NZ533072A - Stock drafting device - Google Patents

Abstract

A device in the form of a station for separating animals into two or more groups, the station capable of being used in association with an animal corral or other livestock holding equipment including vehicles for transporting livestock. The station includes: an entrance through which animals can enter the station; two or more exits through which animals can exit the station and thereby be directed into separate groups; a first moveable obstruction means that can be operated to selectively open and close the entrance of the station so as to allow an animal to enter the station; a second moveable obstruction means that can be operated to selectively open and close the exits so as to allow an animal to exit the station from one of the exits; a first detecting means for detecting when an animal has entered the station by passing through the entrance; and a second detecting means for detecting when an animal has exited the station by passing through one of the exits.

Description

5330 72 5330 72 Intellectual Property Office of NZ 19 MAY 2004 RECEIVED PATENTS FORM NO. 5 Fee No. 4: $250.00 PATENTS ACT 1953 COMPLETE SPECIFICATION STOCK DRAFTING DEVICE l/WE Paul Shewen & Co Pty Ltd, an Australian company of 13 Weinberg Street, P.O. Box 17, Cohuna, VIC 3568, Australia hereby declare the invention, for which I/We pray that a patent may be granted to me/us, and the method by which it is to be performed to be particularly described in and by the following statement: 1 James & Wells Ref: 123624/0 RJ STOCK DRAFTING DEVICE FIELD OF THE INVENTION The present invention relates to a device for 5 separating a herd of animals into two or more herds.

BACKGROUND OF THE INVENTION The task of separating a herd of animals into two or more herds has traditionally being carried out in 10 paddocks or stockyards.

Stockyards used to carry out this task commonly include a straight passageway or raceway that is defined by a pair of parallel fences and a drafting assembly positioned in the raceway for separating animals into two 15 or more herds. The drafting assembly is typically in the form of an opening in one of the fences of the raceway that leads to a holding yard and a gate that is pivotally mounted to the other fence opposite to the opening.

In use, the gate can be either manually or by 20 other suitable means moved across the raceway so as to direct an animal moving along the raceway to pass through the opening and thus into a holding yard off the opening. In the situation in which the animal in the raceway is to be kept separate from the herd in the holding yard off the 25 opening raceway, the gate is pivoted to a position parallel to the fences which allows the animal to continue along the raceway into another holding yard.

A difficulty with this type of drafting assembly is that an animal can pass through the opening in the 30 fence without the gate being pivoted across the raceway. Another difficulty is that an animal can stray from the holding yard off the opening in the fence into the raceway and drafting assembly.

More recently, attempts have been made to address 35 these difficulties by a drafting gate that includes a pair of the gates that can be pivoted in parallel relationship using hydraulic cylinders.

C:\windows\TEMP\FP19767.doc 17/05/04 It is an object of the present invention to provide an alternative device for separating a group of animals into two or more groups.

SUMMARY OF THE INVENTION According to the present invention there is provided a device in the form of a station for separating animals into two or more groups, the station capable of being used in association with animal corral or other 10 live-stock holding equipment including vehicles for transporting live-stock, the station including: a) an entrance through which animals can enter the station; b) two or more exits through which the animals can 15 exit the station and thereby be directed into separate groups; c) a first moveable obstruction means that can be operated to selectively open and close the entrance of the station and thereby allow an animal to enter the station; d) a second moveable obstruction means that can be operated to selectively open and close the exits so as to allow an animal to exit the station from one of the exits; e) a first detecting means for detecting when an animal has entered the station by passing through the 2 5 entrance; and f) a second detecting means for detecting when an animal has exited the station by passing through one of the exits.

In use, when the first detecting means detects 30 that an animal has past through the entrance of the station, the first obstruction means can be closed to prevent the animal from exiting the station via the entrance, and in addition, prevent another animal from entering the station prior to the animal in the station 35 exiting the station. The second obstruction means can be operated to open and/or close the exits so that the animal in the station is directed to join a desired group, mien C:\windows\TEMP\FPl9767.doc 17/05/04 the second detecting means detects that the animal has past through the desired exit, the exit may then be closed and the first obstruction operated to re-opened and allow another animal to enter the station.

Advantages provided by the present invention include: i) when an animal is in the station, the animal can be prevented from backing out through the entrance of the station; and ii) when the animal has exited the station, the exits are closed to prevent an animal from entering the station via the exits.

Although it is possible that the first and second detecting means may be in any form, it is preferred that 15 the detecting means be in the form of photo-electric sensor that emits an electromagnetic beam transversely across the entrance or the exits.

The term electromagnetic beam in this specification embraces both visible and non-visible 20 electromagnetic radiation including infrared and ultraviolet light.

It is preferred that the photo-electric sensors be arranged so that the beam be transmitted between either: i) a sender unit and a receiver unit on opposite 25 sides of the entrance or exits; or ii) a sender and receiver located on the same side of the of the entrance or exits and a reflector on the opposite side thereof.

When the beam emitted by the sensors has been 30 broken by an animal walking through the beam and the beam is subsequently restored by the animal moving past the beam, the first and second detecting means sends a signal to a controller that operates the first and second moveable obstruction means.

It is preferred that two of the exits be oppositely disposed side exits that face each other and the second moveable obstruction means includes a pair of C:\windows\TEMP\FP19767.doc 17/05/04 first gates, wherein one of the first gates is located at each exit of the station and defines a passageway between the gates for an animal so that in use, when one of the first gates is pivoted outwardly to open one of the exits 5 the other gate can be pivoted inwardly in parallel relationship such that the passageway between the gates directs the animal through the opened exit.

It is preferred that the first gates be interconnected by a linkage member such that pivotal 10 movement of one of the first gates can cause pivotal movement of the other first gate via the linkage member.

Accordingly, it is preferred that one of the first gates be pivoted inwardly and outwardly by a pneumatic or hydraulic piston and cylinder arrangement. The other 15 first gate can thus be driven inwardly and outwardly by the interconnecting linkage member.

It is preferred that the linkage member have a base that extends between the first gate members and two legs that project downwardly from the base on opposite 20 sides of the passageway defined between the first gate members.

It is preferred that the second detecting means emits an electromagnetic beam across the passageway so as to detect when an animal has past through the exit. 25 It is preferred that the second detecting means be mounted to the legs of the linkage member at a height suitable for directed when an animal has past through the passageway.

It is preferred that the linkage member be 30 pivotally mounted to each of the first gates such that components of the second detecting members can continually face each other while the first gates are pivoted inwardly and outwardly.

It is preferred that the linkage member be located 35 toward an end of the first gates opposite to the end at which the gates are pivotally mounted.

C:\windows\TEMP\FP19767.doc 17/05/04 It is also preferred that the device include a pair of second gates, wherein one of the second gates is located on the outside of each of the first gates and is prevented from moving inwardly when the first gate moves 5 inwardly, thereby preventing an animal from entering the station via the exits when the first gate has been pivoted inwardly.

It is preferred that the device also have a further exit and the second moveable obstruction means 10 allows animals to exit from the station via the further exit when the two side exits are closed.

Although it is possible that the first moveable obstructions means may be in any form, it is preferred that the first moveable obstruction means include a pair 15 of third gates that are aligned with each other to extend across the entrance of the station.

It is preferred that each third gate be driven by a pneumatic or hydraulic piston and cylinder arrangement.

A person skilled in the art of the present 20 invention will appreciate that suitable control devices and actuators including electric solenoid valves can be used to operate the first and second obstruction means when the first and second detecting means detect that an animal has entered or exited the station. 25 According to the present invention there is also provided a device in the form of a station for separating animals into two or more groups, the station capable of being used in association with animal corral or other live-stock holding equipment including vehicles for 30 transporting live-stock, the station including: a) an entrance through which animals can enter the station; b) a first moveable obstruction means that can be operated to selectively open and close the entrance of the station and thereby allow an animal to enter the station; c) two exits disposed on opposite sides of the station through which the animals can exit; C:\windows\TEMP\FP19767.doc 17/05/04 d) a second moveable obstruction means that includes a pair of first gates, wherein one of the first gates is located at each exit of the station and defines a passageway between the gates for an animal so that in use, when one of the first gates is pivoted outwardly to open one of the exits the other gate can be pivoted inwardly in parallel relationship so as to direct the animal through the opened exit; and e) a pair of second gates, wherein one of the second 10 gates is located on the outside of each of the first gates and is prevented from moving inwardly such that an animal is prevented from entering the station via the exits when the first gates are pivoted inwardly.

The second gates are also capable of moving 15 outwardly in response to each first gate moving outwardly.

In use, the first gates can be pivoted in parallel relationship such that when one of the first gates is pivoted inwardly the other gate is pivoted outwardly to open an exit. In this situation, the second gate located 20 at the exit that has been opened will be pivoted outwardly with the first gate. In order to prevent animals from entering the station via the opposite exit, (ie. the exit at which the first gate been pivoted inwardly,) the second gate will maintain a closed position by not pivoting 25 inwardly (or outwardly) .

The present invention as described in the two paragraphs immediately above may also include any one of the features described in the preceding paragraphs including first and second detecting means for detecting 30 when an animal has past through the entrance and exits of the station.

BRIEF DESCRIPTION OF THE DRAWINGS A preferred embodiment of the preferred embodiment 35 will now be described with reference to the accompanying drawings, of which: C:\wlndows\TEMP\FP19767.doc 17/05/04 Figure 1 is a top view of a drafting gate assembly having an entrance and three exits, two of which are side exits and the third exit is a forward exit, the two side exits of the drafting gate are closed; Figure 2 is a top view of the drafting gate in which one of the side exits is opened; Figure 3 is a top view of the drafting gate shown in Figure 2 in which the opposite side exit is opened; Figure 4 is a rear view of the drafting gate show in 10 Figure 1; and Figure 5 is a rear view of the drafting gate in which the exit to the right hand side is in the process of being opened.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The drafting gate assembly according to the preferred embodiment comprises four vertical posts and three pairs of pivotally mounted gates that are supported in a working position above the ground by the posts. As 20 can be seen in Figures 1 and 2, the posts may be regarded as forming forward and rear pairs of posts identified by reference numerals 10 and 11 respectively.

The spacing between the posts of each pair of posts, for example posts 10a and 10b, defines the width of 25 the assembly and the spacing between each pair of posts 10 and 11 represents the length dimension of the assembly. The width dimension of the assembly is selected such that it may be fitted to pre-existing raceways with only minimal alteration.

The fence lines identified by the reference numeral 12 in Figures 1 and 2 represent fences that define a raceway in an exiting stockyard, corral or other stock handling equipment.

The assembly is designed to enable animals passing 35 through the raceway to be selectively diverted to exit the assembly through one of three exits. Specifically, the preferred embodiment comprises three exits, two of which C:\windows\TEMP\FP19767.doc 17/05/04 are side exits and the other is a forward exit. An animal can pass through the forward exit when the assembly is operated to have a configuration as shown in Figure 1 such that an animal exits the assembly in the direction of 5 arrow A shown in Figure 1.

The first pair of guiding gates, identified by reference numeral 13, comprises guide gates 13a and 13b that are pivotally mounted to the forward pair of posts 10 located at the entrance of the assembly. In use, one of 10 the gates 13a, 13b is pivoted inwardly while the other gate is pivoted outwardly such that a passageway formed between the gates directs an animal through one of the side exits in the direction of the arrows B and C in Figures 2 and 3 respectively. The gate pivoted inwardly 15 prevents the animal from exiting the assembly via either the forward exit or the opposite side exit.

The guiding gates 13a and 13b are also interconnected by a linkage member 14 that is pivotally connected to each of the guiding gates 13 such that an air 20 or water piston and cylinder arrangement 15 directly acting on one of the gates 13a moves the other guiding gate 13b.

As can be seen in Figures 4 and 5, the linkage member 14 is in the form of an inverted U-shaped member 25 having a base 16 and downwardly extending legs 17 that are positioned on opposite sides of the passageway between the gates 13a and 13b.

The second pair of the gates, identified by reference numeral 18, comprises two return gates 18a and 30 18b that are also pivotally mounted to the forward posts and located on outside of the guiding gates 13. The return gates 18 are also sized to span the gap between the forward posts 10 and the rear posts 11 or a stop member 19 projecting therefrom. The stop member 19 is preferably a 35 flexible cushion that allows an animal to free itself should it become jambed between the posts 11 and the gates 13 and 18.

C:\windows\TEMP\FP19767.doc 17/05/04 As can be seen in Figures 2 and 3, when one of the guiding gate 13 is pivoted outwardly, the guiding gate 13 engages the return gate 18 and pivots the return gate 18 outwardly. When the cylinder arrangement 15 is operated 5 to return the guide gate 13 to a central position to close the side exits (as shown in Figure 1), a biasing spring 20 moves the return gate 18 to a closed position.

Figure 2 and 3 also illustrate that when one of the guiding gates 13 is pivoted outwardly to open one of 10 the side exits, the other guiding gate 18 is pivoted inwardly to direct an animal through the side exit. The return gate 18 located at the outside of the guiding gate 13 that has been pivoted inwardly remains in a closed position under the action of the biasing spring 20. 15 An advantage provided by the return gate 18 is that it provides a barrier against an animal entering the assembly via the side exits when each guiding gate 13a and 13b is pivoted inwardly.

The third pair of gates, identified by reference 20 numeral 21, comprises two pivotally mounted entrance gates 21a and 21b that are aligned to extend laterally across the entrance of the assembly. Each entrance gate 21 includes an air or water driven cylinder and piston arrangement 22 for pivoting each gate. 25 The assembly includes first detecting means located at the entrance of the assembly that can detect when an animal enters the assembly. The detecting means may be in any suitable form including photo-electric sensors 23 that emits an infrared electromagnetic beam 30 transversely across the entrance which is shown in Figures 1 to 3 by dashed line T.

The photo-electric sensor 23 may include a sender unit and a receiver unit that are mounted on the forward posts 10a and 10b so that a beam is transmitted across the 35 entrance of the assembly. The photo-electric sensor may alternatively include a sender and receiver unit located Intellectual Property Office of HZ. 23 JUL 20M RECEIVED -lion one post such as post 10a, and a reflector on the opposite post 10b.

The assembly also includes a second detecting means in the form of a photo-electric sensor 24 located on the linkage member 14 located approximately two thirds from the end at which the gates are pivotally mounted to the posts 10. The electromagnetic beam emitted by the sensor 24 is shown as a dashed line S in the Figures 4 and 5.

The linkage member is pivotally mounted to the guiding gates 13 such that the sensor 24 on the opposite sides of the passageway face each other regardless of the position of the guiding gates 13.

In use, when the photo-electric sensor 23 detects that an animal has past through the entrance of the station, the entrance gates 21 can be closed to prevent the animal from exiting the station via the entrance, and in addition, prevent another animal from entering the station prior to the animal in the station exiting the station. The guiding gates 13 can then be operated to open and/or close the side exits so that the animal joins a desired group. When the photo-electric sensor 24 detects that the animal has past through the desired exit, the exit may then be closed and the entrance gates reopened to allow another animal to enter the station. At all stages during operation, the return gates 18 maintain a closed position unless pivoted outwardly by a guiding gate 13, thereby preventing an animal from entering the assembly via an exit.

Advantages provided by this arrangement include: i) when an animal is in the station, the animal can be prevented from backing out through the entrance of the station; ii) when the animal has exited the station, the exits are closed to prevent an animal from entering the station via the exits; and C:\windows\TEMP\FP19767.doc 17/05/04 iii) when the one of the exits of the station have been opened, an animal is prevented from entering the assembly via the other exit.

It will be appreciated by those skilled in the art 5 of the present invention that modifications may be made to the preferred embodiment without departing from the spirit and scope of the invention.

Throughout this specification the terms herd or group have been used interchangeably and are intended to 10 embrace the term mob.

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Claims (31)

- 13 - THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. A device in the form of a station for separating animals into two or more groups, the station capable of 5 being used in association with animal corral or other live-stock holding equipment including vehicles for transporting live-stock, the station including: a) an entrance through which animals can enter the station; 10 b) two or more exits through which the animals can exit the station and thereby be directed into separate groups; c) a first moveable obstruction means that can be operated to selectively open and close the entrance of the 15 station and thereby allow an animal to enter the station; d) a second moveable obstruction means that can be operated to selectively open and close the exits so as to allow an animal to exit the station from one of the exits; e) a first detecting means for detecting when an 20 animal has entered the station by passing through the entrance; and f) a second detecting means for detecting when an animal has exited the station by passing through one of the exits. 25

2. The device according to claim 1, whereby when the first detecting means detects that an animal has past through the entrance of the station, the first obstruction means can be closed to prevent the animal from exiting the 30 station via the entrance, and prevent another animal from entering the station prior to the animal in the station exiting the station.

3. The device according to claim 1 or 2, whereby when 35 the second detecting means detects that the animal has past through the desired exit, the respective moveable obstruction means can be operated to close the exit and,

C:\windows\TEMP\FPl9767.doc 17/05/04 - 14 - if desired, the first obstruction means can be operated to re-open the entrance and allow another animal to enter the station.

5 4. The device according to any one of claims 1 to 3, wherein the detecting means is in the form of photoelectric sensor that emits an electromagnetic beam transversely across the entrance and/or the exits. 10 5. The device according to any one of claims 1 to 4, wherein the photo-electric sensors are arranged so that the beam is transmitted between either: i) a sender unit and a receiver unit on opposite sides of the entrance or exits; or 15 ii) a sender and receiver located on the same side of the entrance or exits and a reflector on the opposite side thereof.

6. The device according to claim 4 or 5, whereby when 20 the beam emitted by the sensor(s) has been broken by an animal walking through the beam and the beam is subsequently restored by the animal moving past the beam, the first and/or second detecting means sends a signal to a controller that operates the first and second moveable 25 obstruction means.

7. The device according to any one of claims 1 to 6, wherein two of the exits are oppositely disposed side exits that face each other and the second moveable 30 obstruction means includes a pair of first gates, whereby one of said first gates is operable to open and close each exit, the pair of first gates defining a passageway so that in use, when one of the first gates is pivoted outwardly to open the respective side exit, the other gate 35 can be pivoted inwardly in parallel relationship such that the passageway between the gates directs the animal through the opened exit. C:\windows\TEMP\FP19767.doc 17/05/04 - 15 -

8. The device according to claim 7, wherein the first gates are interconnected by a linkage member such that moving one of the first gates inwardly of the passageway causes the other first gate to move outwardly. 5

9. The device according to claim 8, wherein one of the first gates is pivoted inwardly and outwardly by a pneumatic or hydraulic piston and cylinder arrangement and the other first gate is driven inwardly and outwardly by 10 the interconnecting linkage member.

10. The device according to claim 8 or 9, wherein the linkage member is in the form of an inverted U-shape in which a base extends above the first and second gate 15 members and two legs project downwardly from the base on opposite sides of the passageway defined between the first gate members.

11. The device according to any one of claims 7 to 10, 20 wherein the second detecting means emits an electromagnetic beam across the passageway so as to detect when an animal has past through the exit.

12. The device according to claim 10, wherein the 25 second detecting means is mounted to the legs of the linkage member at a height suitable for detecting when an animal has past through the passageway.

13. The device according to any one of claims 1 to 12, 30 the device further including a pair of second gates, wherein one of the second gates is located on the outside of each of the first gates and is prevented from moving inwardly when the first gate moves inwardly, thereby preventing an animal from entering the station via the 35 exits when the respective first gate has been pivoted inwardly. C:\windows\TEMP\FP197 67.doc 17/05/04 - 16 - 10

14. The device according to any one of claims 1 to 13, including a further exit such that an animal can exit from the station via the further exit when the second obstruction means has closed their respective exits.

15. The apparatus according to any one of claims 1 to 14, wherein the first moveable obstruction means includes a pair of third gates that are aligned side-by-side and extend across the entrance of the station.

16. The apparatus according to any one of claims 1 to 15, wherein each third gate is driven by a pneumatic or hydraulic piston and cylinder mechanism. 15

17. A device in the form of a station for separating animals into two or more groups, the station capable of being used in association with animal corral or other live-stock holding equipment including vehicles for transporting live-stock, the station including: 20 a) an entrance through which animals can enter the station; b) a first moveable obstruction means that can be operated to selectively open and close the entrance of the station and thereby allow an animal to enter the station; 25 c) two exits disposed on opposite sides of the station through which the animals can exit; d) a second moveable obstruction means that includes a pair of first gates, wherein one of the first gates is located at each exit of the station and thereby defines a 30 passageway between the gates for an animal so that in use, when one of the first gates is pivoted outwardly to open one of the exits the other gate can be pivoted inwardly in parallel relationship so as to direct the animal through the opened exit; and 35 e) a pair of second gates, wherein one of the second gates is located on the outside of each of the first gates and is capable of moving outwardly and is prevented from I intellectual Property Office of N.Z. 2 3 JUL 2004 DPfFlVED - 17 - moving inwardly so that when one of the first gates is pivoted outwardly to open its respective exit and the other first gate pivots inwardly, the second gate located on the outside of the inwardly pivoted first gate prevents an animal from entering the device via the respective exit.

18. The apparatus according to claim 17, wherein the apparatus further includes a first detecting means for detecting when an animal has entered the station by passing through the entrance, and a second detecting means for detecting when an animal has exited the station by passing through one of the exits.

19. The apparatus according to claim 18, whereby when the first detecting means detects that an animal has past through the entrance of the station, the first obstruction means can be closed to prevent the animal from exiting the station via the entrance, and prevent another animal from entering the station prior to the animal in the station exiting the station.

20. The apparatus according to claim 18 or 19, wherein the second detecting means detects that the animal has past through the desired exit, the respective moveable obstruction means can be operated to close the exit and, if desired, the first obstruction means can be operated to re-open the entrance and allow another animal to enter the station.

21. The apparatus according to any one of claims 18 to 20, wherein the detecting means is in the form of photoelectric sensors that emits an electromagnetic beam transversely across the entrance and/or the exits. C:\windows\TEMP\FPl97 67.doc 17/05/04 - 18 -

22. The apparatus according to claim 21, wherein the photo-electric sensors are arranged so that the beam is transmitted between either: iii) a sender unit and a receiver unit on opposite 5 sides of the entrance or exits; or iv) a sender and receiver located on the same side of the of the entrance or exits and a reflector on the opposite side thereof. 10

23. The apparatus according to claim 21 or 22, whereby when the beam emitted by the sensor(s) has been broken by an animal walking through the beam and the beam is subsequently restored by the animal moving past the beam, the first and/or second detecting means sends a signal to 15 a controller that operates the first and second moveable obstruction means.

24. The apparatus according to any one of claims 18 to 23, wherein the first gates are interconnected by a 20 linkage member such that pivotal movement of one of the first gates can cause pivotal movement of the other first gate via the linkage member.

25. The apparatus according to claim 24, wherein one 25 of the first gates are pivoted inwardly and outwardly by a pneumatic or hydraulic piston and cylinder arrangement and the other first gate can thus is driven inwardly and outwardly by the interconnecting linkage member. 30

26. The apparatus according to claim 24 or 25, wherein the linkage member has a base that extends between the first gate members and two legs that project downwardly from the base on opposite sides of the passageway defined between the first gate members. 35

27. The apparatus according to any one of claims 18 to 26. wherein the second detecting means emits an c:\wlndows\TEMP\FP19767.doc 17/05/04 - 19 - electromagnetic beam across the passageway so as to detect when an animal has past through the exit.

28. The apparatus according to claim 26, wherein the 5 second detecting means is mounted to the legs of the linkage member at a height suitable for directed when an animal has past through the passageway.

29. The apparatus according to any one of claims 18 to 10 28, wherein the device also includes a further exit and the second moveable obstruction means allows animals to exit from the station via the further exit when the two side exits are closed. 15

30. The apparatus according to any one of claims 18 to 29, wherein the first moveable obstruction means includes a pair of third gates that are aligned side-by-side and extend across the entrance of the station. 20

31. An apparatus substantially as hereinbefore described with reference to the accompanying figures. Paul Shewen & Co Pty Ltd By its Attorneys Intellectual Property Office of NZ \ 9 MAY 2004 ftECElVED C:\windows\TEMP\FP197 67.doc 17/0 5/04 ABSTRACT According to the present invention there is provided a device in the form of a station for separating 5 animals into two or more groups, the station capable of being used in association with animal corral or other live-stock holding equipment including vehicles for transporting live-stock, the station including: a) an entrance through which animals can enter the 10 station; b) two or more exits through which the animals can exit the station and thereby be directed into separate groups; c) a first moveable obstruction means that can be 15 operated to selectively open and close the entrance of the station and thereby allow an animal to enter the station; d) a second moveable obstruction means that can be operated to selectively open and close the exits so as to allow an animal to exit the station from one of the exits; 20 e) a first detecting means for detecting when an animal has entered the station by passing through the entrance; and f) a second detecting means for detecting when an animal has exited the station by passing through one of 2 5 the exits. Intellectual Property Office of NZ \ 9 MAY 2004 C:\windows\TEMP\FP19767.doc 17/05/04