CROSS-REFERENCE TO RELATED APPLICATIONS

This is a Divisional application of prior application Ser. No. 09/126,685 filed Jul. 30, 1998, now U.S. Pat. No. 5,997,553 which is a divisional application of Ser. No. 08/938,326 filed Sep. 26, 1997 (issued as U.S. Pat. No. 5,843,095), which is a continuation in part of application Ser. No. 08/414,638 (issued as U.S. Pat. No. 5,681,329) filed Apr. 3, 1995. This application is also a divisional of Ser. No. 07/807,727 (issued Aug. 17, 1993 as U.S. Pat. No. 5,236,434) filed Dec. 16, 1991. The entire disclosures of the prior applications are considered to be part of the disclosure of the accompanying application and are hereby incorporated by reference.

FIELD OF THE INVENTION

This invention relates in general to methods and apparatuses for raising meat producing cattle to achieve superior growth of such animals and, in particular, relates to a method and apparatus for weaning, feeding and castration of cattle to improve the profitability of a cattle raising operation.

BACKGROUND OF THE INVENTION

A common method for the removal of a body part is ligation. Ligation is a process in which a band or cord is fastened to the body part to be removed in order to constrict it, thus cutting off the supply of blood and systemic support. The body part thereafter atrophies and drops away from the body. Ligation has been used for many purposes including castration and the removal of horns, tails or other body parts from animals.

Ligation has a number of advantages over surgical procedures for such applications. First, ligation has a safety advantage in that the animal normally does not become susceptible to infection. For example, in the case of castration of bulls, a period of about two weeks to a month typically passes between the time that the ligature is attached to the scrotum and the time that the scrotum drops off. During this time the area adjacent the ligature heals, thus reducing the likelihood of infection. Another advantage of ligation is that ligation can be performed quickly by non-expert personnel, thereby reducing costs. In addition, when the ligature is sufficiently tight, ligation can generally be performed with little stress on the animal because the body part numbs quickly after the blood supply is cut off.

According to one conventional method of ligation, an endless loop of elastic band is stretched to encircle a body part and is used to cut off the blood supply to the body part to be removed. Because the band is endless, the band must be stretched to open it up a sufficient amount so that it can be positioned by passing the band loop over the body part as disclosed in U.S. Pat. No. 4,527,179. This conventional method has the disadvantage that it is difficult to attach the ligature band such that it is sufficiently tight. For example, when an endless band is used to castrate bulls, the band must be stretched to pass over the scrotal sac and its contents and then released to engage the sac at the desired position. The tightness of the band when positioned is therefore limited by the band's elasticity. In addition, because an endless ligature band generally cannot be tightened, the size of the band loop can only be roughly matched to a particular application. That is, the band is usually selected from a limited number of discrete band sizes. Because of the difficulty in tightening conventional endless bands, such bands may fail to sufficiently cut off the blood supply resulting in prolonged stress to the animal and an increased likelihood of swelling and/or infection. In addition, there is a greater chance that the animal will intentionally or unintentionally displace a loose band.

Another ligation method is disclosed in U.S. Pat. No. 4,691,704. A loop of a ligature elastomeric band is formed around the body part to be ligated, and then an end portion of the band is attached to a tightening rod. The tightening rod can then be retracted in a substantially linear fashion by successive pulls on a trigger mechanism, thereby tightening the loop. However, the process of tightening the loop through successive pulls on the trigger mechanism is time consuming and the animal must therefore be restrained for a longer period of time. In addition, the tension which can be imparted to the band, and the tightness of the loop, are limited by the hand strength of the user. Moreover, relatively large frictional and abrasive forces are exerted on the band where the band is attached to the tightening rod, thereby increasing the likelihood of damage to the elastomeric material causing breakage before the desired tension is achieved. Furthermore, the attachment of the end portions of the band can be time consuming and thus impede the speed at which cattle or other livestock can be processed. Additionally, due to the design of the ligature tool, an operator is limited in the extent a band can be tightened. Once an operator has fully retracted the tightening rod, the loop's tightness cannot be increased.

The inability to achieve relatively quick and complete occlusion of both venous and arterial pressure within the body part being ligated may result in the venous pressure alone being shut off, thereby permitting the stronger arterial pressure to fill the body part with blood. This, in turn, can lead to swelling of the body part and failure of the ligation process, causing consequential pain to the animal.

Accordingly, it would be advantageous to provide a ligation tool that can attain a given tension on any elastomeric band without being limited by tool design. It would be further advantageous for the ligation tool to provide an indicator of the tension in the band so that an operator can be assured that an effective amount of ligating tension has been placed on the band.

Additionally, the cattle raising industry has experienced decreased profits due to an imbalance between meat prices and the overhead involved in the raising of cattle. This is at least in part due to conventional cattle raising practices where young male calves are castrated and branded at an early age, thus depriving such calves of natural hormones that promote growth. Moreover, cattle can become highly stressed at various periods, causing slow growth, loss in weight and/or a lower quality or grade of meat. For example, cattle may become especially stressed when the cattle experience any of the following events: being abruptly weaned, provided with unfamiliar surroundings or feed, and castrated, especially in a later period of their life (e.g., at six months to around one year old).

Moreover, cattle raising overhead has increased due to the practice of early castration of bulls followed by subsequent provision to such castrated animals (i.e., steers) with hormone supplements to increase growth and promote weight gain. Thus, not only do such steers experience a reduced growth in comparison with (uncastrated) bulls, but the ratio of lean meat to fat is decreased, thereby providing a lower quality of meat.

Accordingly, it would be advantageous to provide a cattle raising management program that reduces the stress in cattle related to the above-mentioned events and also to reduce or eliminate the need for hormone supplements to be provided to steers. Further, it would also be advantageous to provide a cattle raising management program that decreases the cattle raising overhead by accelerating the growth of cattle so that the age by which cattle can be profitably slaughtered is decreased.

SUMMARY OF THE INVENTION

The present invention discloses a method and apparatus for ligation which avoids or alleviates the problems discussed above. The present invention allows a ligature band to be tightly attached to an animal body part thereby reducing the likelihood of swelling, infection and/or prolonged stress to the animal. The present invention also allows the band to be tightened quickly thereby reducing the length of time that the animal must be restrained.

According to one aspect of the present invention, a method and apparatus for ligation is provided. The method includes the steps of forming a loop about the body part with a band of ligature material and winding the band to tighten the loop. Preferably, the band is tightened by securing the band to a spool and then rotating the spool to wind the band. After the loop is tightened, the loop can be secured by crimping a grommet so that the band is secured therein.

A separate aspect of the present invention relates to a method and apparatus for using a preformed endless loop to sever animal parts. Use of an endless ligation loop eliminates the conventional practice of using a linear length of banding material to form a loop around a body part and avoids the subsequent need to attach the respective ends of the band to a means for pulling the band to tighten the loop. Furthermore, use of a pre-formed loop (i.e., formed prior to insertion of any band material into a ligation device) eliminates the need for cumbersome lengths of ligation material used in conventional ligation operations and enables an operator to slip pre-formed loops around a belt, into a carrying case, etc., thus facilitating easy access to such loops when performing multiple ligation procedures. Moreover, use of pre-formed loops having pre-attached grommets ensures that a loop is never tightened without a grommet first being in place. The likelihood of losing the grommet is also reduced and the preformed endless loop may be inserted in the tool and attached to a means for pulling in a more efficient manner. The pre-formed loop having a grommet pre-attached to the loop, (preferably to form an hour-glass shaped loop) is useful not only with the winding tool disclosed herein, but is also useful with prior art devices, such as the “caulking gun-type” device described by Wadsworth, U.S. Pat. No. 4,691,704.

Moreover, it is an aspect of the present invention that such pre-formed endless loops may be formed from a length of elastomeric band without the use of additional components for tying the ends of the length together. In particular, it has been discovered by the inventor that by providing a passageway through a thickness of the elastomeric band (e.g., by puncturing) and expanding the passageway sufficiently, so that one of the band ends can be inserted therethrough, that when the passageway is allowed to constrict about the inserted end, a loop is obtained that can be effectively used by the ligation tool of the present invention.

A tool constructed in accordance with an embodiment of the present invention includes a receiving device for receiving a band of ligature material, wherein the band forms a loop external to the receiving device. A winding assembly is interconnected to the receiving device such that the loop is tightened by winding the band.

Preferably, the winding assembly includes a spool that facilitates the securing of a band thereabout as the spool is rotated. A ratchet mechanism can be employed to provide for one way rotation of the spool. In one embodiment, the tool is operated by pneumatic or electrical motors or by power tools which function to wind the band around the spool to achieve a desired loop tightness or tension. In a related embodiment, the motor or power source used to wind the tool is recessed within the handle portion of the tool and engages a worm gear or other similar mechanism to rotate the winding spool. The tightness of the loop can be modified by adjusting either the pneumatic/electrical winding device so that winding of ligature material ceases at a predetermined tension, or by providing a clutch mechanism on the tool itself. The winding assembly may rotate in a direction perpendicular to the longitudinal axis of the tool effectively shortening the endless loop and applying pressure around the selected body part of the animal.

In another embodiment of the ligation tool of the present invention, the tool is provided with a tensioning indicator that indicates the tension applied to an elastomeric loop during a ligation procedure. Thus an operator of this embodiment of the tool can be assured that an effective ligation tension is provided to the loop. Moreover, in one embodiment of the tool, the tension indicator is provided by a compressible tool body, wherein the amount of compression indicates a corresponding tension on the loop or band. The compressible tool body may be provided by telescoping tool body segment, wherein one tool body segment slidably moves or compresses as an insert within an outer tool body segment. Further, a compression spring may be used to provide resistance against compression forces urging the inserted body segment further into the outer tool body segment. Thus, by calibrating the extent of compression of the compression spring for various degrees of compressive force, a loop tension indicator can be provided as one or more markings on either the inner or the outer tool body segment.

In a preferred embodiment, the tool includes a lever which is biased against the grommet located in a receptacle in the receiving end of the tool. The pressure exerted by the lever prevents the grommet from inadvertently being mispositioned prior to and during the operation of the tool. Furthermore, when sufficient tension is put on the endless loop and consequent pressure is applied to the body part to be severed, the lever is used to deform the grommet upon and/or around the endless loop to secure the loop around the animal's body part. When it is desired to release the tool from the ligature material, the lever position is reversed.

In another aspect of the present invention, the ligation method and apparatus of the present invention may be used with a novel method for raising cattle, and more particularly bulls, wherein there is an increase in the quantity and/or quality of meat produced, as well as a reduction in the practice of administering hormonal supplements to steers. That is, this aspect of the present invention combines the use of ligation as disclosed herein within the context of a novel cattle raising management program. In particular, the modifications provided by the present invention include steps for reducing cattle stress and sickness during: weaning, placing calves in unfamiliar surroundings, providing calves with unfamiliar feed, and castration.

More particularly, the novel cattle management program commences weaning at approximately 50 to 200 days, and more preferably at approximately 100 to 150 days from birth. Young cattle are kept with their mothers in the pasture and are “creep fed” in the pasture by providing liquid feed in a container designed to preclude access by older animals while allowing younger calves to freely feed on such liquid feed supplement. Young cattle are then moved from the pasture to a feedlot for weaning purposes. Prior to or at about the time of weaning, vaccines and a specially formulated liquid feed supplement are administered to the calves for preventing, for example, stress induced sickness due to early weaning. The calves are weaned at approximately 100 to 200 days from birth and provided the same liquid feed supplement used in the pasture feeding, together with conventional feed sprayed with such liquid feed supplement. In one embodiment of the invention, the young cattle are moved to a feedlot which has a feeding container therein having the identical liquid feed supplement fed to such cattle prior to weaning. The feedlot is also supplied with a feed container that has conventional feed therein, such feed coated and/or mixed with the same liquid feed supplement. In this way, young cattle are moved to a place (e.g., the feedlot) where there are present familiar aspects to the young animals, including the feed container used prior to weaning and the availability of the now familiar liquid feed supplement. The smell and taste of the liquid feed supplement on the more conventional feed encourages the animals to start eating more conventional feed sooner and thus, such animals gain weight more rapidly and are healthier during the weeks after their conveyance to the feedlot. This greatly reduces the stress on such animals and, importantly, maintains the eating habits of the animals during such transition.

When the bulls are between approximately seven months and ten months of age, they are castrated using the ligation method and apparatus of the present invention, which is substantially less stressful and more effective than other castration methods. Castration at such time achieves the increased muscle and frame development possible with an intact bull while avoiding the unfavorable characteristics of a mature bull. Also, concurrent with such castration, infection preventative measures are administered, such as a tetanus injection. The present invention provides for a more humane method by which to castrate animals. The bloodless castration device provided by the present invention is a vast improvement over the traditional method of castration involving severing an animal's testicles with a knife during the branding of young calves. The present method is also safer than conventional methods of castration since it does not involve sharp knives typically used in conventional castration procedures where the inevitable movement of an animal during the procedure creates an opportunity for the human operator to suffer cuts to his/her own body.

It is a common experience using conventional practices for young calves, after being removed to a feedlot, to cry out for their mothers and to constantly walk around the feedlot in a semi-panicked and stressed state. During this stressful time period, calves often experience no gain in weight due to their unfamiliarity with the surroundings and their reluctance to eat conventional feed. The stressful conditions and the reduction in the amount of food consumed by such animals, often results in such animals getting sick. Using the present invention, however, it has been found that young calves gain substantially more weight for the first three weeks in the feedlot.

Thus, it is an important aspect of this cattle management program that cattle, and in particular bulls, increase in size and muscle substantially faster than cattle do using conventional cattle raising practices. In particular, by castrating in the age range mentioned hereinabove (rather than the conventional practice of castration at branding time (e.g., birth to approximately two months)), the natural growth hormones secreted by the testicles (namely, testosterone) cause the male animals to grow larger, more rapidly and without the need for (and related expense of) artificial hormones. Further, by castrating during the above-mentioned age range, substantial growth can take place without undesired masculization. Accordingly, the meat derived from such steers has a higher lean-to-fat ratio, with improved cutability characteristics. Tenderness and palatability improvements of meat derived from such animals is also achieved, such factors largely relating to the age of the animal. Accordingly, due to the accelerated growth of cattle raised using this novel cattle management program, cattle may be slaughtered at one year to fourteen months from the date of birth, rather than the more conventional time periods of at least eighteen months to two years from birth. Accordingly, using the present invention, there is a substantial savings in the cattle raising overhead due to the shortened time frame involved. For example, maintenance costs involved in keeping an animal alive for additional months are eliminated, allowing ranchers to not only improve their profit margins, but also to more quickly pay back loans typically required in ranching operations.

Additionally, in a preferred embodiment of the novel cattle management program of the present invention, the liquid feed supplement provided to the cattle has approximately the following ingredients: corn condensed distillers solubles (a by-product of alcohol production); corn steep liquor (a by-product of starch production); vegetable fat (a by-product of corn oil refining) and Protoferm (a by-product of monosodium glutamate). Preferably, the liquid feed supplement comprises approximately 16% protein, of which approximately 56% is natural, with the remaining being non-protein nitrogen in the form of ammonium chloride. The mixture also preferably has approximately 10% fat content and 45% solids. A preferred feed formulation is MIX 30™, available from Timberlake Sales, P.O. Box 7510, Springfield, Ill.

The present inventor is believed to be the first to recognize the advantages of using substantially the same liquid feed enjoyed by calves in the pasture as a feed supplement mixed with more conventional feed mixtures to familiarize cattle with conventional feed. In combination with the novel castration method developed by the present inventor, it is now possible to raise cattle in a manner that significantly increases their growth, reduces stress and provides for healthier weight-gaining animals in a far shorter time period when compared with conventional cattle raising practices. The result is an improved quantity of quality meat yield from such animals and an overall reduction in the costs involved in the cattle raising process.

Other features and benefits of the present invention will become apparent from the detailed description with the accompanying figures contained herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1

is a top view of an apparatus constructed in accordance with the present invention.

FIG. 2

is a side view, partially cut away, of the apparatus of FIG.

1

.

FIG. 3

is a side elevational view of the apparatus of

FIG. 1

with the crimping arm in a deflected position.

FIG. 4

is a front elevational view of the apparatus of FIG.

1

.

FIG. 5

is a front elevational view of the apparatus of

FIG. 1

with the crimping arm in a deflected position.

FIG. 6

is a side view, partially cut away, of an apparatus constructed in accordance with the present invention showing a cutting assembly.

FIG. 7

is a front view of the apparatus of FIG.

6

.

FIG. 8

is a side partial section elevational view of one embodiment of the present invention in which a power winding source is integral with the ligation tool itself.

FIG. 9

is a top partial section view of one embodiment of the present invention in which a power winding source is integral with the ligation tool itself.

FIG. 10

is a top view of the present invention depicting a winding tether attached to a winding spool and a crimping bar pivotally mounted in the receiving end of the tool.

FIG. 11

is a perspective view of the present invention showing the biasing pin, lever, crimping bar and substantially square receptacle located in the receiving end of the tool.

FIG. 12

is a perspective view of the tool showing an integral prong attached to the winding spool.

FIG. 13

is a plan view of the endless elastomeric loop and attached grommet.

FIG. 14

shows a plan view of an alternative embodiment of the endless elastomeric loop and attached grommet.

FIG. 15

shows yet another embodiment of the endless elastomeric loop and attached grommet.

FIG. 16

is a plan view or top view of a ligating tool constructed in accordance with the present invention, wherein this embodiment includes a tension indicator for displaying to an operator of the tool the amount of tension being provided on an elastomeric loop for ligation.

FIG. 17

is a side view of a portion of a ligation tool for the present invention, wherein the grommet crimping lever

62

has a smooth cammed upper surface

390

for use in crimping a grommet

32

.

FIG. 18

illustrates another embodiment of a mechanism for crimping a grommet

32

, wherein the lever

62

does not directly contact the crimping bar

114

as in FIG.

17

. Instead, a link piece

394

connects the lever

62

and crimping bar

114

for crimping a grommet

32

.

FIG. 19

is an end view of the second end portion

26

shown in FIG.

18

.

FIG. 20

shows a cutting tool useful with some embodiments of the ligation tool of the present invention, wherein the cutting tool cuts the endless elastomeric loop once its surrounding grommet

32

has been crimped.

FIG. 21

shows an alternative embodiment of the crimping bar

114

, wherein this embodiment is useful in an embodiment of the ligation tool that cuts the elastomeric loop after its associated grommet

32

has been crimped by continued pivoting of the lever

62

.

FIG. 22

is a perspective view of the crimping bar embodiment of FIG.

21

and the additional components used for providing a passageway in which an elastomeric loop is cut once its associated grommet

32

is crimped.

FIG. 23

is a side view of a portion of an embodiment of a ligation tool for the present invention, wherein this portion illustrates the interaction between the crimping bar

114

embodiment of

FIG. 21

with the lever

62

for cutting the elastomeric loop after its associated grommet

32

has been crimped.

FIG. 24

is another embodiment of an endless elastomeric loop and attached grommet for the present invention.

FIG. 25

shows a flow chart of the steps of the cattle raising management program aspect of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

I. Ligation Method and Apparatus

Referring to

FIGS. 1-4

, an apparatus constructed in accordance with an embodiment of the present invention is generally identified by the reference numeral

10

. As shown, the apparatus

10

comprises a tool body

12

, a winding assembly

14

and a crimping assembly

16

.

The body

12

receives a band

18

of ligature material, wherein a loop

20

of ligature material is formed external to the apparatus

10

about an animal body part to be removed. The loop

20

is then progressively tightened by winding the band

18

about winding assembly

14

to substantially cut off blood flow and systemic support to the animal body part. Preferably, the ligature material comprises an elastomeric material such as surgical tubing. However, because of the large tightening forces which can be achieved with the apparatus

10

, relatively inelastic band materials such as rope and/or wire may be successfully employed.

The tool body

12

, which may comprise steel or other material having sufficient strength to withstand the forces encountered during ligation procedures, has a handle

22

at a first end portion

24

thereof and a second end portion

26

which is adapted to receive the band

18

of ligature material. The handle

22

may be contoured for optimal handling by the user. In the illustrated embodiment, the second end portion

26

includes a passageway

28

sufficient to allow passage of the band

18

therethrough. The second end portion

26

can also include a receptacle

30

adapted to hold a grommet

32

which can be crimped, as will be described below, to secure the band

18

after the loop

20

has been tightened. It will be appreciated that the band

18

of ligature material is pulled rearwardly through the passageway

28

towards the winding assembly

14

as the loop

20

is tightened. As illustrated, the second end portion

26

may be angled relative to a longitudinal portion

34

of the body

12

, the angle preferably selected such that a longitudinal direction of the second end portion

26

is directed towards the winding assembly

14

, thereby reducing frictional and binding contact between the band

18

and the second end portion

26

as the band

18

is pulled therethrough. Reducing such frictional and binding contact facilitates winding of the band

18

by reducing the effort which must be exerted by the user in winding and reducing the likelihood that the band

18

will become snagged and possibly break.

The winding assembly

14

is attached to the body

12

by way of frame

36

which may comprise steel or other material of suitable strength. Frame

36

provides a distance x between the body

12

and the winding assembly

14

which is sufficient to substantially prevent mechanical interference between the band

18

and the body

12

as the band

18

is wound about the assembly

14

. Preferably, the distance x is between about ¼ inch and two inches depending, for example, on the thickness of the band

18

employed. In the illustrated embodiment, the distance x is about ½ inch which has been found to provide sufficient clearance for a broad range of materials, including standard surgical tubings.

In one embodiment of the present invention, the winding assembly

14

comprises a spool

38

which is rotatably mounted on the frame

36

and a winding engagement site

41

operatively connected to the spool

38

is provided which can be rotated by a pneumatic, electrical, or more preferably hydraulic power motor

43

, such motor being integral to or alternatively separate from the frame

36

. The power tool

45

or motor

43

utilized must be capable of engaging the winding engagement site

41

in a manner so that the winding means

14

is turned or rotated, thus facilitating the accumulation of ligature material on the winding assembly

14

. In one embodiment, the winding engagement site

41

comprises a suitably designed protuberance, such as a nut having several sides, or an indentation, similarly having a plurality of sides, engageable by a suitably complementary power tool

45

device that is capable of activating the winding means

14

to achieve rotation thereof. The compatible multi-sided protuberance or multi-sided indentation is configured so that engagement of the power tool

45

or motor device

43

with such protuberance or indentation will facilitate the powered rotation of the winding means

14

.

In another embodiment, the powered winding of ligature material is achieved by the incorporation of a pneumatic or electrical device into the tool's

10

overall design so that a separate power tool

45

need not be interconnected or engaged with a separate powered tool. As such, the incorporation of a pneumatic or electrical powered motor

43

that is integral with the castration tool

10

is within the scope of the present invention. An illustrative embodiment of such embodiment is shown in

FIGS. 8 and 9

.

With reference to

FIGS. 8 and 9

, a pneumatic device

21

is incorporated into the handle

22

of the tool

10

. An air supply

23

can be interconnected with one end of the handle

22

to operate an air piston

25

residing within the handle

22

. An air control valve

27

located on the handle

22

can be used to control the winding operation so as to achieve desired winding of ligature material about the spool

38

. In one embodiment, a drive linkage

29

between the pneumatic device

21

and the winding assembly

14

is provided to permit operation of a ratcheted lever

31

having an axis of rotation coincident with the axis of rotation of the spool

38

. The lever

31

is attached to a ratchet mechanism

52

so that the spool

38

can be selectively rotated in alternative directions. The drive linkage

29

is operatively attached to a piston rod

33

which is driven by the air piston

25

located in the tool's handle

22

. Upon operation of the air piston

25

, the piston rod

33

is moved back and forth within the body

12

of the device. Through such movement the drive linkage

29

communicates with the ratcheted lever

31

to rotate the spool

38

in a desired direction. Winding of the ligature material

20

around the spool

38

can thus be accomplished by regulating the number of times the air piston

25

is forced forward and backwards, thereby ratcheting the ligature material

20

around the spool

38

to achieve a desired tension of the ligature loop

20

. In another embodiment, an electric or pneumatic motor is incorporated into the handle

22

of the tool

10

and is interconnected to a worm gear or other type of gearing mechanism. The worm gear is then operatively positioned to another gear interconnected to the winding spool

38

. As can be appreciated by one skilled in the art, numerous types of gearing configurations may be implemented to transfer power from the motor to the winding spool

38

.

In some applications, it is important to regulate the tightness or tension of a ligature loop

20

to prevent breakage thereof or to prevent injury to the animal. The tightness of ligature material can be regulated by adjusting the amount of force communicated by the rotation of the winding means

14

by a motor

43

. This can be accomplished by, for example, a clutch mechanism

47

either incorporated into the winding means

14

or, alternatively, can be a feature of the power tool

45

. For instance, a pneumatic power tool

45

capable of rotating the winding means

14

can be adjusted so that no further rotations occur after a predetermined tension or torque is achieved, at which point air is bled from the pneumatic power tool

45

rather than being used to rotate the winding assembly

14

. The ligature material is therefore wound about the winding means

14

to a predetermined tension, such tension regulated by a clutch mechanism

47

operatively associated with the motor

43

or in alternative embodiments, a feature of the power tool

45

.

As can be readily appreciated, the rate at which the loop

20

is tightened will depend upon the diameter of the spool

38

and the speed of rotation of the spool

38

. In addition, the tension which can be imparted to the band

18

by winding the band a predetermined number of times around the spool

38

or, alternatively, by gauging the tension or torque exerted on the winding assembly

14

so that at a predetermined desired tension, the spool

38

is no longer rotated. The diameter of the spool

38

can therefore be selected to allow the desired rate and degree of tightening. Although it is believed that a broad range of spool

38

diameters would provide adequate results, the illustrated spool

38

has a diameter between about ½ inch and ¾ inch. Such a diameter allows for rapid tightening of the loop

20

and allows the loop

20

to be sufficiently tightened to substantially cut off blood flow and systemic support to the body part to be removed.

The spool

38

further includes fasteners

44

to attach the band

18

to the spool

38

. The fasteners

44

may comprise a slotted portion of the spool

38

, a clip biased against the spool

38

or any other device by which the band

18

can be secured to the spool

38

. Where an elastomeric band is employed, is it expedient to provide a fixed element closely adjacent to a surface of the spool

38

so that the band

18

can be frictionally secured therebetween. In the illustrated embodiment, the fasteners

44

comprise cantilevered rods extending inwardly from flanged end portions

46

of the spool

38

. The fasteners

44

can be positioned such that the space between the spool

38

and a fastener

44

is progressively restricted from a free end

48

to a base

50

of the fastener

44

. Such a configuration allows the band

18

to be quickly and reversibly secured to the spool

38

by inserting the band

18

between the spool

38

and the free end

48

and then sliding the band

18

towards the base

50

until the band

18

is securely wedged therein.

The winding engagement site

41

is interconnected to the spool

38

such that the spool

38

can be rotated by turning of the winding means

14

. A ratchet assembly

52

can be employed to facilitate rapid tightening of the loop

20

. The assembly

52

comprises a first ratchet and pawl mechanism

54

which cooperates with a second ratchet and pawl mechanism

56

at the opposite end of the spool

38

to allow rotation of the spool

38

in only one direction. The user can thus tighten the loop

20

through repeated turnings of the spool

38

and the pneumatic or electric winding device

43

can be adjusted so that at a desired tension, no further winding of the spool

38

occurs. The present invention therefore provides a method and device that facilitates the speedy ligation of animal parts, and thus considerably shortens the time period required to perform the ligation procedure. This spares the user from exposing himself/herself to extended periods of danger encountered when working with large animals and lessens the discomfort of the animals.

Although particular dimensions for the illustrated embodiment have been provided, it is within the scope of the present invention to have a tool body of any dimensions, thus allowing for variation of the distance between the operator and animal.

Although not shown, it will be appreciated that the ratchet assembly

52

could be eliminated and the winding engagement site

41

could instead be rigidly interconnected to the spool

38

with appropriate modification of the apparatus

10

. It will be further appreciated that a winding engagement site

41

can be positioned on either or both sides of the body

12

to facilitate right hand or left hand users.

After the loop

20

has been tightened, the loop size can be maintained by securely interconnecting portions of the band

18

adjacent the loop

20

. The portions may be interconnected by using an adhesive; stapling, pinning or heat sealing the band

18

; binding portions of the band with wire, rope or the like; or any other suitable method for securing the loop

20

. In the illustrated embodiment, a crimping assembly

16

is provided to crimp a grommet

32

after the loop

20

has been tightened, thereby securing the loop

20

. The grommet

32

preferably comprises a cylindrical structure having an interior passageway sufficient to allow passage of the band

18

therethrough and can be formed from aluminum or other deformable material. During the ligation procedure, the grommet

32

is housed within a receptacle

30

of the second end portion

26

. As shown most clearly in

FIG. 4

, the receptacle

30

can include an internal annular shoulder

60

such that the grommet

32

can be positioned by sliding the grommet

32

into the receptacle

30

until an end of the grommet

32

abuts the shoulder

60

.

The grommet

32

used with the present invention can be of any desired shape and dimension to fit appropriately in the receptacle

30

. The grommet

32

must be capable of being properly crimped in a manner sufficient to hold two bands

82

together so as to form a loop

20

of ligature material. The grommet

32

must retain the loop

20

in a tensive condition during the atrophy process which may take several weeks. Further, the grommet

32

is designed so as to securely fasten the ligature material without significantly damaging the material. The grommet

32

can be a completely enclosing angular structure or may alternatively be configured with side portions bendable to secure each individual end of the ligature material, thus independently fastening each end without being dependent upon the adjacency of the other end to achieve a secure loop

20

. The grommet

32

may further include indexing means comprising indentations or protuberances so that the grommet

32

is properly oriented within the tool

10

to achieve a desired crimping configuration.

The crimping assembly

16

comprises a lever

62

which is pivotally mounted on the body

12

by way of a fulcrum

64

such as a pin. The user can move the lever

62

from a retracted position (

FIG. 3

) to an extended position (

FIGS. 4 and 5

) by urging the rearward end

66

of the lever

62

downwardly as viewed in the figures. In the extended position, the forward end

68

of the lever

62

extends into the receptacle

30

to deform the grommet

32

. As shown, the fulcrum

64

is preferably positioned towards the forward end

68

of the lever

62

so that a relatively small downward force exerted on the rearward end

66

of the lever

62

by the user results in a greater crimping force on the grommet

32

.

The fulcrum

64

penetrates a bulge portion

70

of the lever

62

which extends through a slot

72

in the body

12

. Forwardly from the fulcrum

64

, the lever

62

tapers so that the lever

62

can be fully withdrawn from the receptacle

30

in the retracted position. In addition, the illustrated lever

62

includes a downwardly extending portion

74

adjacent the rearward end

66

of the lever

62

to avoid mechanical interference with a flange

76

of the handle

22

and to provide sufficient clearance between the body

12

and the lever

62

for gripping by the user. If desired, the lever

62

may be contoured for optimal handling by the user or a grip (not shown) may be interconnected with the lever

62

for this purpose.

Referring to

FIGS. 6 and 7

, side and front views, respectively, of an apparatus

78

constructed in accordance with the present invention are shown. The apparatus

78

includes a cutting assembly

80

for cutting the band

82

rearwardly of the grommet

84

after the loop

20

has been tightened. Any device for cutting the band

82

may be employed in accordance with the present invention. For example, a hand-held razor, scissors or other cutting tool

10

may be employed. In the illustrated embodiment, the assembly

80

comprises a razor

88

slidably mounted within a housing

90

which is interconnected to or integral with the apparatus body or frame. Preferably, the cutting assembly

80

severs the band

82

a suitable distance rearwardly of the grommet

84

to reduce the likelihood that the band

82

will be pulled through the grommet

84

after severing. In this regard, it will be appreciated that elastomeric bands tend to constrict under tension and expand after severing such that such bands may slide a distance through the grommet

84

before becoming secured therein.

The razor is slidable from a retracted position, wherein the cutting surface of the razor

88

is protectively housed within housing

90

, to an extended position (as shown in phantom in

FIG. 7

) wherein the cutting surface of the razor

88

extends into the band passageway to cut the band

82

. The razor

88

can be moved from the retracted position to the extended position by pressing downwardly on an upper surface

92

of the razor

88

, such that the upper surface

92

is urged downwardly through finger cut-out

94

. Preferably, the razor

88

is biased upwardly, e.g. by a spring, so that the razor

88

remains in the retracted position until the razor

88

is pressed downwardly. Alternatively, a cutting mechanism

88

can be pivotally connected to the tool body

10

so that the band

82

is severed from below by simply pivoting of the cutting mechanism to bring the razor

88

into contact with the band

82

. It will be appreciated that such a pivoting cutting mechanism can be used in embodiments where continuous or long lengths of banding is utilized and is not confined to use with continuous loops.

In operation, a tool

10

may be employed in accordance with the present invention to ligate a body part as follows. Initially, a band of ligature material is either looped around the body part and inserted through an end portion of the tool

10

and a grommet

32

housed therein, or a loop

20

is preformed and then positioned around the body part to be ligated. End portions of the band can then be attached to a spool by sliding the end portions between fasteners and the spool such that the end portions are frictionally engaged therebetween. Although not shown in the illustrated embodiments above, it will be appreciated that it would be sufficient to attach only one end portion of the band to the spool. For example, one end portion of the band could be connected to the spool and a second end portion could be connected to the body. In this regard, attaching the band to the spool at two end portions has the advantage that the band can be tightened quickly and evenly. However, attaching the band to the spool at only one end portion and allowing the other end portion to remain stationary as the band is tightened has the advantage that the stationary end portion need not be severed from a supply of band material prior to winding the band.

After the band is secured to the spool, the band can be tightened by turning or rotating the winding means

14

. The band can be tightened by operation of a pneumatic or electrical winding tool

10

that engages the winding assembly

14

to thereby cause the spool to rotate, tightening the ligature loop

20

. The present invention therefore provides a method and device for tightening a loop

20

around a body part without expenditure of physical strength, such as a user's hand strength. The tightness of the loop

20

is therefore not limited by the user's hand strength, allowing for the expedited ligation of body parts.

When the loop

20

is tightened sufficiently, the loop

20

can be secured by moving a crimping lever to an extended position thereby deforming the grommet

32

so that the band portions therein are frictionally secured. Thereafter, the band may be severed with a cutting tool

10

, e.g., a razor, rearwardly of the grommet

32

leaving the loop

20

attached to the body part.

Another aspect of the present invention involves an endless elastomeric ligature loop

100

used for ligation of body parts, and particularly for castration. The prior art discloses the manual formation of an endless loop around a body part of an animal utilizing two ends from a substantially linear band of ligature material. The ends of the ligature bands are then attached to a means for pulling one or both of the ends of the ligation material to tighten the manually formed loop around the body part. In contrast, the present invention provides a preformed endless loop that is easy to attach to a tool for winding or pulling, and subsequently decreases material costs due to the absence of any excess length of ligature material used in securing such material to the ligation tool. The use of preformed endless loops of material, particularly loops having a pre-attached grommet thereon, reduces the time required to apply the endless ligature loop around the body part of a restrained animal. In a preferred embodiment, the endless loop is manufactured from an elastomeric material having a high tensile strength that is resistant to abrasion and tearing. More preferably, the elastomeric material is comprised of a non-hollow rubber material either molded or extruded to produce a finished elastomeric product without ends. As an alternative to using a manufactured preformed elastomeric loop without ends, an elastomeric endless loop may be formed by attaching or connecting the two ends of a straight length of an elastomeric band of rubber or surgical tubing with a clip, wire band, grommet, or other device which prevents the two ends from being separated. In a preferred embodiment, a heavy gauged wire may be used to secure the two ends of the elastomeric band and may further include an end piece capable of being attached to a means for winding or pulling (e.g., hook-like structure).

The endless elastomeric ligature loop

100

is positioned in the receiving end of the tool and connected to an attachment means located on the winding spool

38

(or any suitable pulling means). In a preferred embodiment, a hook-like structure or prong is used to contact the loop and allow the loop to be pulled or wound as shown in FIG.

12

. The prong

102

attached to the winding spool

38

may have an integral hook or other type of attachment mechanism to prevent loss of contact with the endless loop during a winding or pulling operation. In a preferred embodiment shown in

FIGS. 10 and 12

, a hook

104

, which attaches to the endless loop is connected to a winding tether

106

, which is in turn connected to the winding spool

38

. As the winding spool

38

is rotated, the winding tether wraps around the winding spool and begins pulling the endless loop

100

towards the winding spool

38

once sufficient slack is removed from the winding tether

106

. The winding tether

106

may be comprised of rope, leather, steel cable, or any other suitable material with a tensile strength sufficient to withstand the forces necessary to operatively tighten the elastomeric loop around the scrotum or other body part of an animal. The endless loop

100

can thus be attached to the winding mechanism quickly without being torn or damaged when tension is placed on the endless loop

100

. Furthermore, by utilizing an endless loop in combination with a winding tether

106

, significant savings in material costs are realized since the overall length of the endless loop can be decreased. The winding tether

106

and integral hook assembly may be seen in FIG.

10

.

Once the endless loop

100

is pulled and/or wound to a desired tension, the loop is constricted so that it is secured around the body part to be ligated. Any suitable means of securing two opposing portions of a loop can be used, including mechanically affixing the loop together or thermally melting the loop material to form a bonding point. Preferably, a grommet

32

is used to secure the endless loop material in a fixed position once sufficient tension is placed on the endless loop to apply adequate pressure around the body part of an animal. The grommet

32

is comprised of metal or any other material which can be permanently deformed. The material preferably has a surface smooth enough to prevent any abrasion when in contact with the elastomeric ligature material, thus preventing tearing of the ligature material. More preferably, the grommet is comprised of rolled flat wire with a length and width sufficient to prevent the ligature material from slipping through the grommet

32

after the grommet

32

is deformed upon the endless loop

100

.

In one embodiment, a grommet

32

is attached to the endless loop

100

prior to actual use, thus assuring that the grommet

32

is attached in a proper manner not likely to damage the endless loop and also preventing the possibility of tightening the loop without first having a grommet in place. Furthermore, by preattaching the grommet

32

to the endless loop, time is saved in the ligation process since the step of feeding the ligature material through the grommet

32

is eliminated. Preferably, and as depicted in

FIG. 13

, the grommet

32

is attached to the endless loop

100

between a forward end and rearward end of the endless loop, thus forming a forward loop

108

and rearward loop

110

, similar to a modified figure-eight or hour-glass configuration. The forward loop

108

extends forward of the receiving end of the tool and the rearward loop

110

extends rearward of the receiving end of the tool. More preferably, the forward loop

108

should be of sufficient circumference to allow it to be easily placed around a selected body part of an animal, such as a scrotum. The rearward loop

110

preferably has a circumference large enough to either allow the attachment of a hook attached to a winding tether

106

(or other pulling means), or to be placed over a prong

102

extending from the winding spool

38

. The pre-attached grommet

32

must be loosely attached to the band in a manner that allows the ligature material to slip through the grommet

32

until desired tension on the body part is achieved. At such time, the grommet

32

is deformed to permanently secure the tightened band around the body part.

The receiving end of the tool may have a variety of geometric configurations suitable to receive an equally numerous number of grommet

32

designs. Preferably, the receiving end of the tool has a receptacle

30

with substantially rigid opposing side walls. More preferably, the opposing side walls and opposing top and bottom walls are parallel to one another, whereby the receptacle is substantially square or rectangular in shape. Other embodiments (not shown) can have a receiving end that is open on a top, bottom or side to facilitate easier loading of grommets into the tool.

As shown in

FIG. 11

, the lever

62

pivotally mounted on the body of the tool may be held in a biased position with a biasing pin

112

against the grommet

32

when the grommet is in the receiving end of the tool. The biasing pin

112

may be metallic or any other durable material and extends downward from the tool body. By utilizing a spring, coil or other biasing means, the biasing pin

112

applies constant downward pressure on the lever arm

62

, which transfers pressure against the grommet

32

located in the receptacle

30

of the tool. The constant pressure applied by the biasing pin

112

prevents the grommet

32

from inadvertently falling out of or from becoming mispositioned in the receptacle

30

of the tool. Once the endless loop

100

is tightened sufficiently around the body part of the animal, the lever

62

is used to permanently deform the grommet

32

upon the endless loop

100

, thus preventing the endless loop

100

from slipping through the grommet. After the grommet

32

is deformed, the lever position is reversed by applying pressure on the rearward portion of the lever in a direction towards the tool body, thus disengaging the tool from the grommet, and thus from the formed endless loop

100

. Other means for retaining the grommet in the tool (not shown) include the use of a magnet to reversibly hold a ferrous grommet in place and the use of reversibly flexible structures on the tool and/or the grommet, that act to secure the grommet in a loose fashion to the tool.

As illustrated in

FIG. 10

, the crimping assembly may additionally include a crimping bar

114

located within the receiving end of the tool. Preferably, the crimping bar

114

is pivotally positioned within the receiving end

116

of the tool. The crimping bar

114

is positioned to transfer force from the lever

62

to the grommet

32

when the grommet is positioned in the receptacle

30

in the receiving end

116

of the tool. The crimping bar

114

may be made of steel or other suitable material hard enough to deform the grommet. More preferably, the rearward end of the crimping bar

114

located closest to the winding mechanism of the tool is riveted to the tool body, while the opposite end of the crimping bar

114

is positioned against the grommet

32

. As the lever handle is pushed downward and away from the tool body, the upper surface of the lever

62

transfers force to the crimping bar

114

, which rotates or pivots upward around the rivet, deforming the grommet. Although the crimping bar

114

used in the present invention has a circular cross-sectional shape, any geometric configuration capable of deforming the grommet may be utilized effectively.

One aspect of the present invention therefore relates to a ligation tool having a pivotally mounted lever

62

that is operated after ligation material is tightened sufficiently around a body part to be ligated, the operation of such lever effective to crimp a grommet

32

to secure the ligation material together. Prior art devices have utilized a crimping structure involving elongate crimping rods that when rotated, pivot crimping dogs against a grommet to crimp the grommet about tensed ligature material. (See Wadsworth, U.S. Pat. No. 4,691,704). The use of the pivotally mounted lever mechanism to crimp a grommet as disclosed herein provides for a far easier method of operation than crimping operations involving prior art devices. (See

FIGS. 2

,

3

,

6

and

11

).

The deformation of the grommet against the endless loop

100

thus maintains the endless ligature loop in substantially constant tension around a scrotum or other body part of the animal. Although a grommet is preferably used to secure the endless loop in a fixed position around a body part of an animal, other means for securing the endless loop will be obvious to those skilled in the art. These means include, but are not limited to, the use of plastic or metallic bands or straps, glues, and the application of heat to effectively melt the elastomeric ring in a substantially fixed position.

In a further embodiment of the present invention, means for pulling the endless elastomeric loop

100

rearward to apply tension to the elastomeric loop may be accomplished by rotating the elastomeric loop behind the receiving end of the tool in a direction substantially perpendicular to the longitudinal axis of the tool. This twisting of the loop material around itself (similar to the twisting of a rubber band on a toy propeller airplane) effectively tightens the loop around a body part and eliminates the need for any pulling mechanism. Preferably, the endless elastomeric loop

100

is attached to a sleeve (not shown) which rotates within the tool body and includes an integral hook or pin which attaches to the endless loop. As the sleeve rotates, the endless loop located rearward of the receiving end

116

of the tool rotates, thus shortening the endless loop and applying tension on the portion of the endless loop located forward of the receiving end of the tool. Once sufficient tension is applied to the endless loop

100

, a grommet

32

may be attached to the endless loop

100

and deformed at a point adjacent the body part to be ligated.

Another aspect of the present invention involves a method for ligating a body part of an animal, preferably a scrotum. The method involves manually passing a preformed endless loop of ligature material around the body part of the animal. The endless loop is then pulled using various means integral to the ligature tool (e.g. winding mechanisms, pulling mechanisms, etc.) to tighten the loop around the animal's body part. Once the endless loop is sufficiently tightened, the endless loop is secured to maintain adequate pressure around the animal's scrotum. Preferably, the step of securing comprises deforming a grommet around the endless loop, while the pulling of the endless loop is accomplished by winding the endless loop around a winding spool integrally attached to the ligature tool. To improve the efficiency and cost of the method, a winding tether and attached hook may be utilized to reduce the overall length of ligature material necessary. After the grommet is deformed around the endless loop, the excess ligature material not applied around the animal's body part may be removed by cutting the endless loop that is not around the body part with a sharp knife, razor blade or other suitable instrument. Alternatively, the band material can be unwound or otherwise released from the tool, thus eliminating the need to cut the band so as to release it from the tool.

The present invention has a number of advantages over other ligation methods and tools. First, the present invention allows a band to be tightened quickly and easily, thereby reducing the time that the animal must be restrained. In addition, the present invention allows the band to be set tightly such that blood flow and systemic support to the body part can be reliably cut off, thereby reducing the likelihood of swelling, infection, prolonged stress to the animal and/or failure of the ligation procedure. Further, because the band is progressively wound about the spool as the loop

20

is tightened, tension forces are spread relatively evenly over the band during the ligation procedure, thereby reducing the likelihood that the band will fail. It is a further advantage of the present invention that larger and stronger elastomeric materials, or relatively inelastic materials, may be used. The present invention also has ease-of-use advantages as band tightening and crimping can be accomplished with relatively little effort. Additionally, the use of a preformed endless elastomeric loop saves time by eliminating the step of attaching loose ends of an elastomeric band to a means for pulling during the ligation operation. Ligature band material costs are also reduced by utilizing a winding tether which is attached to a pulling means, such as the winding spool of the present invention. Further, by preattaching a grommet to the endless loop, proper positioning of the grommet around the endless loop is assured. The possibility of the grommet being jarred from proper positioning in the receiving end of the tool is also minimized by means for holding the grommet in place, for example, by use of the biasing of the lever and crimping bar as previously discussed.

FIGS. 16-19

and

21

-

23

include further embodiments of the castration apparatus

10

of the present invention. Note that

FIG. 16

provides a top view of the castration apparatus

10

that illustrates many of the aspects of the embodiments in FIGS.

16

-

19

and

21

-

23

. Accordingly, for illustration purposes, a portion of the body

12

is cut away in

FIG. 16

to illustrate internal components. Further, the embodiments of these figures are different from previous embodiments in one or more of the following ways:

(a) there is a castration loop tensioning indicator (

352

) provided on the apparatus

10

(

FIG. 16

) for assisting in determining when an effective castration tensioning has been applied to a castration loop such as various embodiments of the loop

100

provided hereinabove (e.g., tension of up to about 80 to about 120 lbs, more preferably about 100 lbs);

(b) there are alternative configurations for crimping a grommet

32

(

FIGS. 17-19

) once an effective castration tension has been placed on a loop

100

. In particular, these embodiments are similar to the embodiment of

FIG. 11

in that the grommet

32

has its opposing perimeter sides squeezed together between the crimping bar

114

and the receptacle

30

in a manner so that the opposed sides of the perimeter remains substantially parallel thus providing a more secure castration loop locking ability;

(c) there is an alternative configuration for the grommet crimping bar

114

and related components (

FIGS. 21-23

) so that the action of the lever

62

both crimps a grommet

32

and automatically cuts the excess elastomeric material from the loop after the grommet has been crimped.

Referring now to

FIG. 16

, this figure illustrates one embodiment of the castration apparatus

10

, wherein a tensioning indicator

364

is illustrated. For brevity, components of this embodiment having similar functionality and structure to previous embodiments are labeled identically. Accordingly, only the new or modified features related to the tension indicating capabilities of this embodiment are herein described. Thus, note that the body

12

has been truncated so that it no longer extends to the receptacle

30

. Instead, the body

12

(also denoted a body member) truncates approximately at the forward end of the frame

36

. For providing the second end portion

26

of the present embodiment, a body member insert (or simply, body member)

304

is provided, wherein the end

308

of the body insert

304

(that is opposite the second end portion

26

) is positioned within a longitudinally extending bore

312

of the body member

12

, wherein this bore extends from an open end

316

to at least the handle

22

. Interior to the bore

312

and extending rearwardly from the body insert

304

is a reduced diameter shaft

320

having a threaded free end

324

. Inserted onto the shaft

320

is a compression spring

328

and a spring aligning spacer

332