel, vertical spaced support webs 92 each at a right angle to the side of
the panel. In this way it will of course be appreciated that the flange 90 of the
next adjacent panel can lie over the top surface 82 of the member 80 so that theflange 90 communicates vertical forces from one panel to the next. The support
webs 91 are arranged to be interleaved with the webs 92 such that both can sit
on the web 35 and communicate forces thereto. Both sets are covered by the
single flange 90 of the member 81 so as to prevent collection of manure. The
side edge of the flange 90 abuts the side edge of the next adjacent panel thus
spacing the side wall of the next adjacent panel from the panel.
In the assembled condition shown in Figures 4 and 5, it will be
noted that the webs 91 and 92 rest upon the top surface of the projecting portion
35C of the webs 35 so as to communicate forces from the panel into the top
surface of the web and thus through to the beams 33. As the panels 31 are
equal in width to the panels 30, the webs 35 are located by the panels 30 by theengagement with the castellated portions and the webs are held vertical by that
5 engagement.
The edge of the flange 77 is arranged to rest upon the top surface
of the panel 30 but is dimensioned so that little or no force is communicated
vertically from the panel 31 to the panels 30 via that flange.
The lugs 78 are arranged so as to engage into a respective one of
10 the openings in the panel 30 as indicated at 85. The lugs thus locate the panel
31 on top of the panel 30 and prevent longitudinal movement of the panel 31
relative to the panel 30 at either end of the panel 31. The lugs 78 can be shaped
particularly at ends of the lugs so as to bite into the ends of the openings 85 in
the panel 30 to provide a locking effect resisting retraction of the lugs from the
15 panel 30.
Thus both the panels 30 and the panels 31 have ribs for assisting in
traction and openings for allowing manure to fall through. The flanges 77 at theends of the panels 31 prevent inhibit the passage of material into the area
underneath the edge of the panel and are located vertically above the beams 33
20 to provide a capping effect.
In an alternative arrangement (not shown) commonly used in
Europe, the flooring is turned at an angle to the front and rear walls so that the
island formed by the panels 31 is arranged substantially diagonal to the area ofthe farrowing crate. The island is itself rectangular and is spaced from the front
25 and rear edges of the farrowing crate by the plastics panels substantially as previously described.
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The flooring can be formed to avoid the use of the pockets in the
upper surface but instead can use the high rib/low rib arrangement known in the
prior art.
Instead of providing both the beams and the webs formed from non-
5 conductive material, one or other may be formed of metal such as steel providedthat the support arrangement for the aluminum flooring panels prevents any
electrical conduction to the metal.
Since various modifications can be made in my invention as herein
above described, and many apparently widely different embodiments of same
10 made within the spirit and scope, it is intended that all matter contained in the
accompanying specification shall be interpreted as illustrative only and not in a
limiting sense.
B
