WO2008006233A1

WO2008006233A1 - Cage door

Info

Publication number: WO2008006233A1
Application number: PCT/CH2007/000328
Authority: WO
Inventors: Reto Burger; Frieder NEUHÄUSSER-WESPY
Original assignee: Newbehavior Ag
Priority date: 2006-07-08
Filing date: 2007-07-06
Publication date: 2008-01-17
Also published as: EP2041386A1

Abstract

A door module (32, 33) for closing a door opening (4) in a test animal cage (1 ) is proposed, the door module meeting the very stringent requirements in terms of animal health and animal welfare and reproducibility of the tests, by the door module ensuring that test animals remain unscathed when the door opening is closed. In the case of the novel door module, a door slide (50) is mounted in a manner such that it is movable linearly up and down in a channel (35). The door slide is coupled by means of magnets to a drivable door-lifting mechanism (60) and is moved to and fro by the latter between a release position and a position for closing the door opening (4). If, when the door opening is closed, the door slide strikes against an obstacle (generally a body part of a test animal) and if, in the process, a maximum force is exceeded, then the magnetic connection is released and the door slide (50) is decoupled from the door-lifting mechanism (60) and drops back in the channel to the lower release position. As a result, the test animals are protected against injuries and the system can automatically reestablish the operational connection. In addition, the contact-free connection between door-lifting mechanism and door slide makes it possible for the channel, in which sugar- and/or protein-containing reward liquids are dispensed, to be encapsulated on all sides and for soiling to be restricted to minimal regions so as to minimize the outlay on cleaning and malfunctions caused by soiling.

Description

CAGE DOOR

The present invention relates to door module for closing a door opening in a test animal cage according to the preamble of claim 1 and a method for operating a door module for closing a door opening in a test animal cage according to the preamble of patent claim.

Although the number of animal experiments in Switzerland has fallen by 75% in the last 20 years, experiments with animal models, especially in biological, medical and pharmaceutical research, remain essential. Intensive research combined with the quantitative reduction led to a massive increase in the quality of the experiments. In order to make the results of animal experiments more meaningful, on the one hand, attempts are made to reduce or exclude negative, uncontrollable influencing factors during the experiments and, on the other hand, to improve the well-being of the animals by improving their posture. In order to achieve the first goal, the anthropogenic influences (noise, vibrations, but also visual, olfactory and other influences) as the main source of interference must be kept as far away as possible from the experimental animals. At the same time it has proved to be extremely advantageous to reduce abnormal behavior by welfare of the experimental animals.

The applicant, under the name of Intellicage®, is simultaneously aware of a system for the standardized performance of animal experiments with up to 16 mice, which gives the experimental animals the opportunity to socialize in a species-appropriate manner during the experiments. These experimental cages allow to offer an approximately human-free environment during the behavioral experiments and thereby eliminate humans as a disruptive factor. The known Intellicage®, as shown in Figure 1, uses the Transponder technology for the identification and individual treatment of each individual test animal in the cage. It allows for a variety of behavioral tests that reward nutrients and punish them with "air puffs." Four study corners 2 are set up in a large standard rat cage 1. The experimental animals can be implanted using transponders when approaching the learning corners. Each lemur 2 is separated from the cage interior by a front wall and comprises a conventional conditioning unit 3 with left and right closable door openings 4, 4 'which can open the mice by noses or lever pressures , 4 ¹ are substantially circular and dimensioned so that only one mouse at a time can stick its head through the opening and thereby obtain a reward in the form of a feed solution Open down into the conditioning 3 can be plugged. The conditioning can be controlled by light emitting diodes in different colors, air blast punishment and sensors such as "lick-o-meters" or infrared motion detectors Depending on the complexity of the learning behavior to be studied, up to 16 mice can be monitored in an Intellicage In the known system, up to 8 Intellicages® can be controlled by one computer, and the system can be operated continuously for days or weeks, usually requiring cleaning once a week The high level of "intellectual enrichment" in the experiments not only positively affects the behavior of the animals, but the Intellicage® also leads to a significant reduction of repetitive and boring Ar work for laboratory technicians and researchers.

The structure of the known Lerπecken 2 will now be explained in more detail with reference to the figures I b to I d. In the figure I d is a single learning corner 2 in a view of the Front of a front wall 6 shown as seen by experimental animal in the cage. The two bottles 5 with the reward liquid are usually not visible to the experimental animals, but hidden by the cage lid. In the front wall is an inlet opening 7, in which an annular transponder antenna is integrated, through which the experimental animals individually in a conditioning chamber of the learning corner 2 can slip. The conditioning chamber 8, which is visible obliquely from below in FIG. 1b, has a right-angled triangular crack and is separated from the front wall 6 (omitted in FIGS. 1b and 1c), a cover plate 9, a bottom 10 and two at right angles to one another arranged side walls 1 1, 12 defined. The bottom 10 forms a grid which is on the side walls 1 1, 12 with the door openings 4, 4 'releasably secured. In the cover plate 9, two tubes 13 are arranged for receiving drinking tubes of the liquid container. The tubes 13 are positioned so that the drinking tubes open with inserted bottles in the area behind the door openings 4, so that they are easily accessible to the experimental animals with the door open. The door openings 4 can be opened and closed automatically with a closure plate 14. In the figure 1 c, a closed first door opening on the left side and an opened second door opening 4 are shown on the right side in a view of the back of the conditioning unit. The two closing mechanisms including the closure plates 14 are constructed essentially mirror-symmetrical. The closure plates 14, 14 'are rotatably mounted on an axle journal 15 at one end and have at the opposite end head ends 16, 16, 16' with a circular sector-shaped external toothing 17, 17 '. By stepper motors, which in each case via a drive wheel 18 in the teeth 17, 17 'of the head ends 16, 16' engage, the closure plates 14, 14 'between an upper closed (left closure plate 14) and a lower open position (right closure plate 14th ') to move back and fourth. A stop pin 19 passes through a circular sector-shaped oblong hole 20 in the head region of the closure plates and restricts the rotational movement of the closure plates to the sector between the two end positions. To create space for the stepper motor 21, the closure plates 14, 14 'in one central area in which they cover the door openings each U-shaped bent forward. The two closure plates 14, 14 'are therefore not usable interchangeable with each other only usable for one side.

If the left door opening, which is shown closed in the figure I b, are opened, the stepper motor 21 is driven by the parent control system and rotates the drive wheel 18 in a clockwise direction until the stop pin 19 comes to rest at the upper end of the slot 20. In this position, the closure plate 14 completely clears the door opening and a test animal has access to the reward fluid. This door position is shown in the figure I c for the right door opening 4 'in a view obliquely from below, in which the mouth opening 22 of the tube 13 is visible. After a predetermined time by the parent control system, the door opening is closed by driving the stepping motor and the resulting rotation of the drive wheel in the reverse direction again. When closing, the closure plate presses against the snout of the test animal to cause it to withdraw from the opening and stop drinking. The control electronics are programmed on the Intellicage® to try eight times to swing the locking plate in front of the door opening. If the system registers a resistance above a defined threshold when swiveling, the closing plate is partially swung back and a new closing attempt is started. After eight unsuccessful attempts to close the door opening, the closure plate is brought into the open position and remains there. The force exerted on the snout of a test animal by the closing plate in the area of the door opening is limited to 50 to 250 g in the sense of "animal welfare". In any case, it must be avoided that there is bruising of the nose or even open injuries However, there are always experimental animals that have learned to accept the eight-time pressure and then indefinitely take up reward liquid with the door open.If the closure plate locked after unsuccessful closing attempts in an upper position, it could just happen in rats and mice as experimental animals that the animal is captured by hanging it with the gnawed teeth and can not retreat.

Many experiments use reward fluids with high sugar and / or high protein content. Ingesting the reward liquids by the animals and by dripping often leads to contamination in the door area and in the back area of the learning corner. In particular, the dirt in the door area can lead to sticking of the closure plates with the backs of the door opening. This brakes the locking plates or blocks them completely. Such malfunctions lead to increased cleaning and or maintenance and correspondingly higher costs. Dirt on the stepper motor and gear drive cause even more cleaning effort. Both types of contamination can affect and distort the transmission of force to the closure plate. This unintentionally influences the standardized conditions of the experimental procedure.

It is therefore the object of the present invention to provide a device for closing a door opening in a laboratory animal cage and a method for operating such a device, which do not have the abovementioned disadvantages.

This object is achieved by a door module for closing a door opening in a laboratory animal cage according to claim 1 and by a method for operating the door module for closing a door opening in a test animal cage according to claim 9.

Preferred embodiments of the device according to the invention and of the method according to the invention emerge from the respective dependent claims. In the drawings, various embodiments of the device according to the invention are illustrated and explained in the following description. It shows:

1 a shows a known test animal cage of the brand Intellicage® with four learning corners in a perspective view obliquely from above,

Figure 1 b shows a view of a back side of a known conditioning unit of a learning corner of the cage according to Figure I a ₁

FIG. 1 c is a view from below, at the bottom right, of a conditioning unit according to FIG.

FIG. 1 d shows a view of a front wall of a learning corner with a conditioning unit mounted on the back from a cage according to FIG. _{1 a}

FIG. 2 a shows a side view of a back side of a learning corner with a conditioning unit with a view of a first left-hand closing device according to the present invention,

FIG. 2b shows a view of a front wall of a learning corner with a conditioning unit mounted on the back according to FIG. 2a,

2c shows a perspective view of the learning corner according to FIG. 2a from the top right, with a view of a second right-hand closing device, FIG.

2d shows a view from above of the learning corner according to FIG. 2a, FIG. 3a shows a perspective view from the top right onto a door module of a left side of a conditioning unit according to FIG. 2a from the upper right, wherein a separating disk has been omitted in order to reveal the view of an inner channel;

FIG. 3b shows a view of the rear side of the door module according to FIG. 3a,

3c shows a view of the rear side of the door module according to FIG. 3a, FIG.

Figure 4a is a perspective view of one on a door lifter according to a preferred embodiment, with a magnet omitted to reveal the view of a socket;

FIG. 4b shows a side view of the door lifter according to FIG. 4a,

FIG. 4c shows a top view of the door lifter according to FIG. 4a,

Figure 5a is a perspective view of the back of a door carriage according to a preferred embodiment;

FIG. 5b shows a view of the front side of the door slide according to FIG. 5a,

5c is a top view of the door carriage according to FIG 5a,

Figure 5d is a view of the back of the door slide according to Figure 5a, and

FIG. 5e shows a side view of a door slide according to FIG. 5a An essential aspect of the present invention is that the connection between the means for closing the door opening and the drive is decoupled. In the preferred embodiment, the connection is magnetic. This releasable connection makes it possible to shield the area of the device, which is most susceptible to soiling, from the rest of the learning corner, or to completely separate each of the means for closing the door opening by a separating element, while at the same time maintaining the operative connection between these means.

It has been shown that the construction with a free center bar

FIG. 2 a shows a side view of a back side of a learning corner 30 with a conditioning unit 31 with a view of a first left-hand closing device 25 according to a first embodiment of the present invention. The basic structure of the learning corner 30 with front wall 6, conditioning unit 31 and containers 5 with reward liquid, does not differ significantly from the known and described above Lernecken 2. Instead of the above-described open design of the closing mechanisms on the backs of the side walls 1 1, 12 include new closing devices 25 door modules 32, 33 in which the pollution with reward ungsfüssigkeit remains limited to an internal vertical channel 35 in a closure housing 34. The interior of the channel 35 is not visible in the figure 2a, since it is covered by an opaque blade 36. The cutting disc 36 is inserted from below into guide grooves 38 in a rear wall 39 of the closure housing 34 and releasably held at an upper end with a locking mechanism 37 in the retracted position. From Figure 3, in which the cutting disc 36 'is shown in a transparent embodiment, it is clear that a door carriage 50 up and down-displaceable in the channel 35 is arranged. The cutting disc 36 'forms the rear wall of the rectangular cross-section channel 35 wherein the three further side walls are formed by inner walls of the closure housing, wherein The channel is preferably open at the bottom and has at the top a tube 47 for receiving a drinking tube 48 of the liquid container 5 on the front inner wall 40 has an opening 41 which is configured approximately congruent to the actual door opening. The tube is placed approximately centrally to the channel cross section, so that the drinking tube end can open behind the door opening. In FIG. 3b, the door slide 50 is in a lower position and completely clears the opening 41 or the door opening. A lateral stop 42 limits the sliding mobility of the door slide in the channel down. However, the door carriage 50 is held and moved by means of a door lifter 60, which engages with a head end 61 to the left of the channel on a drive wheel 18 of a stepping motor completely sunk in the shutter housing 34. On the opposite side of the channel 35, a stub axle 43 is arranged at approximately the same height, on which the door lifter with a foot 62 is slidably mounted. A cover plate 44 prevents the axle journal 43, fixes the door lifter 60 in the axial direction on the journal 43. The head and foot ends are connected to each other by a flat arm 64 which is approximately in the middle on both sides with sockets 65, 65 'for magnets 66, 66'. is provided. The head end 61 of the door lifter 60 is in turn provided with a circular sector-shaped external toothing 67 which acts on the drive wheel 18. By turning the drive wheel 18 in the clockwise direction, the door lifter is pivoted down until the arm 64 abuts with a lower edge on the stop pin 45, as shown in Figures 3a and 3b. If the drive wheel 18 is rotated clockwise by the stepper motor, then the arm pivots upwards. Since the door slide 50 is provided on a rear side with an oppositely poled magnet, it is entrained in the linear upward movement of the door lifter 60 by the attraction of the magnets. The magnets are strong enough that the active compound breaks through the cutting disc only at a force of 50 to 250 grams. The weight of the door slide is therefore hardly significant. The magnetic operative connection between door lift 60 and door slide 50 is not rigid, but causes the impact of the door slide on an obstacle, for example, on the nose of a test animal, a cushioning. This represents the meaning IC

animal health, that the force exerted on closing the door opening can not exceed an upper limit. In extreme cases, the connection is released, the support arm pivots upward and the door slide 50 falls back to the lower position on the stop 42. By means of a position control of the door slide, which will be discussed in more detail below, the system can determine whether the carriage 50 is actually in an upper closing position when the support arm is in a corresponding upper position, wherein the position of the support arm 60 on the position of the stepper motor is determined. If it is determined that the carriage has been lost, the control system pivots the support arm back down to recapture the carriage, ie to restore the magnetic engagement.

From the figure 4 it is apparent that the circular sector-shaped external toothing 67 is arranged at the head end 61 on a circle which has its center M at the foot end of the door lifter at the pivot point M exactly between the tongues 63. The tongues 63 enclose in the assembled state, the journal 43, the connection can be solved easily by hand and without tools. Since the cutting disk 33 for removing the door slide 50 from the channel 35 can be easily removed by hand, the disassembly for cleaning or maintenance is fast, easy and without tools at any time.

From the figure 4c it is clear that the door lifter is constructed according to a preferred embodiment symmetrical to the plane S. If both sockets 65, 65 'are provided with magnets 66, 66', the door lifter can be used on both sides, that is to say both in left-hand and right-hand door modules 31, 32. In FIGS. 2a and 2c, one-sided left and right door holders 60 'and 60 "according to a further embodiment are shown, which are provided with magnets only on their respective inner sides of the arms which face the separating disk and thus the door carriage. In a further preferred embodiment of the invention, which is not shown in the figures, the magnets are not fixedly attached to the arm of the door lifter, but they are rotatably mounted, and thereby optimally aligned during the pivoting movement at any time on the Cegen magnet in the door carriage ,

The magnets of the door lifter and door slide are preferably so far sunk in their respective versions, that only the plastic material of the edge beads of the sockets rests against the blade and rubs when moving to her. This ensures that the cutting disc is not scratched and the view from the outside to the door opening remains undisturbed for as long as possible. Alternatively, the magnet can also be coated or even injected to avoid unnecessary friction. The friction can be further reduced with a suitable choice of material. Thus, door lifters and carriages are preferably made of the high-grade plastic material POM (polyoxymethylene), which has teflon-like properties. As a general rule, all materials which come into contact with the reward liquids and / or the animals should preferably be used for those materials which are hygienic and easy to clean.

FIG. 5 shows a door slide 50 according to a preferred embodiment in various views. A front door plate 51 is connected via a centrally arranged web 53 with a rear rear wall 52. When installed, the door slide 50 is guided with little play in the channel 35, the door plate carries lateral guide ribs 56, 57, as well as each contribute a few upper and lower runners 58 of the rear wall 52 for better guidance in the channel. The runners 58 minimize the friction surface with which the door slide 50 rests against the cutting disc 36 and stabilize it laterally against the channel inner walls. The height of the rear wall in the preferred embodiment is more than 1.5 times the channel width. The rear wall 52 is thus substantially higher than the door leaf 51. The skids 58 are arranged in the lateral corner regions of the rear wall to fully exploit the size of the rear wall and a lateral Tilting or jamming of the carriage 50 in the channel 35 to prevent. The skids 58, which extend from the rear wall 52 to the sides and rearwardly towards the cutting disc are higher than the socket 55 for the approximately in the center of the rear wall 53 arranged holding magnet 46. This in turn prevents the magnet 46 at the Cutting disc 36 rubs.

In the view according to FIG. 5c from above onto the door slide 50, it can be seen that in each case a position magnet 54 in the form of a magnetic pin is embedded in the lateral guide ribs 56, 57. If the door carriage is in an upper position in the channel, then the position magnets 54 lie directly below two sensors which are arranged in or above the top wall of the channel and signal without contact that the door opening is completely closed. If this signal is missing even though the door lifter is in the upper position, the system recognizes that the magnetic connection door lifter 60 and door carriage 50 has come loose and the door opening is open. In this case, the arm is pivoted to the lower position and the slide, as previously described, coupled again to the arm.

In the figure 3c is indicated that the web 53 is arranged between the door plate 51 and the rear wall 53 that it comes to rest with built-slide door 50 in the channel under the tube 47, respectively under the drinking tube of the liquid container. If, for example, the dripping liquid drips when the door is closed, the drops fall on the web 53, which acts as a drip catcher. The drops of liquid run along the web and drop off in the area of a lower drip edge 59 in a controlled manner from the door slide, without contaminating the channel inner walls or the separating disk. The poorly wettable POM material of the door slide 50 means that even sticky liquids can barely settle, but bead off and drop to the bottom of the learning corner, where they are removed during regular cleaning or collected in a collecting vessel. The web 53 does not extend over the full height of door plate 51 and rear wall 53. The upper portion is recessed to - as indicated in Figure 5e - in the upper Verschliessstellung space for a drinking straw 48 shown in dashed lines to offer.

In a preferred embodiment of the device according to the invention, the channel is provided with a flushing device, which preferably sprays a cleaning solution through one or more nozzles in the duct ceiling when the door is closed in order to loosen and rinse off contaminants. In the embodiments with automatic irrigation, which are not shown in the figures, a drainage or a drain for the rinsing liquid is preferably arranged at the bottom of the learning corner.

In order to be able to meet the increasing demands on "Animal Health" and "Animal Weifare" also in the future, in addition to the already described safety measures that the test animals remain intact, provided in further advantageous embodiments, a force control on the stepper motor, so that the closing force in dependence can be varied from a number of selectable parameters to the maximum force.

The individual transponder identification of the animals allows the system to regulate the force of the closing mechanism depending on the type of animal (gender, age, etc.) or individually on the individual animal. Thus, the door opening is released not only for reward, after the animal clearly identified by its transponder has fulfilled its dynamically assigned learning task, but it is possible after receiving a certain amount of reward liquid the door with an individually adjusted force or after a customized flow closed. The individual leaking movements of the animal ("licks") at the delivery opening of the reward fluid are preferably detected by the electronics not continuously but in packets (ie after 10 or 50 licks) and transmitted to the higher-level system. The higher-level system can then send the signal to the. Due to the recorded liquid volume Send close to the stepper motor. The number of closing attempts, their frequency, as well as the force with which the slide is moved up in each attempt, can be varied individually by the superordinate system as required.

Due to the magnetic operative connection between door lifter and door slide, the impact is damped elastically when hitting an obstacle (usually the nose of the test animal). In accordance with a preferred embodiment, the system controller ensures that in such a case the closing movement is stopped, the door lifter pivots back a bit and a new closing attempt is made. If the system detects that the door has not been properly closed, attempts are made to close the door using various strategies, always taking into account that the animal is not injured or trapped.

The door opening can also be closed for the following reasons, depending on the pet's individual learning program:

i) the test animal retracts before receiving the assigned volume of fluid and door closes so that no other animal finds the open door.

ii) the experimental animal is limited to the time available to receive the reward; after the individual time available for the animal, the door is closed.

The new procedure, when closing the door opening, ensures that it is completely closed and that the test animals are not injured or caught. List of reference numbers

1 experimental cage

2 learning corner

3 conditioning unit

4 door opening

5 containers

6 front wall

7 inlet opening

8 conditioning chamber

9 cover plate

10 floor

11 sidewall

12 side wall

13 tubes

14 closure plate

15 axle journals

16 head end

17 external teeth

18 drive wheel

19 stop pin

20 slot

21 stepper motor

25 closing devices

30 learning corner

31 conditioning unit

32 left door module

33 right door module

34 lock housing

35 channel

36 cutting disc

37 locking mechanism

38 guide grooves

39 rear wall

40 front inner wall

41 opening

42 stop

43 axle journals

44 lens

45 stop pin

46 holding magnet

47 tubes

48 drinking tube

50 door slides

51 door leaf

52 rear wall

53 footbridge

54 position magnets

55 magnetic socket 56 lateral guide rib

57 lateral guide rib

58 skids

59 drip edge

60 door lift

61 headboard

62 feet end

63 spring tongues

64 arm

65, 65 'magnetic socket

66, 66 'magnet

Claims

claims

A door module (32, 33) for closing a door opening (4) in a test animal cage (1) comprising a movably mounted closing means (50) which is controlled by a drive (18, 21) between a release position and a position for closing the door opening (4 ) is movable back and forth, characterized in that the power transmission from the drive to the closure means (50) takes place at least at one point completely by means of a releasable magnetic operative connection.

2 door module (32, 33) according to claim 1, characterized in that the closure means is a movably mounted door slide (50) with a holding magnet (46) to a corresponding magnet (66, 66 ') of a driven by the drive unit door lifter ( 60, 60 ', 60 ") is coupled.

3 door module (32, 33) according to claim 1 or 2, characterized in that the

Door slide in a channel (35) of a closure housing (34) is guided linearly movable, so that the pivoting movement of the door lifter (60, 60 ', 60 ") is converted into a linear movement of the door carriage.

4 door module (32, 33) according to claim 3, characterized in that three side walls and a ceiling of the channel (35) of inner walls of the

Enclosed housing are formed, and a removable separating disc (35) forms the fourth side wall of the channel, wherein the separating disc (35) between the

Magnets of door carriage (50) and door lifter (60, 60 ', 60 ") is arranged. Door module (32, 33) according to one of the preceding claims, characterized in that the door carriage (50) comprises front door plate (51) for closing the door opening (4), which has a centrally arranged web (53) with a rear rear wall (52). is connected, wherein the web in the installed state below a discharge opening of a drinking tube (48) is arranged to act as a drip.

Door module (32, 33) according to claim 5, characterized in that the rear wall (52) of the door slide (50) is provided with at least a pair of upper and lower skids (58) which abut the channel walls for better lateral guidance and the Minimize the friction surface with which the door slide (50) rests against the cutting disc (36).

Door module (32, 33) according to one of claims 3 to 6, characterized in that in the channel (35) a rinsing system is arranged.

Door module (32, 33) according to any one of the preceding claims, characterized in that the force exerted by the drive (18, 21) on the closure means (50) during closure of the door opening (4) is adjustable.

A method for operating a door module for closing a door opening in a test animal cage, characterized in that a movably mounted locking means (50), by a drive (18, 21) between a release position and a position for closing the

Door opening (4) is reciprocally movable, wherein the power transmission from the drive to the closure means (50) at least at one point completely means a detachable magnetic operative connection, characterized in that a release of the magnetic operative connection is recognized by the door module and / or a higher-level control system and the connection is restored in a subsequent step.

A method according to claim 8, characterized in that based on an individual transponder identification of the experimental animals, the number of closing attempts, their frequency and / or the force with which the closure means is moved upwards in each attempt, is individually variable by the superordinate system.