Flooring system for farrowing pen

Flooring for a farrowing crate particularly for pigs is formed of beams and support flanges which are manufactured of glass fiber reinforced resin so as to be electrically insulating. The beams span a pit for receiving manure. On top of the supporting structure is provided a flooring formed of a plurality of rectangular panels or tiles arranged side to side and edge to edge to form an array of the panels. An area under the sow is defined of pressure molded aluminum panels or extruded and welded aluminum bars and an area fully surrounding an island of aluminum panels is defined by panels of injection molded plastics which are again non-conductive. The steel structure of the farrowing crate is bolted to the plastics panels at positions forwardly and rearwardly of the island of aluminum panels. Thus the aluminum panels are electrically insulated by the plastic panels and the non-conductive support beams from any electrically conductive element within the farrowing crate to prevent galvanic corrosion of the aluminum panels. Where the aluminum beams are extruded they can be hollow to allow the passage of a cooling fluid to cool the sow. A heat pump is used to transfer the heat from the sow to the piglets on the plastic panels.

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 lying in the side areas and 
thus crushing the piglets. The crate and flooring system allows the sow to 
stand so 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 surrounding concrete 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 harbored in the flooring and pen system. 
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 web of 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 the liquid 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 to have difficulty standing. Sows particularly are not agile and 
accordingly have difficulty rising from lying 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 well known that the crushing of piglets 
is a significant problem and can dramatically reduce 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 
lying 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 a published article in the paper "Feld und Wald" No. 16 of 16th Apr. 
1976 is disclosed the use of elongate aluminum panels which span the space 
across the pit and are therefore supported at respective ends on the sides 
of the pit. This disclosure is similar to the aluminum T bars and is 
around the same time as the use of the T-Bar system. This does not mention 
corrosion and does not seem to have lead to wide scale adoption of this 
technique. 
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 in the 
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 "Tenderfoot" 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 "Polygrate" of the 
present assignee comprises a wholly plastics system in which the beams are 
extruded from fiberglass reinforced resin and the flooring covering those 
beams is formed from injection molded plastics material. 
Both the Tenderfoot flooring and the Polygrate 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 
"Tribar". 
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 a temperature 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 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 or slat under the sow represents the 
current standard in the art. 
Another arrangement is disclosed in DE G9320652 assigned to Ikadan Systems 
of Denmark published in 1995 which corresponds to U.S. Pat. No. 5,687,534 
issued 18th Nov. 1997. This discloses a steel beam system with the beams 
extending across the manure pit to support the flooring. The flooring 
includes cast iron gratings which are arranged to be supported by the 
beams. In order to support the cast iron gratings in a manner which is 
more suitable, the applicant provides a plurality of hanger members which 
are formed of plastics material. These hangers are provided for structural 
reasons and are not in any way concerned with electrical insulation. 
Yet another arrangement uses PVC pipes for supporting the sow and attempts 
to cool the sow by communicating heat from water in the pipes to the 
drinking water. This arrangement was commercially unacceptable as the 
flooring could not accommodate the hard wearing effect of the feet of the 
animal. This arrangement is shown in a brochure by INSERT. 
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 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 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; 
at least part of the first floor portion having 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. 
Preferably the second floor portion includes at least one additional sub 
area each arranged along at least one of the front and rear edges of the 
first sub area. 
Preferably the second floor portion is molded from a plastics material. 
Preferably the first and second floor portions are formed from panels which 
are rectangular and of the same width. 
Preferably the panels of the first floor portion have upper surfaces 
thereof at a raised height relative to the panels of the second floor 
portion. 
Preferably the first panels each have an edge flange inclined downwardly 
onto the upper surface of the second panels, the flange having downwardly 
extending tabs for engaging into openings in the second panels to 
interlock at edges thereof to form an integral floor. 
Preferably the support members include a plurality of beams and a plurality 
of cross webs arranged in parallel, spaced relation substantially at right 
angles to the beams with the first and second panels being supported on 
the cross webs. 
Preferably the first panels each include at each end a cooperating pair of 
interlocking web engagement members extending outwardly to a respective 
side of the panel for engaging a top of a respective one of the cross webs 
for communicating weight from the first panels to the cross webs. 
According to a second aspect of the invention there is 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 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; 
at least part of the first floor portion having 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; 
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 of the front, rear and side edges of the 
containment area by the second floor portion 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 
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 third aspect of the invention there is 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 first floor portion which is formed from a material selected from the 
group consisting of aluminum, magnesium, zinc and alloys thereof; 
at least part of the first floor portion having 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; 
the first floor portion comprising at least one rigid panel defined by a 
plurality of cross beams at spaced positions along a length of the panel 
and a plurality of extruded members extending longitudinally of the panel 
at right angles to the cross beams and attached thereto, the extruded 
members being parallel and spaced each from the next to leave openings 
therebetween, the cross beams and the extruded members being formed from 
said material; 
a second floor portion which is formed of a plastics material which is 
electrically non-conductive; 
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. 
Preferably said at least one panel comprises a single panel defining the 
whole of the first floor portion. 
Preferably said extruded members are welded to the cross beams. 
Preferably the extruded members are generally triangular in cross-section 
with a generally horizontal upper surface and two sides converging 
downwardly and inwardly to a bottom apex underneath the top surface. 
Preferably the extruded members are arranged alternately such that 
alternate ones thereof have an upper surface thereof at a raised height 
and a lowered height. 
Preferably the cross beams each comprise a flat web standing in a vertical 
plane with a series of recesses in an upper edge thereof at spaced 
positions thereacross such that each extruded member is received in a 
respective one of the recesses. 
Preferably the recesses are arranged such that an upper surface of each 
extruded member is no higher than the upper edge of the web. 
Preferably there is provided a welded bead across the upper edge of the web 
and over the upper surface of each extruded member in turn. 
Preferably the extruded members are hollow so define a tubular duct along 
the length thereof. 
Preferably there is provided a source of cooling fluid for passing along 
the tubular ducts of the extruded members for cooling the first floor 
portion. 
Preferably the apparatus includes a heat pump for extracting heat from the 
cooling fluid for cooling the fluid and a heat transfer member for 
receiving the heat from the heat pump for transferring the heat to the 
second floor portion. 
Preferably the apparatus Includes a flat plate covering a part of the first 
floor portion and attached thereto. 
According to a fourth aspect of the invention there is 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 first floor portion forming a first sub-area of the containment area; 
the first floor portion comprising at least one rigid panel defined by a 
plurality of cross beams at spaced positions along a length of the panel 
and a plurality of elongate tubular members extending longitudinally of 
the panel at right angles to the cross beams and attached thereto, the 
elongate tubular members being parallel and spaced each from the next to 
leave openings therebetween; 
a second floor portion defining at least two remaining sub-areas of the 
containment area 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 elongate tubular members being hollow so as to define a tubular duct 
along the length thereof. 
a source of cooling fluid for passing along the tubular ducts of the 
extruded members for cooling the first floor portion. 
a heat pump for extracting heat from the cooling fluid for cooling the 
fluid; 
and a heat transfer member for receiving the heat from the heat pump for 
transferring the heat to the second floor portion.

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 FIG. 1 and the flooring for 
the farrowing pen is shown in more detail in FIG. 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 structure is 
shown only schematically since various different designs are available and 
since the structure is well known to one skilled in the art. The farrowing 
crate thus comprises four metal vertical posts 15, 16, 17 and 18 which are 
arranged at a 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. 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 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 the sow. 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 sow lies down to avoid crushing piglets 
which may be lying 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 
farrowing crate 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 of 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 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 so 
as 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 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 beams are spaced on either 
side of the sow so as to be provided under the sow area with the necessity 
only for at most a single beam supporting the area under the 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 
define 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 on top 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 35 include a base 35A for sitting on 
the beam and a stiffening cross-piece 35B. As shown in FIGS. 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 FIG. 3. The panels are 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 front 
and rear edge respectively of the panel together with the plurality of 
intervening 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 of manure 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 FIG. 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 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 coefficient 
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 FIGS. 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 to span 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 the panel 31 from the rear wall 14. 
Similarly two panels 30 are arranged in front of 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 nonconductive. 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 surface. 
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 lying 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 FIGS. 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 FIG. 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 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 FIG. 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 
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 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 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 cooperate 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 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 a surface which communicates from the top surface of the panels 
31 to the top surface of the panel 30 as best shown In FIG. 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 
centre 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 lying 
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 coplanar 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 the flange 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 FIGS. 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 the engagement with the castellated portions and the webs are held 
vertical by that 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 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 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 the ends 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 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 of the farrowing crate. The island is itself rectangular and is 
spaced from the front and rear edges of the farrowing crate by the 
plastics panels substantially as previously described. 
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 nonconductive 
material, one or other may be formed of metal such as steel provided that 
the support arrangement for the aluminum flooring panels prevents any 
electrical conduction to the metal. 
Turning now to FIGS. 9 through 12, there is shown a modified arrangement 
which provides two further advantages. 
Firstly the first flooring section forming the central island is formed as 
a single panel defined by a plurality of longitudinally extending extruded 
support members and a plurality of transverse support beams to which the 
extruded members are welded. Instead of forming the island therefore from 
cast material, the island can be formed more cheaply from a combination of 
extruded bars or support members and transverse beams to which the 
extruded bars are welded. Preferably the panel is formed in a single piece 
since this is the most efficient manner for manufacture. However the panel 
can also be formed in two or more pieces separated transversely. In 
situations where the underlying support beams provide a degree of flex 
which is greater than that of the welded panel, it may be desirable to 
divide the panel into two portions so that the two portions can flex to a 
degree matching that of the support beams. 
The extruded bars can be solid as shown in FIG. 10. As an alternative, the 
extruded bars can be hollow defining a longitudinally extending tubular 
duct. As the extruded bars are manufactured by extrusion, the 
cross-sectional shape can be simply tailored to requirements and therefore 
hollow tube can readily be manufactured. 
The hollow tube can provide a conduit for cooling liquid so as to assist in 
maintaining the sow cooled. The cooling fluid can be cooled by a heat pump 
which extracts heat from the cooling fluid and transfers that heat to a 
radiator system for adding heat to the piglets. 
Turning therefore to the details showing in the Figures, the panels 31 are 
substantially as previously described and cooperate with the remainder of 
the farrowing crate in the manner previously described particularly in 
regard to FIG. 1. However the individual panels 31 of FIG. 1 are replaced 
by a single panel 31A which lies over the opening defined in the area 
where the panels 31 are omitted. 
The single panel 31A includes two side support flanges 101 and 102 and two 
end support flanges 103 and 104. The panel further includes a plurality of 
longitudinally extending parallel extruded bars 105 which are 
interconnected by transverse support beams 106. The structure formed by 
these elements is welded to form a rigid structure which is laid over the 
opening and spans the opening. All of the elements of the welded panel are 
formed from one of the above mentioned selected materials and preferably 
aluminium. 
Thus as shown in FIG. 10, the panels 30 sit on the floor support joists 
107. These joists are the type different from the joists 33 of the 
previous embodiment in that the joists include an upstanding flange 108 
which extends into the receptacle 109 at the edge of the panel 30. The 
flange 108 thus in effect matches the flange 35 of the previous 
embodiment. 
The panels 30 thus define an upper surface 110 at the receptacle 109 so 
that the flanges 101 and 102 lie over the upper surface and are supported 
thereby. 
The cross-beams 106 are formed so that each defines an upstanding vertical 
web with a bottom edge 111 and a top edge 112. The top edge is cut to form 
a series of notches 113 and 114. The notches 113 are deeper than the 
notches 114. The notches are generally triangular in shape converging 
inwardly and downwardly to a bottom apex 115. 
The extruded bars 105 are shaped to define a generally flat top surface 116 
and two sides 117 and 118 converging inwardly and downwardly to the bottom 
apex 115. The notches 113 are cut so as to match the shape of the bar so 
as to receive the respective bar substantially wholly within the 
respective notch so that the upper surface 116 is aligned with the upper 
surface 112. The notches 114 are shallower and therefore the upper surface 
116 of the bars in those notches stands proud of the upper surface 112. 
Across the top surface 112 of each beam 106 is applied a bead 120 of weld 
which thus attaches to the upper surface 122 and across the top surface 
116 of each of the bars. The bead thus rigidly attaches the bars to the 
beams 106 to form a rigid structure. 
The flanges 101 and 102 are welded to end portions 121 of the beams 106 and 
have a width sufficient to extend outward beyond the end 122 of the beam 
to engage over the edge of the panel 30. 
In the embodiment as illustrated, the bars in the shallower notches stand 
proud of the surface 112. It is also possible that the shallower notches 
provide an arrangement in which the bars are flush with the surface 112 
and the deeper notches recess the upper surface from the surface 112. 
The flanges 103 and 104 are welded to the end beam 106 and also are mitred 
with welded connections to edges of the flanges 101 and 102 so the 
surrounding flange structure is rigid and rigidly attached to the 
remainder of the panel. 
The use of extrusion for manufacturing the bars allows the bars to be 
manufactured relatively cheaply using inexpensive tooling. The cutting of 
the transverse beams can be also be effected relatively simply and the 
welding is effected in a lay-up jig arrangement so the complete panel can 
be manufactured relatively simply and inexpensively. This avoids the use 
of expensive tooling necessary for casting individual panels since that 
tooling has a relatively limited life. Avoiding expensive tooling also 
allows modifications to be adopted relatively quickly. 
In FIGS. 11 and 12, the bars are modified from the solid bars of FIG. 10 to 
define a hollow interior 125 forming a tubular duct along the length of 
each bar. In this embodiment, two transverse beams 126 and 127 are 
arranged adjacent the ends of the bars 105 and underlying the respective 
flanges 103 and 104. A base plate 128 closes a hollow interior 129 defined 
by the beams 126 and 127 so as to form a header communicating with the 
hollow interior of each of the bars 105. A first header 130 is provided at 
the flange 103 and a second header 131 is provided at the flange 104. 
In this embodiment an additional plate 132 is attached over the top of the 
bars adjacent the end flange 104 which is the front of the farrowing pen 
to protect the feet of the animal. 
The headers 130 and 131 are connected to a source of cooling fluid defined 
by a heat pump 140 so that fluid from the heat pump passes through the 
header 131, along the tubular ducts 125, from the header 128 and back to 
the heat pump 140. This cooling fluid thus acts to cool the bars to 
maintain the bars at a cooler temperature than the surrounding area to 
provide more comfort to the sow. 
The use aluminium extruded bars allows the bars to be readily manufactured 
in the tubular hollow manner while maintaining sufficient strength to 
provide support for the sow. 
The cooling of the central panel under the sow reduces the tendency of the 
piglets to lie in this area since they are made uncomfortable by the 
temperature so they are encouraged to move away from this area thus 
reducing possibility of crushing as the sow lies down. 
The heat extracted from the cooling fluid can be communicated to a radiator 
141 placed on the panels 30. The radiator comprises a flat radiating plate 
142 on the underside of which is provided a radiator coil 143 which is 
supplied heated liquid from the heat pump 140. The coil 143 is provided on 
top of the panels and underneath a support plate in order to reduce the 
tendency of the heated air to rise which could otherwise form a chimney 
effect through the panels 30 drawing 
The use of aluminium as a material for the central panel therefore has the 
advantages previously described and utilises the electrical isolation 
system previously described. Yet further the panel can be manufactured 
relatively simply from extruded bars which allows a cooling effect to be 
utilised by passing the cooling fluid through the bars. 
The flanges 101, 102, 103 and 104 are flat in the embodiment shown. However 
the flanges can be inclined outwardly and downwardly to lift the top 
surface of the central panel to a raised height above the top surface of 
the plastic panels if required. 
Since various modifications can be made in my invention as herein above 
described, and many apparently widely different embodiments of same 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.