AU2018256471A1 - Apparatus and process for modifying animal skin by applying cryogenic material - Google Patents

Abstract

A device for applying cryogenic material to the skin of an animal, said device including a pair of jaw members (14) movable between a first engaged position in which the pair of jaw members (14) gather skin (3) at a target zone to which the cryogenic material is to be applied and 5 a second disengaged position in which the pair of jaw members (14) is not in contact with the animal skin, wherein excess or loose skin of the animal is positioned within and above the pair of jaw members (14) when the skin is gathered; means for enabling the pair of jaw members (14) to move between the first and second positions; means for applying the cryogenic material to each jaw member in said pair of jaw members (14), said cryogenic material being applied to a base 10 region only of the gathered skin (3), said base region being in direct contact with the device and positioned and below the excess or loose skin.

Description

ABSTRACT:

A device for applying cryogenic material to the skin of an animal, said device including a pair of jaw members (14) movable between a first engaged position in which the pair of jaw members (14) gather skin (3) at a target zone to which the cryogenic material is to be applied and 5 a second disengaged position in which the pair of jaw members (14) is not in contact with the animal skin, wherein excess or loose skin of the animal is positioned within and above the pair of jaw members (14) when the skin is gathered; means for enabling the pair of jaw members (14) to move between the first and second positions; means for applying the cryogenic material to each jaw member in said pair of jaw members (14), said cryogenic material being applied to a base region only of the gathered skin (3), said base region being in direct contact with the device and positioned and below the excess or loose skin.

2018256471 29 Oct 2018

FIG.

2018256471 29 Oct 2018

APPARATUS AND PROCESS FOR MODIFYING ANIMAL SKIN BY APPLYING CRYOGENIC MATERIAL

Field of the Invention

This invention relates to an apparatus and to a method of modifying the skin of an animal through the application of cryogenic material. More particularly the present invention relates to an apparatus and method of applying cryogenic fluid to an animal, such as a sheep, in a particular location so as to reduce skin folds in that area.

Background of the Invention

Animals such as sheep and in particular Merino sheep and cross-breed Merino sheep are commonly bred in Australia and New Zealand for their high class wool. However a particular 15 trait of these sheep is their loose skin which can result in the presence of skin wrinkles or folds.

The wrinkles or folds particularly occur' in the tail and breech areas at the rear of the sheep. The wrinkles can create a warm and moist protected environment which, given their close proximity to the sheep’s perineum, can be susceptible to soilage by the sheep’s faeces and urine. This can form a suitable breeding ground for female flies to lay their eggs. Once the eggs hatch the larvae 20 infest the sheep’s skin that cause skin necrosis and legions that can become infected and ultimately lead to the death of the animal if left untreated. A common technique that has been used to overcome this problem is mulesing, where four areas of the skin about the tail and back of the hind legs are cut open without anaesthetic in order to remove the skin and remove the wrinkles. However considerable pain is felt by the animals and the area is prone to infection.

The process has been strongly opposed by animal rights groups.

Other methods have involved the use of liquid nitrogen which is applied against the skin of the animal in order to reduce the wrinkling and excess skin. The spray from the nitrogen causes a lot of spillage around the targeted site and liquid nitrogen leaks from some devices used to apply the liquid nitrogen . On some larger sheep, up to 600 gms of nitrogen can be used 30 which is wasteful and expensive. The more nitrogen that is used on non-targetted areas, the more pain that the animal experiences and excess nitrogen spillage can result in scarring around the perineum of the animal.

There are also further problems with the use of clamps or other devices that have liquid nitrogen applied through them in order to be applied to the animal. Firstly the anatomy of the

2018256471 29 Oct 2018 sheep, in particular the hip bone and tail base is curved and some of the clamps do not clamp up the skin effectively around this particular area, leading to spillage on surrounding areas. Other arrangements have had skewed and not parallel sets of clamps which results in more skin being gathered at one end of the jaws or clamps compared to the opposing end and therefore an uneven 5 spread of liquid nitrogen.

The present invention seeks to overcome one or more of the disadvantages by providing a ' method of applying cryogenic material and a device for enabling such application that is less harmful to the animals and also results in less wastage or spillage of the cryogenic fluid. It also aims to make the cryogenic application easier and more time efficient for the operator.

Summary of the Invention

According to a first aspect of the invention, there is provided.a method of applying cryogenic material to the skin of an animal, including the steps of:

gathering skin at a target zone to which the cryogenic material is to be applied using a device, such that excess or loose skin is positioned within and above the device when the skin is gathered;

applying the cryogenic material through the device to a base region only of the gathered skin, said base region being in direct contact with the device and positioned and below ' the excess or loose skin.

The method may further include freezing the excess or loose skin by convection of the liquid and gaseous phase of the cryogenic material.

The excess or loose skin above the device is termed tented skin. The method may further include forming a temperature gradient across the tented skin from the base region of from about -50°C at the base region to about -25°C at the top of tented skin.

The device preferably has a pair of jaw members and the applying step involves distributing the cryogenic material from a source through each jaw member via one or more . apertures to the sldn base region. Each jaw member has a projection or ridge at a lower portion of the jaw member to assist in gathering sldn at the target zone between the jaw members.

According to a second aspect of the invention, there is provided_a device for applying cryogenic material to the skin of an animal, said device including:

a pair of jaw members movable between a first engaged position in which the pair of jaw members gather skin at a target zone to which the cryogenic material is to be applied and a second disengaged position in which the pair of jaw members is not in contact with the animal

2018256471 29 Oct 2018 skin, wherein excess or loose skin of the animal is positioned within and above the pair of jaw members when the skin is gathered;

means for enabling the pair of jaw members to move between the first and second positions;

means for applying the cryogenic material to each jaw member in said pair of jaw members, said cryogenic material being applied to a base region only of the gathered skin, said base region being in direct contact with the device and positioned and below the excess or loose skin. .

Excess or loose skin, termed tented skin, is preferably positioned within and above the device when the skin is gathered, the device is adapted to move forwards and backwards longitudinally along the tented skin, whilst applying the cryogenic material, so that a substantial longitudinal area of skin can be targetted at the target zone after the initial gathering and tenting of skin through the closing action of the jaw members, and to enable a variable depth and length of skin wrinkle to be tagged readily according to differing skin wrinkles of each animal.

The animal is preferably a sheep and each jaw member in said pair of jaw members may be curved to enable the longitudinal movement along the breech, crutch, tail base and along the sides of the tail of the sheep, ensuring the jaw members are in contact with the tentened skin base where a substantial loose skin area is able to be targetted with the cryogenic material.

The means for enabling preferably includes an actuator for controlling movement of a cable, said cable being attached to a framework, such that rods or bolts move within said framework to enable movement of the jaw members.

The device may further include a pair of conduits, in the form of tubes, for delivering the cryogenic material, wherein said conduits extend from a respective jaw member for dispensing the cryogenic material to a connector, which i^ linked to a source of the cryogenic material.

The framework preferably has a series of plate members, some of the plate members having slots therein in which the rods or bolts move. The slots are preferably transverse to a longitudinal direction of the plate members and angled to enable the movement of the jaw members between the first and second positions. Each jaw member may be linked to the framework by an arm and is connected to at least one bolt or rod.

The applying means preferably includes valve means that is controllable to stop or start flow of said cryogenic material to each jaw member. The device may further include control means to control the flow of cryogenic material through said valve means and to control said enabling means.

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According to a third aspect of the invention, there is provided_a pair of jaw members for applying cryogenic material to the skin of an animal, each jaw member in said pair including:

an elongate portion having a first end and a second end;

conduit means for delivering the cryogenic material to a target zone of the skin;

wherein the pair of jaw members together are able to move toward one another to gather sldn in the target zone such that excess or loose skin is positioned above the jaw members and the cryogenic material is applied to a base region only of the gathered skin, said base region being in direct contact with the jaw members and positioned and below the excess or loose sldn.

The conduit means may be a tube located in each jaw member, said tube having apertures through which the cryogenic material moves to be applied to the gathered skin. The pair of jaw meriibers may further include at a lower portion of each jaw member a ridge or projection to assist in gathering said skin at the target zone between the jaw members.

The pair of jaw members may be movable between a first engaged position in which the pair of jaw members gather skin at a target zone to which the cryogenic material is 15 applied and a second disengaged position in which the pair of jaw members is not in contact with the animal skin. The jaw members preferably remain substantially parallel to one another when gathering the skin in the target zone and when the cryogenic material is applied to the base region of the target zone.

Each jaw member preferably further includes a recess in which each tube resides that forms a space around the base region in which the cryogenic material is able to contact the skin of the base region. Each jaw member preferably has a shoulder above its recess, such that in the closed position of the jaws members, a gap exists between the respective shoulder and the skin to enable passage of cryogenic material to contact upper portions of the gathered skin. The pair of jaw members may further include a series of baffles located on each jaw member above said recess and said shoulder for assisting in forcing any surplus cryogenic material downwardly against the targeted skin.

Brief Description of the Drawings

Preferred embodiments of the invention will hereinafter be described, by way of example 30 only, with reference to the accompanying drawings in which:

Figure 1A is a perspective view showing a pair of jaw members applied to the skin of an animal so that a tented portion of the skin is above the pair of jaw members and cryogenic material is applied at a base region of the skin;

Figure IB is a side view showing the tented portion of skin of Figure 1A;

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Figure 1C is a plan view showing a temperature range of various areas of the processed sldn of the animal;

Figure ID is a time lapse view of the processed sldn where a residual scar or scab is shown;

Figure 2A is a perspective view from above of a pair of jaw members shown in a closed position;

Figure 2B is a perspective view of one of the jaw members of Figure 2 A;

Figure 2C is a side view of the pair of jaw members of Figure 2A in a closed position;

Figure 2D is a sectional front perspective view of the pair of jaw members in the closed 10 position;

Figure 2E is a further sectional perspective view at a different angle to that shown in Figure 2D;

Figure 2F is a plan view of the jaw members of Figure 2A shown in the closed position; Figure 2G is a sectional view showing a tented portion of an animal’s sldn clamped between the respective jaw members with the cryogenic material shown in and around the tented portion of the sldn;

Figure 3 shows a series of templates that form a framework in order to move the jaw members between an open position and a closed position;

Figure 4 is a perspective view from above showing a pair of jaws in an open position with apparatus used to actuate the jaw members;

Figure 5 is a underneath view of a frame work that is used to assist in opening and closing the jaw members with the jaw members shown in an open state;

Figure 6 is a view similar to Figure 5 but with the jaw members closed.

Figure 7 is a perspective view from below of the frame work and apparatus of Figure 5 with jaw members in an open state;

Figure 8 is a view similar to Figure 7 but with the jaws in a closed or clamping position; Figure 9A shows a more detailed view from above of a rear portion of the apparatus of Figures 7 and 8;

Figure 9B is a more detailed view of the front portion of the apparatus of Figures 7 and 8;

Figure 10 is a view similar to Figure 7, with the jaw members in an open position and showing an underneath template through which bolts or rods move in order to actuate the jaw members;

Figure 11 is a perspective view from above showing a valve at the side of the apparatus to dispense cryogenic material;

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Figure 12 is a perspective view of the apparatus of Figures 7 and 8 from underneath showing more clearly the valve for supplying the cryogenic material to the jaw members;

Figures 13A and 13B are respectively plan views of the apparatus of Figures 7 and 8 showing the jaw members in two different positions and a corresponding change in movement of 5 a series of bolts in slots of a template that is shown in Figure 6;

Figure 14A is a view of the jaw members about to be applied to the skin of a sheep; and

Figure 14B shows a view of the skin being clamped and the jaw members closed with cryogenic material being applied to the sldn that is clamped.

Detailed Description of the Preferred Embodiments

Referring to Figures 1 A, IB and 1C there is shown a section of the skin of a sheep that has been treated cryogenically where the cryogenic material has been applied through a pair of jaw members 14 around a base region 5 of the skin that results in avascular and cryogenic induced necrosis. Forcing the jaw members 14 together produces a tented portion 3 of skin 15 above the base region 5. Blood supply is subsequently impeded from flowing through the target area 2 of skin and therefore the tented portion 3 and base region 5 undergo a process of necrosis. Outside the target area 2 there is healthy tissue 6 and inside the area 2 (made up of areas 3, 4 and 5) cryogenic cellular lysis has developed. The middle area 4 can have a surface temperature of between -10°C and -20°C, the area 3 that is tented has a surface temperature of about -30°C to 20 25°C, while the base region 5 where the jaw members 14 apply the cryogenic material has a surface temperature of around -50°C. There exists a temperature gradient across the tagetted area.

Figure ID shows in side view the top portion where the cryogenic fluid has been applied suclg that, on either side of that application, the temperature of the skin is around 20°C.

Gradually over time, as seen in the middle and bottom views in Figure ID a scab 8 is formed on top with the skin on both sides contracting around that scab. In the bottom view of Figure ID it is seen that only a small scab 10, which is minimal, remains between the areas of skin 12, during the healing phase and lifts off at 2 to 4 months later resulting in a lineal scar.

In the above cryogenic process, with the resultant variation of targetted tissue temperatures referred to in Figures 1A to ID, apoptosis occurs mostly in the zones where the temperature is -25°C or less and in particular -25°C to -10°C. Skin temperatures that are less than -25°C may not induce a permanent cellular dysfunction or cellular lysis (cell death). Apoptosis is a process of programmed cell death that occurs in multi-cellular· organisms. This is different to necrosis which is a form of dramatic cell death that results from acute cellular injury,

2018256471 29 Oct 2018 as induced by cellular freezing and thawing, for example. Instead apoptosis is a highly regulated and controlled process that gives advantages during an organism’s life cycle.

Cellular injury generally is sufficient enough in conjunction with interruption of blood flow and supply to induce cellular apoptosis within the targetted skin area. The resultant effect is cellular degeneration and cellular lysis within the targetted skin area. The wound healing processes occurring under the targetted skin occur within the epithelialisation process under the dermal skin layer with the resultant surrounding skin contraction and eventual scab or eschar formation and sloughing with a lineal scar forming beneath the eschar or scab, being at the junction of the non-targetted skin zone and the targetted skin zone, that is, at the boundary between the base layer 5 and the non-targetted zone 6 shown in Figure 1C.

Shown in Figures 2A and 2G are perspective viewf of one or two jaw members 14, from the exterior and from the interior, that are used to physically gather and clamp a section of skin that is tented and to which cryogenic liquid (CL), particularly in the form of liquid nitrogen (LN) or liquid air (LA) is applied, at the skin base region 5. The skin is frozen quickly and efficiently 15 without any spillage of the CL onto the surrounding tissue, beneath the jaw members 14 and partially or completely freezes the remainder of the tented skin 3 held above the jaw members

14. The skin is immediately and deeply frozen at the skin contact points 5 (with the jaw members 14) while the tented sldn 3 well above the jaw members 14 is frozen without direct contact with LN or LA. It is frozen instead by latent cold heat convection by direct contact of 20 CL onto the tented and enclosed skin and through apertures in a tube 22 (made from copper) where cold nitrogen gas or air is directed upwards towards the tented skin 3. The whole tented or pinched sldn 3 is frozen and can have varying degrees of freezing. This process effectively acts to target the base periphery 5 of the excess skin so as to minimise CL amount required and contact skin area, when compared to the total skin area targeted. The jaw members 14 can then 25 be moved forward or backward in a longnitudinal manner, freezing a substantial skin length which normally follows the direction of skin wrinkles or excess skin.

Referring to Figures 2A to 2G each of the jaw members 14 are attached to an arm 42 through a series of fingers 21. Each jaw member 14 is generally elongate and curved and has a first end 18 and a second end 19. The curved jaw members 14 mimic the shape of the upper 30 breech and docked tail in a natural position. Recesses 23A and 23B extend generally along the length of a respective jaw member 14. A tube in the form of a copper tube 22 extends through each of a respective recess 23 A or 23B on each jaw member 14 and has up to 12 apertures or more of a diameter of about 0.5mm directed into the overall recess 23 that is formed by the smaller recesses 23 A and 23B when the jaw members are closed. Liquid nitrogen flows through

2018256471 29 Oct 2018 to the end of the copper tube 22 where that end of the recess 23 A and 23B and the tube 22 are blocked off. The tube 22 extends through, portion 27 of the jaw member 14 and through the aperture 20 at the first end 18 and is attached to a supply of liquid nitrogen to be hereinafter described. It is in this area that the liquid nitrogen is applied to the base region 5 of the skin when both jaw members 14 move towards each other and crimp the particular skin area in the base region 5 (see Figure 2G). The jaw members 14 are variable in length and typically have lengths of 75mm, 85mm, 100mm and 120mm to accommodate different sheep ages and sizes. The jaw members 14 are preferably made from stainless steel which acts as a long heat transfer or insulator to minimise the environmental heat conduction.

At a lower portion of the jaw member 14 there is a projection in the form of a ridge 28 that extends substantially along the length of the jaw member 14. The ridge 28 assists in gathering up the skin to be processed so that the pinched skin to be processed is positioned in between the recesses 23 A and 23B of each of the jaw members 14 where the combined recess or space 23 provides the space for the liquid nitrogen to accumulate and freeze the exposed skin segment. Thus only a small circumference or a minimal portion of the complete skin layer to be processed is exposed to the liquid nitrogen, at the base region 5. It is the total whole layer of skin, that is the epidermis and dermis layers 3, that is treated without affecting the subcutaneous tissues 7 (Figure 2G) underneath from being frozen or cryogenically processed. As the jaw members 14 are generally parallel to one another, the gathering of the sldn is performed in a very easy and non-invasive manner and efficiently places the sldn between the two opposing jaw members 14.

At an upper end of the jaw member 14 there is a shoulder 30 which has a face 37. There is a corresponding projection 34 located at the bottom of each jaw member 14 adjacent the ridge 28. This serves to enclose firmly the bottom part of the recess 23 into which the liquid nitrogen 25 is placed and avoids CL leakage. The closing strength of the actuator ensures the enclosed area has sufficient force to inhibit CL leakage under the tented skin amd ensures excess CL is directed upwards. This is more clearly seen in Figure 2E where the pair of jaw members 14 is brought together. The projection 34 has a face 35 that contacts the lower portion of the skin, at the base region 5, that is to be cryogenically processed.

When the jaw members are brought together a pair of projections 34 which have a longitudinal face 35 are in direct contact with each other so that the faces 35 of each jaw member 14 are in full contact. This seals off the lower part of the recess 23 to which the cryogenic liquid is dispersed from the 12 apertures in each of the copper tubes 22. A supply of liquid nitrogen is provided from a separate source and controlled by the user, to be described hereinafter. In that

2018256471 29 Oct 2018 closed position (see Figure 2G) the sldn is pinched or dragged upwardly to form a tented portion where the ridges 28 as previously discussed assist in the gathering of the skin to be processed.

In Figure 2G the presence of the liquid nitrogen is shown in the light blue colour where it completely fills the recess 23. A small gap 38 exists on each side of the skin 3 between a respective face 37 of shoulder 30 of each jaw member 14. This enables the liquid nitrogen to move upwardly through that gap 38 on either side of the skin 3 into a space 40 that is partly filled by baffles 39 (see Figure 2B). This enables further contact with the skin 3 and the liquid nitrogen further up the tented skin 3 to initiate a freezing process. The baffles 39 are distributed on the inside face 41 of the upper member 43 of each jaw member 14 and are distributed generally equally along that inside face 41. When the liquid nitrogen contacts each of the baffles it is generally forced back downwardly due to the angle of the baffle 39 with respect to the inside surface 41. Although the baffles 39 shown in Figure 2B are generally shown as perpendicular to the inside face 41, they can be angled to assist in directing the liquid nitrogen downwardly to remain against the skin of the animal. The baffles 39 are generally between 10 15 and 20 mm in height. .

Figure 3 shows a series of plate members that form the framework of an apparatus 40 that enables the jaw members 14 to move between first and second positions, the first position being an open and separated position and the second position being closed with jaw members 14 acting in parallel on an area of the skin to be processed. The function and operation of each of the plate 20 members in Figure 3 will be described in conjunction with the remaining Figures that show apparatus 40 for actuating the jaw members 14 between the first and second positions.

Figure 4 shows the pair of jaw members 14 in an open and non-engaging position. Each jaw member 14 is connected to a respective arm 42 which connects to a framework or frame structure 60 that incorporates a series of plates and other members 44 to 58 shown in Figure 3.

Specifically the order in which the various plate members are positioned, include a bottom plate member 56 that is connected to plate member 44. Plate member 54 which has angled slots is then positioned above plate member 44. Above plate member 54 is positioned plate member 46 and then plate member 52, which also has angled slots, is placed uppermost above plate member 46. The framework 60 is held together in part by the side plates 48 and 50. The U-shaped member 58 serves as a bridge that goes across the top of the framework 60 and provides a support for a push button actuator 62.

Referring to Figure 4 there is shown the apparatus 40 which is generally hand held by . handle 64 and push button 62 can simultaneously activate the movement of the jaw members 14 (through an actuator) between the first and second positions and activate flow of the cryogenic

2018256471 29 Oct 2018 fluid or liquid nitrogen by operating a solenoid valve adjacent a transportable LN tank (not shown). The jaw members 14 are shown in the spaced apart or disengaged position. A pair of tubes, copper tubes or copper-lined tubes 76 and 78 that terminate in the copper portions 22 supply liquid nitrogen to the jaw members 14. The tubes are heat treated to provide flexibility in the tubes.

The jaw members 14 of apparatus 40 can move forwards and backwards longitudinally along the tented skin, whilst applying the cryogenic liquid so that a larger or substantial longitudinal area of skin can be targetted at the target zone after the initial gathering and tenting of skin through the closing action of the jaw members 14, and to enable the variable amount ( 10 depth) and length of skin wrinkle to be targetted readily according to each sheep differing skin wrinkles.

The curved shape of the jaw members 14 enables the longitudinal movement along the breech, crutch, tail base and along the sides of the tail of the sheep, ensuring the jaw members 14 are in contact with the tented skin base where a substantial loose skin area can be targetted 15 (frozen with the cryogenic liquid), no matter how small or long the skin wrinkles and looseness may be from animal to animal to ensure an end result of plain or wrinkle free breeched sheep.

With reference to Figures 5, 6 and 7 the copper tubes 76 and 78 that respectively lead from the copper tubes 22 in each of the jaw members 14 have a winding path and terminate in a T-connector 75 through which liquid nitrogen is supplied through vacuum steel tube 72. The 20 various curves that are placed in each of the tubes 76 and 78, such as at 77 and 79 provide enough rigidity, flexibility and stability in each of the tubes 76 and 78 so that there is an unimpeded flow of liquid nitrogen through those tubes to the jaw members 14. This is particularly necessary given that the jaw members 14 continually open and close.

Shown in Figure 8 is a view similar to that of Figure 4 except that the jaw members 14 are in the active or engaged position where they abut or are adjacent to one another. A cable 66, which is housed in a protective tube 70, moves inward and outward in order to move the pair of jaw members 14 either towards each other or away from each other. As seen in Figure 4 there are four bolts 81, more clearly seen in Figures 9 A and 9B, that move in respective slots of plate members 44, 46, 52 and 54 and are secured to respective arms 42. The bolts 81 move and rotate within the slots 100 to 114 of plate members 44 and 46 in a transverse fashion, that is transverse to the longitudinal direction or axis of the plate members 44 and 46. For example one bolt member 81 would move within slot 100 of plate member 44 and also slot 108 of plate member 46 laterally, and also move within the angled slot 120 of plate member 52 and angled slot 128 of plate member 54. Similarly another bolt member 81 would move within slot 102 of plate

2018256471 29 Oct 2018 member 44 and slot 110 of plate member 46 laterally, and also move within the angled slot 122 of plate member 52 and 130 of plate member 54. A third bolt 81 would move within slot 104 of plate member 44 and slot 112 of plate member 46 laterally, and also move within the angled slot

116 of plate member 52 and angled slot 124 of plate 54. Finally a fourth bolt member 81 would move within slot 106 of plate 44 and slot 114 of plate member 46 laterally, and also move within the angled slot 118 of plate member 52 and angled slot 126 of plate member 54.

When the cable 66 is withdrawn or pulled outwardly by an actuator, not shown, it brings the jaw members 14 closer together as seen in Figure 8. This is possible through the movement of each of the bolts 81 in their respective slots in plate members 44 and 46 and also through the 10 angled slots of plate members 52 and 54. The slots in plate members 52 and 54 are angled in order to produce the movement of the jaw members 14 towards each other and away from each other. In order to separate the jaw members 14, the actuator moves cable 66 inwardly. The cable 66 is biased through a spring mechanism in compartment 68. A tubular member 73 (Figure 9A) also forms part of the sheath around the cable 66 and moves with the framework 60.

The end of the cable 66 is connected toward the front of the apparatus 40 (as seen in Figure 9B) via a spring and clutch mechanism 71 which enables cable 66 to be displaced away from jaw members 14 when they are closing, and towards the jaw members 14 when they are opening.

The mechanism 71 also enables the jaw members 14 to clamp against varying thicknesses of skin and can therefore be set for different sized sheep. Figures 10 and 11 also show the upper plate 20 member 46 in relatively clear view without the overlay of plate 52. It is seen that the bolts 81 are able to move within their respective slots transversely across the plate member 46.

The cryogenic fluid is supplied through stainless air vacuum steel tube 72 and connects into a leg of T-connector 75. Tube 72 is generally 2 to 4 metres in length and has 3/8 inch diameter. It can act as a small reservoir to store LN temporarily when the LN is not being applied to jaw members 14 or to the animal.

Referring to Figure 12A there is shown the pair of jaw members 14 fractionally open and in Figure 12B fully open. It is to be noted that in Figure 12A the bolts 81 that move in the respective transverse slots 100, 102, 104 and 106 are positioned about mid-way through the slot. In the fully open condition, shown in Figure 12B, the bolts 81 are shown at the ends of the 30 respective transverse slots.

Referring to Figure 13A there is shown a photograph of an in-use application of the apparatus 40 in which the pair of jaw members 14 are about to grip and crimp up the base region 5 of the skin of a sheep. In Figure 13B the jaw members 14 are brought to a closed position in which is crimped skin of the sheep and in particular the tented portion 3 of the skin is shown

2018256471 29 Oct 2018 above the jaw members 14, ready for the application of liquid nitrogen to the target site, being at the base region 5 of the skin.

In operation an operator can hold the apparatus 40 through handle 64 and activate the button 62 to bring the jaw members 14 together at a target site while simultaneously enabling the 5 supply of the liquid nitrogen to that target site. Only a few seconds is needed to apply liquid nitrogen to the target skin site. Typically, the LN is applied to the skin area for between 0.5 and 3 seconds, more preferably 1 to 2 seconds. Each sheep takes about 10 to 15 seconds to treat with the LN material.

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Claims (22)

1. 2018256471 29 Oct 2018

   CLAIMS:

   1. A method of applying cryogenic material to the skin of an animal, including the steps of: gathering skin at a target zone to which the cryogenic material is to be applied using a device, such that excess or loose skin is positioned within and above the device when the skin is

   5 gathered;

   applying the cryogenic material through the device to a base region only of the gathered skin, said base region being in direct contact with the device and positioned and below the excess or loose skin.
2. 2. A method according to claim 1 further including freezing the excess or loose skin by

   10 convection of the liquid and gaseous phase of the cryogenic material.
3. 3. A method according to claim 1 or claim 2 wherein the excess or loose skin above the device is termed tented skin, the method further including forming a temperature gradient across the tented skin from the base region of from about -50°C at the base region to about -25°C at the top of tented skin.
4. 4. A method according to any one of the preceding claims wherein the device has a pair of

   15 jaw members and the applying step involves distributing the cryogenic material from a source through each jaw member via one or more apertures to the skin base region.
5. 5. A method according to claim 4 wherein each jaw member has a projection or ridge at a lower portion of the jaw member to assist in gathering skin at the target zone between the jaw members.

   20
6. 6. A device for applying cryogenic material to the skin of an animal, said device including:

   a pair of jaw members movable between a first engaged position in which the pair of jaw members gather skin at a target zone to which the cryogenic material is to be applied and a second disengaged position in which the pair of jaw members is not in contact with the animal sldn, wherein excess or loose skin of the animal is positioned within and above the pair of jaw

   25 members when the skin is gathered;

   means for enabling the pair of jaw members to move between the first and second positions;

   means for applying the cryogenic material to each jaw member in said pair of jaw members, said cryogenic material being applied to a base region only of the gathered skin, said

   30 base region being in direct contact with the device and positioned and below the excess or loose skin..
7. 7. A device according to claim 6 such that excess or loose skin, termed tented skin, is positioned within and above the device when the skin is gathered, the device is adapted to move forwards and backwards longitudinally along the tented skin, whilst applying the cryogenic

   2018256471 29 Oct 2018 material, so that a substantial longitudinal area of skin can be targetted at the target zone after the initial gathering and tenting of skin through the closing action of the jaw members, and to enable a variable depth and length of skin wrinkle to be tagged readily according to differing skin wrinkles of each animal.

   5 8. A device according to claim 7 wherein said animal is a sheep and each jaw member in said pair of jaw members is curved to enable the longitudinal movement along the breech, crutch, tail base and along the sides of the tail of the sheep, ensuring the jaw members are in contact with the tentened skin base where a substantial loose skin area is able to be targetted with the cryogenic material.
8. 10 9. A device according to claim 8 wherein the means for enabling includes an actuator for controlling movement of a cable, said cable being attached to a framework, such that rods or bolts move within said framework to enable movement of the jaw members.

   10. A device according to claim 8 further including a pair of conduits, in the form of tubes, for delivering the cryogenic material, wherein said conduits extend from a respective jaw

   15 member for dispensing the cryogenic material to a connector, which is linked to a source of the cryogenic material.
9. 11. A device according to claim 9 wherein the framework has a series of plate members, some of the plate members having slots therein in which the rods or bolts move.
10. 12. A device according to claim 11 wherein the slots are transverse to a longitudinal direction

    20 of the plate members and angled to enable the movement of the jaw members between the first and second positions.
11. 13. A device according to claim 12 wherein each jaw member is linked to the framework by an arm and is connected to at least one bolt or rod.
12. 14. A device according to any one of claims 6 to 13 wherein the applying mjans includes

    25 valve means that is controllable to stop or start flow of said cryogenic material to each jaw member.
13. 15. A device according to claim 14 further including control means to control the flow of cryogenic material through said valve means and to control said enabling means.
14. 16. A pair of jaw members for applying cryogenic material to the skin of an animal, each jaw

    30 member in said pair including:

    an elongate portion having a first end and a second end;

    conduit means for delivering the cryogenic material to a target zone of the skin;

    wherein the pair of jaw members together are able to move toward one another to gather skin in the target zone such that excess or loose skin is positioned above the jaw members and

    2018256471 29 Oct 2018 the cryogenic material is applied to a base region only of the gathered skin, said base region being in direct contact with the jaw members and positioned and below the excess or loose skin.
15. 17. A pair of jaw members according to claim 16 wherein the conduit means is a tube located in each jaw member, said tube having apertures through which the cryogenic material moves to

    5 be applied to the gathered sldn.
16. 18. · A pair of jaw members according to claim 17 further including at a lower portion of each jaw member a ridge or projection to assist in gathering said skin at the target zone between the jaw members.
17. 19. A pair of jaw members according to any one of claims 16 to 18 wherein said pair of jaw

    10 members is movable between a first engaged position in which the pair of jaw members gather skin at a target zone to which the cryogenic material is applied and a second disengaged position in which the pair of jaw members is not in contact with the animal skin.
18. 20. A pair of jaw members according to claim 19 wherein the jaw members remain substantially parallel to one another when gathering the skin in the target zone and when the

    15 cryogenic material is applied to the base region of the target zone.
19. 21. A pair of j aw members according to claim 20 wherein each j aw member further includes a recess in which each tube resides that forms a space around the base region in which the cryogenic material is able to contact the skin of the base region.
20. 22. A pair of jaw members according to claim 21 wherein each jaw member has a shoulder

    20 above its recess, such that in the closed position of the jaws members, a gap exists between the respective shoulder and the skin to enable passage of cryogenic material to contact upper portions of the gathered skin.
21. 23. A pair of jaw members according to claim 22 further including a series of baffles located on each jaw member above said recess and said shoulder for assisting in forcing any surplus
22. 25 cryogenic material downwardly against the targeted skin.

    2018256471 29 Oct 2018