Device for measuring the gastric pressure and the gastric motility of a livestock animal

Abstract

The invention relates to a device for permanently detecting the gastric pressure, the gastric temperature, the gastric motility and the movement of a livestock animal, in particular a ruminant, comprising a, for example, bolus-shaped body (14), said body (14) comprising the following components: a pressure sensor (9), a telemetric device (9) for transmitting measuring values, and a gas-tight interior space (12), wherein a wall of the gas-tight interior space (12) comprises in some regions an elastic material which is deformable by the gastric pressure of a livestock animal, and wherein the pressure sensor (9) is designed to detect the pressure in the gas-tight interior space (12). According to the invention, said device is designed such that it permanently remains in the stomach of the livestock animal when it is applied to the livestock animal.

Claims

1. A device for detecting the gastric pressure of an animal, in particular of a ruminant, the device comprising: a first subbody and a second subbody, wherein the first subbody is connected to the second subbody via a joint, wherein the device has a position sensor which is designed to determine the relative position of the first subbody to the second subbody, wherein the first subbody in particular comprising: a body (14) having the following components: a pressure sensor (9), a telemetric device (8) for transmitting measured values from the pressure sensor (9), a gas-tight interior (12), one wall (12a) of the gas-tight interior (12) having a resilient region (5, 13) which is deformable by the gastric pressure of the animal, and the pressure sensor (9) being configured to detect the pressure in the gas-tight interior (12), wherein the body (14) of the device is constructed in such a way that it permanently remains in the stomach of the animal When it has been administered to the animal, wherein the device comprises a motion sensor, wherein the motion sensor is designed to detect the movement activity of the animal.

2. The device according to claim 1, wherein the body (14) has an average density of greater than 2.3 g/cm.sup.3 and in particular less than 3.5 g/cm.sup.3, wherein the density is particularly preferably 2.8 g/cm.sup.3.

3. The device according to claim 1, wherein the body (14) has a volume of between 50 cm.sup.3 and 250 cm.sup.3, preferably between 70 cm.sup.3 and 160 cm.sup.3, wherein the volume particularly preferably amounts to 150 cm.sup.3.

4. The device according to claim 1, wherein the region (5) is configured as a resilient membrane (5).

5. The device according to claim 1, wherein said region of the wall (12a) of the gas-tight interior (12) is formed by a resilient hollow body (13) projecting out from the body (14), wherein the hollow body (13) is deformable by forces acting thereon in the stomach of the animal.

6. The device according to claim 4, wherein the membrane (5) or the hollow body (13) can be fixed to the body (14) by means of an annular sealing cap (6).

7. The device according to claim 5, wherein the hollow body (13) can be flexed by forces which arise from movements of the stomach of the animal and wherein the hollow body (13) is provided and configured to be flexed by said forces.

8. The device according to claim 5, wherein the hollow body (13) is of tubular, in particular cylindrical, configuration.

9. The device according to claim 1, wherein the device has a temperature sensor which is designed to detect a gastric temperature in the animal when the device is arranged in the stomach of the animal.

10. The device according to claim 1, wherein the telemetric device (8) is designed to process the measurement data of the pressure sensor (9) and in particular the measurement data of the temperature sensor and/or the motion sensor and to send the processed data to a receiver.

11. The device according to claim 1, wherein the body (14) has a microcontroller (10) and a data memory (11) in which the measurement data or the processed measurement data can be stored.

12. The device according to claim 1, wherein the body (14) has a first region (101) and a second region (102), wherein the first region (101) of the body (14) is radio wave transmissive and wherein the second region (102) is additionally constructed such that the body (14) has at least the average density.

13. The device according to claim 12, wherein the first region (101) has an in particular cylindrical casing (7) of a biocompatible polymer, wherein the telemetric device (8) is arranged in the first region (101) and wherein the pressure sensor (9) is arranged at an upper end of the first region (101), wherein in particular the hollow body (13) adjoins the upper end of the first region (101) and at least in part bounds the gas-tight interior (12), or wherein in particular the upper region (101) is closed at the upper end by the membrane (5) which at least in part bounds the gas-tight interior (12).

14. The device according to claim 12, wherein the second region (102) has an in particular cylindrical casing (1) which has a bottom on an underside of the first region (101), wherein the casing (1) in particular includes stainless steel and wherein the casing (1) comprises a receptacle for an energy source (2) for the telemetric device (9), wherein the energy source (2) may in particular be a primary or a rechargeable battery.

15. A method for measuring gastric pressure using a device according to claim 1 having the steps of: orally introducing the device into the stomach of the livestock animal in such a manner that the device remains permanently in the stomach of the livestock animal, measuring a time series of the pressure, transmitting the measurement data out from the stomach of the livestock animal.

16. The device according to claim 1, wherein the motion sensor has an acceleration sensor.

17. The device according to claim 1, wherein the motion is sensor is completely integrated in the device.

Description

(1) Further features and advantages of the invention are explained below on the basis of the description of figures of exemplary embodiments in which:

(2) FIG. 1 shows two sectional views through a device according to the invention;

(3) FIG. 2 shows a sectional view through a device according to the invention with a hollow body, and

(4) FIG. 3 shows a sectional view of a modification of the embodiment according to FIG. 1.

(5) FIG. 1 shows two sectional views of a device according to the invention. The device has a body 14 in particular in bolus form, also optionally denoted bolus for short. The body 14 is subdivided into a first region or portion 101 and second region or portion 102. The first region 101 has a cylindrical casing 7 of POM. The casing 7 here comprises a packing piece 3, in which the electronics 4 of the body 14 are arranged. Selection of the polymer ensures on the one hand radio wave transmissibility and simultaneously on the other hand biocompatibility of the material.

(6) The electronics 4 here comprise inter alia a telemetric device 8, a pressure sensor 9 and a microcontroller 10 and a memory device 11. The pressure-sensitive part of the pressure sensor is accommodated in a gas-tight interior 12 (or can communicate therewith), the wall 12a of which is at least in part likewise configured from the casing 7 of the first region 101 and the top of which (also part of the wall) is formed by a resilient membrane 5 of silicone rubber. The gas-tight interior 12 is here located at one end of the first region 101 of the body 14 and is preferably arranged on the end face of the elongate body 14.

(7) Deformation of the membrane 5 as a result of application of force brings about a change in pressure in the gas-tight interior 12 which can be detected by the pressure sensor 9. The interior 12 is closed with a closure means in the form of a ring 6 which fixes the membrane 5 in place. The interior 12 is thus sealed in gas-tight manner. The electronics 4 are internally interconnected in such a way that the measurement data from the pressure sensor 9 can be processed by the microcontroller 10, stored on the memory device 11 and sent by the telemetric device 8 to an external base station. The measurement data can furthermore also be processed by the telemetric device 8 itself.

(8) The second region 102 of the body 14 adjoins below the first region 101. The second region 102 has a cylindrical casing 1 (for example of a stainless steel) which comprises an energy source in the form of a battery 2 for supplying the electronics 4.

(9) The electronics 4 are activated by means of a latching circuit which is triggered with a reed contact. To this end, a magnet closes the reed contact from outside and so activates the electronics 4.

(10) The electronics 4 can turn back off as a result of an appropriate level on reset of the latching circuit, so enabling a test run of the entire body 14 or device.

(11) In contrast with FIG. 1, FIG. 2 shows a variant of the invention in which, instead of the resilient membrane 5, a resilient hollow body 13, for example of silicone rubber, projecting out from the body 14 forms or bounds the gas-tight interior 12 or a part of said interior 12. The hollow body 13 is here configured as a probe which can particularly advantageously detect the gastric motility of a livestock animal because it is preferably embodied such that it can be flexed. All the other components are arranged or configured in a similar manner to the features already shown in FIG. 1.

(12) FIG. 3 shows a further configuration of the sensor system. The figure shows the casing 1, which protectively encloses the energy source 2, the packing piece or alternatively weighting body 3, the electronics 4, the flexible membrane 5, together with the sealing cap 6, the casing 7, the telemetric device 8, the pressure sensor 9, as well as the microcontroller 10 and the memory device 11, and the gas-tight interior 12.

(13) In contrast with FIG. 1, the closure means 6 is here configured as an annular sealing cap 6 which is configured to be screwed together with the body 14, in particular the casing 7, wherein the membrane 5 is fixed in place over the interior 12. To this end, the closure means 6, when screwed together as intended with the body 14 or casing 7, presses the membrane 5 against a circumferential contact surface of the casing 7, wherein the membrane 5 is fixed to the body 14 or casing 7 and the interior 12 is sealed in gas-tight manner.

(14) In particular, in an embodiment with a circumferential region, said annular sealing cap 6 presses against a circumferential edge region of the in particular circular membrane 5. The membrane 5 does not here project beyond the sealing cap 6 in the axial direction of the body 14, as a result of which the membrane 5 is provided with additional protection.

(15) Further Development of the Invention

(16) A further development of the invention is outlined below.

(17) The period of operation of devices which require electrical current to function is limited for technical reasons (for example if the energy is supplied via a mobile energy storage device, for example a primary or a rechargeable battery). Long-term measurements in which the device, which may be a sensor or a sensor system, is accommodated in a living organism, such as for example a cow, naturally allow no ongoing physical access to the device.

(18) Replacement of the energy supply in order to maintain the measurement task is then ruled out. In particular in ruminal boli [OE 600 17 916 T2] [WO 2011/079338 A2] [GB 2 455 700 A], in which the bolus is activated and then introduced orally into the rumen preferably of cows, it is no longer possible to exchange the bolus once it has been introduced in order to change the battery or sensor.

(19) One unsatisfactory solution to this problem is to repeatedly administer a new bolus which has the disadvantage that this can only be done a limited number of times per living organism or individual animal. Replacement of an exhausted supply of active substance or an exchange in the event of malfunction has also not hitherto been possible. This problem is addressed by the further development of the invention.

(20) In addition, reuse of the device by establishing a cycle in which the device is reprocessed would provide a sustainable and economically viable way of keeping costs low.

(21) Increasing concerns regarding environmental protection would also be addressed by such planned handling of resources.

(22) Object of the Further Development of the Invention

(23) The field of application of the device is health monitoring or the administration of active substances to living organisms, preferably livestock. Since the device is exchangeable, the periods of operation are limited only by the possibility of exchanging the device.

(24) Ruminal boli, as are for example used in cows for pH measurements in the rumen [OE 600 17 916 T2] [WO 2011/079338 A2] [GB 2 455 700 A], must have a minimum density of 2.3 g/cm.sup.3 for them to remain permanently in the reticulum (rumen). If the density is lower, such boli move onward in the digestive tract and ultimately leave it naturally and are excreted.

(25) Accordingly, if such a sensor has the required minimum density on introduction or during operation and, in response to a specific signal, reduces its density or mass, a device is obtained which can remove itself as desired from the body via a natural pathway. Said device can then be replaced, ideally seamlessly, with a new one.

(26) In a preferred embodiment, the change to the device can proceed by moving a piston which expels a solution present in the bolus. The consequence of this expulsion of a solution by piston movement would be a reduction in the total weight of the bolus. The device would experience additional buoyancy as a result of the change in volume or pressure of the piston chamber cleared by the piston.

(27) In a further variant of the embodiment, the change to the device can proceed by jettisoning a ballast element.

(28) Discharging a heavy fluid such as for example the non-toxic sodium polytungstate would also result in a reduction in mass. The device becomes correspondingly lighter as a result of each of the listed measures and can be excreted via the natural pathway since it no longer has the required density to remain in place.

(29) A further variant embodiment consists in a gas being formed by initiating a chemical reaction or in gas passing from a pressure vessel into a flexible balloon or compartment, so reducing the density of the device.

(30) The bolus, which is now lighter or has been changed in density, is excreted, whereas when a jettisoned ballast element is used, the latter remains in the reticulum. The aim of these measures is to modify the part of the device to be exchanged or the entire device in such a manner that it no longer meets the conditions for remaining in place in the organ to be investigated.

(31) According to the invention, the device may be used for repeated use in living organisms or preferably in livestock husbandry. It may be equipped with sensors or sensor systems in order, in the digestive system of living organisms, to determine physiological parameters of an organ (for example pressure, temperature, pH, conductivity, movement activity).

(32) These data may furthermore be retrieved or transmitted by telemetry. Furthermore, active substances may alternatively or additionally be delivered in targeted manner by means of a reservoir located in the device.

(33) Exchangeability of the device opens up the possibility of permanent, sensor-controlled administration of an active substance or medication.

(34) The shape of the device is primarily determined by its intended application. In the case of a ruminal bolus, it is accordingly of tube-like and rounded shape and has a conventional length of approx. 10-15 cm with a diameter of approx. 3-4 cm. When used as a ruminal bolus, the density on introduction into the rumen is preferably no less than 2.3-2.5 g/cm.sup.3 so that it will reliably remain therein.

(35) The advantage achieved with the invention consists in the fact that, once a defined limit capacity of the energy supply is reached, the latter can straightforwardly be replaced without further intervention from outside. The energy consumption of the device is thus no longer the limiting factor.

(36) It is likewise advantageous to be able to exchange or replenish a supply of an active substance.

(37) A further significant advantage is that of being able to reprocess part of the device for reuse. According to the invention, this can involve recharging the excreted part of the device in order to put it to renewed use in a cycle.

(38) The possibility of reuse also addresses environmental protection issues.

(39) It is also advantageous that ageing effects or other defects of the sensors used, which are manifested for example in drift in the acquired measured values, are largely avoided.

(40) This further development of the invention can be claimed in complementary manner with the claimed invention or also isolated with the following points, wherein also individual features of the further development of the invention can, insofar as is meaningful, likewise be claimed with the claimed invention.

(41) Point 1w:

(42) The invention relates to a device which is characterized in that, in response to a trigger, it undergoes a modification in its form and or a physical parameter, preferably its density or alternatively or additionally its weight, which is such that said device, when introduced into the gastrointestinal tract of a living organism, leaves the gastrointestinal tract again as a result of the change brought about by the trigger via a natural pathway, i.e. rectally or alternatively also orally.

(43) Point 2w:

(44) The device according to point 1w, characterized in that the mass, density and shape of the device in the initial state, i.e. for remaining in place in the target organ, are designed such that the device does not leave the target organ.

(45) Point 3w:

(46) The device according to point 2w, characterized in that, in response to a trigger, which according to the invention may for example be reaching a threshold voltage of the energy supply or alternatively or additionally another trigger, which results in the form and/or shape or density and optionally mass being modified such that according to the invention the position of the device in the organ in which the device is located is modified as a result of the modification in such a manner that the device leaves the alimentary tract via a natural pathway, either onwards rectally or conversely orally.

(47) Point 4w:

(48) The device according to point 3w, characterized in that the device is equipped with a mechanism which allows a ballast element to be detached from the device or, by movement of a piston, a solution to be expelled from the device or alternatively to fill a volume in the device with a gas or another light medium in order purposefully to modify the mass or density of the device.

(49) Point 5w:

(50) The device according to point 4w, characterized in that the device has a control unit which evaluates system parameters of the device or additionally parameters of sensors connected to the system as a trigger for the procedure stated in claim 4.

(51) Point 6w:

(52) The device according to point 5w, characterized in that the device is equipped with an energy supply which is rechargeable.

(53) Point 7w:

(54) The device according to point 6w, characterized in that the device is biologically compatible and safe for use in living organisms, preferably in livestock husbandry.

(55) Point 8w:

(56) The device according to point 7w, characterized in that the device is capable of delivering active substances from a reservoir in a targeted manner. Active substance delivery may proceed either permanently or in a targeted manner by an open- or closed-loop control circuit. According to the invention, exhaustion of the supply of active substance can be one of the triggers which brings about exchange of the device according to points 1w, 3w and 4w.

(57) Point 9w:

(58) The device according to point 8w, characterized in that the device has a telemetry unit with which it can exchange data with a measuring station.