Background Art The accurate detection of oestrus periods, of interest to farmers, breeders, zoos, and any other parties involved in animal management has been the subject of ongoing historical commercial interest. Numerous systems have been proposed, predominantly for use with domestic cattle, to provide the farmer with an indication of which animals in the herd are currently in heat.

Artificial insemination techniques have removed the complication and expense of requiring the breeding bull to be available precisely at the moment of oestrus.

Artificial insemination is a technique aimed at achieving pregnancy whereby semen is introduced artificially into the body of the uterus, at the time of oestrus (or heat).

The advantages of artificial insemination include the opportunity to choose sires that have a proven and/or desirable trait; elimination of the cost and danger of maintaining bulls on farm; minimising the risk of sexually transmitted diseases and genetic defects, and accumulation of beneficial effects of genetic gain over a number of years. Nevertheless, to ensure fertilisation, insemination must still be performed at the correct time during the cow's menstrual cycle, i. e. during oestrus.

Approximately every 17 to 24 days, a cow only comes into heat for approximately 10 to 12 hours before ovulating for approximately 14 hours afterwards. Ovulation is the ideal instance for artificial insemination. It can be thus seen the optimum time for successful fertilisation is a very small fraction of the cow's oestrus cycle.

It is therefore economically desirable to determine the onset of oestrus accurately.

Otherwise a poor pregnancy rates result, and repeated insemination events must be carried out on a greater number of animals. The large number of cows in typical herds compounds the inefficiencies and expenses inherent in performing multiple inseminations, to overcome the uncertainty of the poor conception rates due to sub- optimal insemination time.

Due to the absence of any naturally occurring unambiguous or easily identifiable external signal that the animal is in heat, numerous techniques have been devised to provide a farmer or the like with such a signal. Historically, the techniques used by farmers for monitoring oestrus have been primitive and essentially limited to a reliance on visual observation (either by direct sighting of mounting activity, through tail paint removal), or through pressure sensitive patches or sensors that are mechanical in nature and/or contain chemicals/dyes.

The techniques used to date have often resulted in unreliable oestrus detection and mating accuracy. Alternative, potentially more accurate technical approaches have been investigated by utilising electronic sensors and/or telecommunication devices for transmitting mounting data. However, commercial usage of such devices has been limited due to the expense, fragility, and inadequate reliability of the components to operate in the harsh environment typically required in farm situations.

Those familiar in the art are aware that these devices are bulky, heavy, expensive, and are prone to mechanical damage and/or being knocked from the subject animal.

The use of electrical transponders is also expensive and cumbersome and inevitably requires repairs and battery replacement.

Attempts have been made to automate heat detection. Unfortunately, such systems are still prone to temperature and mechanical failure/drift and need to be serviced regularly for alignment re-calibration. These systems also require the involvement of a human observer.

One conventional oestrus state detection method is to observe an oestrus state of cattle directly with the naked eye. In this method, the observation must be made at least twice a day with respect to the oestrus state of the cattle to obtain an oestrus observation ratio of 90% or more.

The most widespread observational system is the use of"tail paint", whereby visually distinctive"paint"is applied to the rear hind-quarters of the animal. The"paint" remains on the animal's crown of the tail of the cow (tail-head) unless the animal is in oestrus, thereby prompting other animals to mount the animal in heat and thereby removing/smearing the tail paint. Thus, the absence or notable disturbance of the tail paint on the animal signifies the animal may be in heat.

In a further conventional oestrus state detection method, a frangible tube filled with an ink or dye is attached to the crown of the tail of the cow. If the animal then permits a mounting by another animal, the tube bursts to discharge the ink giving a visible indication of the oestrus status of the animal. Although this method has high detection accuracy, it is still heavily reliant on human observation.

An oestrus state detection method using non-visual detection utilises a switch mounted on a crown of the tail of a cow for the recording of an oestrus state of the cow upon mount permission. A transmitter can be used with this technique to relay information including cow identification to the farmer by appropriate means, however the complexity, expense, and unreliability of device mounting and operation has limited widespread acceptance of the technique.

Identification systems for domestic animals (such as that disclosed in US Patent No.

4,510, 495), which comprise a passive transponder unit attached to the animal, are well-known. In such systems, receiver circuits are provided in the transponder unit for receiving and storing energy from high frequency radio waves. The transponder uses the stored energy to transmit identity information which uniquely identifies the transmitting unit and thereby the domestic animal to which the transponder unit is attached.

In U. S. Patent No. 4,247, 758, a domestic animal such as a dairy cow is provided with a transponder unit which is connected to an electronic counter register powered by a battery for storing the number of signals obtained from a motion detector or sensor. When the animal equipped with the transponder enters a region within the range of radio signals from an interrogation unit, the transponder unit transmits radio signals data relating to the identification number of the domestic animal and the corresponding number of movements made by the animal. The number of animal movements is used as means of determining whether the animal is in oestrus.

European patent EP-B1 0 087 015 discloses a further variant to the device in US Patent No. 4,247, 758 whereby the transponder unit transmits data indicative of the number of counted movements during a given time period exceeding a reference value by a predetermined amount.

US Patent No. 4,618, 861 discloses a transponder unit having a motion sensor and a counter for the number of movements, wherein the electrical supply current is provided by induction from movement of the motion sensor. The energy generated and stored is used for the transmission of information.

The complexity and expense of transponder units incorporating self-generation of the necessary electrical power may be overcome by the use of batteries or other energy storage means. However, a battery has a limited useful lifetime, which is a distinctive disadvantage for identification units. Ideally, identification transponders are able to remain attached to the animal in an operative status for prolonged periods without intervention.

Furthermore, it is necessary for the transmission range of identification transponders to match the intended environment and behavioural characteristics of the animals.

This can be particularly important in the detection of oestrus in cows, since they may graze freely during the non-milking period, being seldom collected together.

Consequently, this places a higher demand on the electrical storage needed to reliably transmit information over such distances, and limits the number of identification transmissions that may be performed.

Such disadvantages associated with powered transponders and other on-animal oestrus identification systems underline the benefits of restricting the use of any electrical power involved in an oestrus detection system to the means of observing oestrus and not to an oestrus indicator attached to each animal.

There are three areas of particular concern in oestrus detection and herd reproduction management.

Firstly, oestrus detection by human observation is considerably labour-intensive (and therefore prohibitively expensive) and often inaccurate. Oestrus monitoring is also difficult to observe with the unaided, untrained human eye, particularly given that many farms are very large and the animals may travel significant distances from a given observation point on a farm. Furthermore, the inherent variations and inconsistencies between human observers have a detrimental effect on the levels of oestrus detection accuracies.

Secondly, prior art attempts at replacing human observation techniques have produced highly complex mechanised and automated devices requiring distribution to each animal resulting in significant capital expense. A further drawback of such oestrus detection devices is that of catastrophic failure due to breakage and/or removal of these highly mechanised or electronically intricate devices. Present techniques do not have the necessary reliability to allow the farmer to entrust these devices to monitor the oestrus state of animals without some human intervention.

Those familiar with herd reproductive management are aware that such reliability issues are unsatisfactory for commercial farm operation.

The third area of concern is that of oestrus-based herd traffic management. In order to achieve successful conception in animals, fertilisation techniques such as artificial insemination, surgical, or via a bull must be performed within a very short timeframe after detection of oestrus and prior to ovulation, within a 24-hour period from the start of oestrus. According to typical practice, cows seen in oestrus during evening observation should be inseminated the following morning, cows seen in oestrus during the morning observation should be inseminated that same day. If an oestrus cycle is missed this can lead to great inefficiencies to the farmer, or for other cases such as the reproductive management of endangered species in captive or non- captive environments, the detection of each oestrus cycle may be critical. Prior art oestrus monitoring techniques involving human observation have failed to provide the necessary functionality to direct animals that are in a state of oestrus for further procedures such as'reproductive management'.

Despite several substantial attempts to address the burden of oestrus detection on farmers and to reduce the inaccuracies of human observation-based techniques, no effective solution has been produced. In particular, none of the above prior art techniques addressed the full spectrum of issues involved in automatic oestrus detection and animal traffic control system.

PCT patent application WO 2004/00158 Williamson, published after the priority date of the present application discloses a means of oestrus detection utilising post- mounting changes in the reflectivity of a patch applied to the animals'hindquarters.

The patch is formed with a reflective base layer at least partially covered by a non- reflective coating which is removed during mounting of the animal. The system also incorporates a digital image capture device to measure the changes in the visual appearance of the patch with respect to a threshold value.

Although Williamson may potentially improve on the accuracy of oestrus detection performed by un-aided sight, it nevertheless introduces the need for an investment in a specific type of digital detection system in conjunction with the associated patches to be placed on the animals. Williamson would be incompatible with conventional tail paint or other widely used types of patches or mounting indicator means systems.

It would be desirable to provide an optical recognition system capable of use with different mounting means indicator systems.

All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinence of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.

It is acknowledged that the term'comprise'may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term'comprise'shall have an inclusive meaning-i. e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term'comprised'or'comprising' is used in relation to one or more steps in a method or process.

It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.

Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

Disclosure of Invention According to one aspect of the present invention there is provided an apparatus for determining oestrus in an animal including ; - a sensor means attachable to an animal and capable of detecting a manifestation indicative of oestrus in said animal ; - an indicator means capable of displaying a first state prior to detection of oestrus by said sensing means and displaying a second state with an altered appearance to said first state after detection of oestrus by said sensor means; - an automated visual detection system capable of detecting said altered appearance remotely from the animal.

According to alternative embodiments, the sensor means and indicator means may be separate or alternatively may relate to different aspects of the same components or mechanism.

As used herein, the term'animal'includes cattle, deer, and other farm stock, though is not necessarily limited to same. The present invention may be utilised with any animal whose oestrus status is of interest and detectable. The present invention is primarily described hereon in with respect to cattle for the sake of clarity and ease of understanding, though it will be understood this is exemplary and not limiting.

Oestrus refers to the period of optimal fertility when a female animal is'in heat'. In many animals oestrus is a distinct period when a detectable physical manifestation occurs. In a herd of cattle, a cow in heat is likely to be mounted by another cow.

Detection of the activity of mounting provides an accurate indication of oestrus.

Alternative indicators may include physiological manifestations such as hormonal changes, pheromone emission and/or external behavioural changes such as an increase in the animal's movements which are known to rise significantly during oestrus.

While there are numerous prior art oestrus identification means, particularly for use with cattle, the interpretation of the visual appearance of the indicator means is usually performed by a human observer, e. g. the farmer. Given the relatively short time span of oestrus and the need for a human to detect and subsequently segregate the animal for insemination, there is significant potential for the optimum instance for artificial insemination to be missed.

According to one embodiment, said activity indicative of oestrus includes mounting of the animal in oestrus by other animals and/or increased animal movement.

In one embodiment, said sensor and indicator means used to detect and indicate mounting is attachable to the hind-quarters of a mounted animal, said sensor means including at least one of; - a visibly distinctive, preferably viscous, substance; - a frangible marker; and/or - an abrasion sensor, wherein said indicator means displays an altered appearance between a first 'undisturbed'state prior to mounting and a second'disturbed'state after mounting.

In an alternative embodiment, said sensor means used to detect mounting is attachable to the hind-quarters of a mounting animal, said sensor means including at least one of; - a pressure sensor; - a thermal sensor; and/or - contact sensor or proximity sensor, wherein said indicator means displays an altered appearance upon receipt of a signal from sensor means sensing a change from between a first 'undisturbed'state prior to mounting and a second'disturbed'state after mounting.

Ina further embodiment, said sensor means is attachable to the groin region of the mounting animal.

Regarding the above-described sensor means in more detail : -A'visibly distinctive substance'includes known"tail paint"systems whereby a suitably distinctive paint-like substance is applied to the rear haunches of the animal in said first state and at least partially removed and/or smeared in said second state during oestrus when the animal is mounted by another animal. It is conversely possible that the tail paint substance is located on the groin area of the mounting animal and a portion is then left on the animal in heat after the mounting activity.

Other variations include the use of different colour substances to provide a distinct contrast with the colour of the animal's skin and variations in the viscosity and/or stability of the substance to avoid drying, flaking or other means by which it may be removed from the animal without being mounted.

-A'frangible marker'including any mechanism where a visible/discernable marker substance (such as dye, ink etc) is contained in a housing or enclosure having a predetermined appearance in said first undisturbed state, whereupon application of pressure during mounting causes the frangible marker to rupture or in some other way release the substance to provides a discernibly altered appearance to form said second state. The marker is attachable to the animal by an adhesive patch or strap or any other suitable means and may include a witness area in a contrasting colour to the marker substance (e. g. a white cloth) across which the marker substance may spread after being released by the mounting animal. The marker substance alternatively include two or more chemicals capable of reacting when mixed to generate heat, fluoresce and/or any other external property giving an appearance in said second state discernable from the undisturbed first state of the marker.

A'pressure sensor'is selected from the group including any mechanical, electro-mechanical and/or electrical pressure sensors, piezoelectric transducers or the like which are other sensors capable of detecting pressure applied by a mounting animal on the mounted animal.

A'thermal sensor'capable of detecting the variation in temperature variations in the mounted animal resulting from mounting by another animal.

An'abrasion sensor'includes any coating or film applied over the external surface of a patch or similar which may be readily scratched or abraded to reveal a contrasting surface finish below.

A'contact'or'proximity'sensor may be a variant of a pressure sensor or a distinct unit capable of simply sensing contact with, or close proximity to, another object, i. e. the mounting animal. Optionally, either a contact or proximity sensor may be used in conjunction with a corresponding co-operating attachment on the mounting animal (preferably the groin region) and being capable of reducing the false readings from non-mounting activities such as birds sitting on the animal's back, rubbing fence posts and so forth. Suitable mechanisms of operation include mechanical, magnetic, electro-magnetic, electro-optical sensors. The co-operating attachment on the mounting animal may be a magnetic or induction coil patch or strip with an identifiable signature to enable the sensor on the mounted animal only to be triggered by definite mounting and eliminate spurious contacts.

It will be appreciated that sensor means such as visibly distinctive substances, frangible markers, or the like also provide an indicator means whereby a mounted animal will display an altered appearance with regard to either the smeared/removed visible substance (tail paint) or the ruptured dye holder in the'disturbed'second state indicating the mounting of the animal. In contrast, other forms of sensor means such as pressure, thermal, abrasion or contact/proximity sensors may not in themselves display any altered appearance after the animal has been mounted and may thus require coupling with a distinct indicator means.

Sensor means detecting non-mounting manifestations of oestrus include motion sensors such as pedometers, olfactory sensors capable of detecting pheromones and/or blood sensors capable of monitoring hormones indicative of oestrus. All the aforementioned sensors would also require a separate indicator means.

As used herein, said indicator means may include any mechanism, display, substance or device whose appearance may be discernibly altered from the detection of mounting by the sensor means. This may include electro-mechanical or electronic displays capable of emitting electro-magnetic radiation including infra-red, visible, ultra-violet emission to indicate mounting has occurred, or alternatively, informative displays, including LEDs, capable of signalling at least one mounting parameter such as frequency of mounting, duration of each mounting, elapsed time since mounting, and any other parameter of interest.

As used herein, the term optical/visual includes any part of the electromagnetic spectrum from infrared to ultraviolet and is not restricted purely to the spectrum visible to the human eye.

According to a preferred embodiment of the present invention, said automated visual detection system comprises a visual sensor and an image processor capable of receiving an image from the visual sensor of said indicator in said first state and/or second state and processing said image in the image processor to determine if a manifestation of oestrus (e. g. mounting) has occurred.

Preferably, said determination of the existence of said manifestation is determined by at least one predetermined criteria.

The image sensor may be any appropriate optical or electro-optical sensor, including an optical, video, a CCD camera (visible or infra-red sensitive), digital camera, thermal imager, photodiode array, photomultiplier array, and/or avalanche photodiode array or the like. The image processor is a computational device able to perform mathematical transformations, image processing, algorithms, selections, sorting and/or any other image processing techniques necessary to determine the presence of said predetermined criteria.

In one embodiment, said predetermined criteria include a comparison of a value of at least one image parameter with a predetermined threshold value.

Preferably, said an image parameter relates to an image of the first state, the second state and/or the difference between the first and second state.

According to a further aspect of the present invention, said image parameter includes shape, colour, contrast, size, texture/pattern, intensity, luminance, temperature, wavelength/frequency and/or any combination or permutation of same.

Thus, the determination of whether mounting has occurred for example may be calculated according to whether the first state image has changed to a significant degree, or whether the image viewed meets the criteria for a second state image, or whether the difference between a first and second stage meets a said predetermined criteria.

As an example using tail paint, the system may specify threshold values for the image parameters of the shape or colour for a region on the animal's hind-quarters to indicate the first undisturbed state where the animal has not been mounted.

Measured image parameters values exceeding these threshold values, i. e. by removal or smearing of the tail paint during mounting are interpreted as indicating the animal may have been mounted and the image is actually a second stage image.

In such a scenario, the specified threshold values may be set by a known lookup table of the range of acceptable shape or colour measurements for different environmental conditions.

In a further example, said second state is defined according to a predetermined increase of fluorescent radiation outputted from the sensor/indicator means in response to excitation by an external light source, or, in a yet further embodiment, said predetermined criteria includes whether the image parameters of thermal emissions intensity from the sensor/indicator means exceeds a known threshold value to indicate two thermo-reactive chemicals segregated in the first stage in the sensor means have reacted upon mixing.

The ability of automated visual detection systems (or'machine vision'systems) to independently determine the oestrus status of the animals removes the need for vigilant human observation. Furthermore, the machine vision systems are more accurate and are not prone to fatigue or distraction.

In particular, the ability of the present invention to utilise existing oestrus detection systems such as tail paint, patches that change colour, produce heat, fluoresce or the like after mounting offers a significant advantage over prior art solutions in terms of cost, flexibility and compatibility. Tail paint in particular is in widespread usage due primarily to its low cost and simplicity of use. The present invention retains these advantages whist adding the aforementioned advantages of automated oestrus detection without the need for a specific type of reflective patch to achieve oestrus detection.

The visual sensor may be located in a variety of locations including configured to scan open grazing areas. However, the present invention is particularly effective if used in conjunction with animal movement management systems. Although modern machine vision systems have the ability to identify items at a distance, the accuracy of recognition is improved if the animal can be presented in the same orientation and at close range, e. g. viewed from above and behind when located in a stock race.

Thus, locations such as milking parlours, drinking or feeding stations or other stock handling systems present beneficial locations for the visual sensor.

According to a yet further aspect of the present invention, said apparatus further includes automated drafting means capable of selectively drafting animals determined by the apparatus as being in oestrus.

Thus, the apparatus may automatically segregate animals for artificial insemination with a far higher degree of fertilisation success, and consequentially, an improved efficiency and cost effectiveness.

Preferably, said apparatus further comprises an animal identification means. The identification of the individual animal enables a record of its prior history to be taken into account (e. g. a history of difficult births, or alerting the farmer/vet that this is the animal's first birth) before insemination occurs.

Preferably, said automated drafting means includes : an entry race; a first exit race; a second exit race and; a control mechanism configured to permit entry of an animal determined as being in oestrus by said system to pass through said first exit race and allow animals not in oestrus to pass through said second exit race.

Consequently, various animal attributes may be recorded by the apparatus to enable customised and automatic herd management practices to be implemented. As an example, a cow already inseminated may be released back into the herd and may pass through the automated drafting means without risk of being re-selected for insemination (even if deemed to have been recently mounted) as the apparatus will recognise the status of the animal and return it to grazing.

According to different aspects of the present invention, said animal identification means may include transponder units, bar codes, ear tags or the like.

According to a further aspect, the present invention provides a method of oestrus detection using the apparatus as hereinbefore described, said method including the steps: providing an animal with said sensor means and an indicator means; remotely detecting the appearance of said indicator means; 'determining the occurrence of oestrus according to the appearance of said indicator means.

According to one embodiment, said remote detection of the appearance of the indicator means detects the presence of at least one of the first stage or the second stage.

In a further embodiment, said remote detection of the occurrence of oestrus is determined by detecting a predetermined change in appearance between said first and second stage.

In yet further embodiments, the occurrence of oestrus is determined by detecting an absence of said first stage, or alternatively by detecting a presence of said second stage.

Brief Description of Drawinas Further aspects of the present invention will become apparent from the following description which is given by way of example only and with reference to the accompanying drawings in which: Figure 1a shows a schematic representation of a sensor and indicator means according to a preferred embodiment of the present invention in a first undisturbed state; Figure 1 b shows the sensor and indicator means of figure 1 a in a second disturbed state; Figure 2a shows a schematic representation of a sensor and indicator means according to a second preferred embodiment of the present invention in a first undisturbed state; Figure 2b shows the sensor and indicator means of figure 2a in a second disturbed state; Figure 3a shows a schematic representation of a sensor and indicator means according to a third preferred embodiment of the present invention in a first undisturbed state; Figure 3b shows the sensor and indicator means of figure 3a in a second disturbed state; Figure 4a shows a schematic representation of a sensor and indicator means according to a fourth preferred embodiment of the present invention in a first undisturbed state; Figure 4b shows the sensor and indicator means of figure 4a in a second disturbed state; Figure 5a shows a schematic representation of a sensor and indicator means according to a fifth preferred embodiment of the present invention in a first undisturbed state; Figure 5b shows the sensor and indicator means of figure 5a in a second disturbed state; Figure 6a shows a schematic representation of a sensor and indicator means according to a sixth preferred embodiment of the present invention in a first undisturbed state; Figure 6b shows the sensor and indicator means of figure 6a in a second disturbed state, and Figure 7 shows a schematic representation of automated drafting means in conjunction with a further preferred embodiment of the present invention.

Figure 8 shows a schematic flow chart representation of the uses of the automated drafting means shown in figure 7, and Figure 9 shows a schematic flow chart representation of an image processing algorithm used in preferred embodiments of the present invention.

Best Modes for Carrying out the Invention Figures 1-7 show the preferred embodiments of the present invention pertaining to an animal oestrus detection and management apparatus or system, said system (1) being comprised generally of a sensor means (2), an indicator means (3) and an automated visual detector system (4) (shown in figure 7). In the embodiments shown in figures 1-7, the sensor means and the indicator means relate to different properties of the same component, though it will be appreciated in further embodiments (not shown), the sensor means (2) may provide a non-visual input of some form to a separate indicator means (3) which thereupon displays an altered appearance in response to said input.

Figures 1-5 show variants of oestrus detection means incorporating a sensor means (2) applied to the caudal region of an animal such as a cow (5) in order to detect manifestations of oestrus such as mounting. During oestrus, the cow (5) will be mounted by other cows in the herd and in doing so will contact the caudal region of the mounted animal (5). Although the preferred embodiments described herein relate to oestrus in cattle, it will be appreciated that the system may be extended to other species and used in non-farming environments such as zoos or wildlife parks as part of organised breeding programs.

Figure 1a-b) shows a schematic representation of the caudal region of a cow (5) located in a stock race or similar (6) enclosure. A sensor and indicator means (2,3) in the form of tail paint (7) is applied to the centre of the rear haunches of the cow (5) either manually or by an automated applicator as the cow (5) passes through an appropriate dispenser (not shown). If the cow (5) comes into heat, it will be mounted by another cow in the herd, during which activity the tail paint (7) will be disturbed or removed as shown in figure 1 b). As the tail paint is produced as a brightly coloured substance, any removal and/or smearing provides a strong visual signal to the farmer that the cow is in heat. Although cheap and in widespread use, tail paint does exhibit certain disadvantages including a potential lack of contrast with the surrounding hide of the cow (5), and the potential of removal and/or spreading by inclement weather and/or non-oestrus related activities of the animal, e. g. rubbing or the like.

Figure 2a-2b shows an alternative embodiment utilising a scratch patch (8) in place of the tail paint (7). The scratch patch (8) is comprised of a self-adhesive underside (to attach to the cow (5) ) and a highly visible intermediate layer covered by a removable film/coating on the upper surface formed in a contrasting colour to said intermediate colour. During mounting of the animal (5), the upper film is abraded, revealing the contrasting intermediate layer and thus signifying the animal is in oestrus.

Figure 3a-3b shows a further alternative embodiment wherein said indicator means (2,3) in the form of a marker (9) is placed on the caudal portion of the animal (5).

The marker (9) incorporates a light coloured backing cloth (10) and a visually distinctive substance in a frangible container (11). The releasable marker (9) is attached by a self-adhesive coating on the underside of the backing cloth (10).

When the animal (5) is mounted, the frangible container (11) breaks or in some way releases the highly visible substance which then spreads over a portion of the backing cloth (10) to give a distinctive contrast between the dark-coloured substance and the surrounding backing cloth (10). The substance may be a dye or ink or any other appropriately visible substance.

Although in prior art systems the predominant means of observing the release of the highly visible substance (indicating that mounting has occurred) is by human observation, the present invention does not rely on same and consequently, said substance may be detectable in part of the electromagnetic spectrum outside normal human vision such as infrared or ultraviolet. Furthermore, said substance may be produced by combining two previously inert substances which, upon mixing (by the crushing action of the mounting animal (5) ), react to form a different coloured substance or output heat or electromagnetic radiation of some form.

Figure 4a-4b shows such a variant of the embodiment shown in figure 3a-b wherein a sensor and indicator means (2,3) in the form of a holder (12) including 2 or more reactive chemicals held separately (as shown in figure 4a) until the animal is mounted causing rupturing of the chemical holders allowing them to mix and react (as shown in figure 4b). In this embodiment, the reaction causes chemicals on the holder (12) to fluoresce, thereby indicating mounting has occurred.

In a further variant, figure 5a-5b shows a sensor and indicator means (2,3) in the form of a further chemical holder (13) which in its undisturbed state (i. e. before mounting has occurred (as shown in figure 5a) ), the holder (13) is at an ambient temperature. After mounting, (as shown in figure 5b), the chemicals are mixed as previously described, causing a thermal reaction thereby generating a hot spot in the area of the holder (13). The increased infrared emissions (14) from the holder (13) may be detected by thermal imaging equipment (15).

Figure 6a-6b shows a further embodiment showing a sensor and an indicating means (2,3) in the form of a fluorescent dye (16) which is applied to the groin area of the mounting animal. Thus, before mounting occurs, the caudal area of the cow (5) is unmarked (as shown in figure 6a) whilst after mounting (as shown in figure 6b) the fluorescent dye is smeared on to the mounting animal (5). The fluorescent dye (12) only becomes discernible after illumination by an external excitation source such as an ultraviolet light lamp (17) causing the fluorescent dye (16) to fluoresce ultraviolet radiation (18).

In further preferred embodiments not shown, the sensor means may detect non- visual manifestations that oestrus has occurred, such as a measurement from a pressure sensor or a pedometer measuring the increased movement of the animal or the like may be combined with a separate indicator means (3) in the form of an LED display, modulated light signal output, or any other convenient mechanical, electromechanical or electronic display forms.

It will be appreciated however that although active electronic or electromechanical displays may be used to provide information such as elapsed time since mounting, frequency of mounting, and/or (optionally) the identity of the mounting animal, such indicator means require a supply of electrical power and as such pose an additional ongoing maintenance and supply issue.

The present invention allows any of the aforementioned means of detecting a manifestation of oestrus to be automatically detected using machine vision in the form of an automated visual detection system (4) comprised of a visual sensor such as the thermal imager (15) shown in figure 5b) or a CCD camera (22) as shown in figure 7 or any other means of acquiring an image related to the appearance of the detector means (3). The automated visual detection system (4) also includes an image processor (not shown) for processing the image from the CCD camera (22) and processing same to determine the oestrus status of the animal. In the embodiments represented in figures 1-6, figures 1a-6a represent the sensor/detector means (2,3) in a first"undisturbed"state before mounting has occurred and figures 1 b-6b indicates the sensor/detector means (2,3) in a second "disturbed"state after mounting has occurred.

The image processor means determines whether the image from the visual sensor (22) indicates a manifestation of oestrus (e. g. mounting) according to whether the image meets at least one predetermined criteria. Each predetermined criteria may be defined according to the particular characteristics of the system and may include a comparison of; a reference image for the undisturbed'first'state with the measured image and/or a reference image for said used'second'state with the measures image to determine whether one or more image parameters exceeds a predetermined threshold value Said image parameters may include, but are not limited to, colour, contrast, shape, configuration, texture/pattern, intensity, wavelength/frequency, or any other measurable property of the input image.

After the image processor has determined the oestrus status of the animal (5) according to the image detected by the visual sensor (22) received from the indicator means (3), the information will be used as part of herd management practices to further reduce manual intervention and improve efficiency.

Figure 7 shows a schematic representation of a further aspect of the present invention wherein the animal (5) enters automated drafting means (18) through an entry race (19) with a first exit race (20) and a second exit race (21).

The animal's (5) movement through the automated drafting means (18) is controlled by a control mechanism (not shown) configured to control passage of the animal (5) through either the first or second exit race (20,21). The automated drafting means (18) is mechanically configured such that only one of said first or second exit race (20,21) may be opened at any time.

According to one embodiment, an animal (5) entering the entry race (19) passes through the field of view of the visual sensor in the form of CCD camera (22) for example. The camera (22) acquires an image of the sensor/indication means (2,3) on the caudal portion of the animal (5) and determines the oestrus status of the animal is determined in accordance with the previously described methods.

If the animal (5) is deemed to be in oestrus by, for example, displaying evidence it has been mounted, first exit race (20) opens allowing the animal into a holding pen for artificial insemination or examination by the farmer/vet. Conversely, if the animal (5) is deemed not to be in oestrus, the second exit race (21) opens and the animal (5) is allowed to return to grazing.

Figure 8 shows a flow chart representation of a simplified implementation of the management of an animal (5) through an automated drafting means (18) as described above. The animal (5) is optionally fitted with an animal identification or ID means (not shown) such as a transponder unit, bar code, ear tag or the like, which provides a means for uniquely identifying the animal (5). The ID means permits one or more identifiable animal attributes to be recorded and to form part of any animal management decision making process. Thus, the prior history of an animal (5) may be taken into account such that animal attributes such as a history of difficult births, or that the animal has not been inseminated before may for example be used to segregate those animals in a separate enclosure for extra attention by a vet before insemination.

In step 23, the animal (5) is identified (if an animal ID system is being utilised) and viewed by the visual sensor (22). It will be appreciated in some embodiments, the animal ID means may be visual (e. g. a barcode) and thus be acquired by the visual sensor (22) and determined by the image processor.

In step 24, the image of the indicator means (3) on the animal is acquired and processed by the image processor resulting in a determination of oestrus in step 25.

If the animal is not deemed to be in oestrus, i. e. the image from the visual senor does not at least one of the predetermined criteria, it is returned (step 26) via the first exit race to grazing or some other activity such as milking or the like. If the animal meets one of the predetermined criteria in step 25, the animal (5) proceeds through the second exit race (step 27) whereupon natural or artificial insemination is performed (step 28). It will be seen that an ID system is not essential as each animal can be individually assessed for oestrus and drafted accordingly without specific knowledge of the animal's ID or related animal attributes.

Figure 9 shows a flow diagram outline of an example image processing process algorithm for use with the embodiment shown in figure 7.

An image is acquired (step 29) of an animal (5) which enters the automated drafting means (15) or is at least within the visual acquisition range of the visual sensor (22).

A region of interest is optionally selected (step 30) to reduce the computational burden on the system. The region may be determined by a variety of methods. If the animal is located in a narrow stock race (e. g. entry race 19) restricted from excessive movement, the region of interest may simply be defined by a specific portion of the visual sensor field of view which is configured to include the indicator means (3) located on the caudal region of the animal (5).

Alternatively, the region of interest may be a defined area surrounding a particular colour or pattern or the like related to the appearance of the indicator means (3).

Image subtraction is then applied to the acquired image (step 31) to remove unwanted background data and/or as a means of determining if the animal indicator means (3) is part of the acquired image. A colour map (e. g. red, green, blue) of the image is then determined (step 32) and then transposed (step 33) to suit characteristics of human vision. A coarse spectral filter is applied (step 34) such as 'nearest neighbour pixel filtering'.

Thus, according to the first invention, the cows may be automatically scanned for the presence of oestrus and thereafter managed (by segregation for insemination) without need for manual input from the farmer or other humans and without the need for ongoing vigilant observation of each animal.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof.