WO1996004551A1

WO1996004551A1 - Animal fat assessment

Info

Publication number: WO1996004551A1
Application number: PCT/AU1995/000471
Authority: WO
Inventors: Alexander Forrest; Anthony John Gordon
Original assignee: Meat Research Corporation
Priority date: 1994-08-04
Filing date: 1995-08-04
Publication date: 1996-02-15
Also published as: AUPM727194A0

Abstract

The assessment of the fat content of an animal by a surface profile capture means (11, 20) which includes a line of retractable locator probes (12) or other locator means to provide data of the profile of the animal which can be analysed by an analysing means (31) to derive a parameter of the profile of the animal, such as the length of the profile between two known spaced planes, which is indicative of a degree of fatness or leanness of the animal.

Description

ANIMAL FAT ASSESSMENT TECHNICAL FIELD

This invention relates to the assessment of the fat content of an animal, particularly a live animal although the invention relates also to animal carcasses. The fatness or thinness of an animal is related to its value. This is related to its yield of saleable meat. For a farmer it is thus important to predict yield on the live animal

on the farm. The animal may be graded for example on the farm prior to sale for slaughter or for selection for breeding or at sale yards or abattoirs prior to slaughter according to a scale of expected fat content of the carcass after the animal is slaughtered.

BACKGROUND ART

The assessment of fat content of the live animal is presently carried out manually by subjective assessment. Such subjective assessment is often carried out in a non-formal and often haphazard way. However the assessment is usually done very quickly. For

example sheep can be drafted for fatness by eye at the rate of up to around 20 per minute. Sometimes assessment includes feeling certain sections of the animal, particularly sections

of the spine so as to enable a preliminary assessment of the likely level of fat in the carcass as a result of feeling the subcutaneous fat on either side of the spine.

Introduction of objective systems are usually resisted by producers and livestock agents because the extra benefits due to improved accuracy of assessment are offsefby the extra costs of the operation.

Ultrasonic devices have been developed for pigs and cattle to introduce

objectivity. They measure the subcutaneous fat thickness and in more recent times marbling level within some muscles. They are often expensive and invariably much slower (by as much as 100 fold) to use than the traditional visual assessment. The value of an increase in accuracy at the cost of slower throughput is often questioned by farmers. With sheep, ultrasound can only be used by clipping the wool from the surface which rules the process out from an operational viewpoint. DISCLOSURE OF INVENTION It is an object of the present invention to provide an apparatus and method for providing an automatically determined measure indicative of the expected fat content of

an animal or animal carcass.

The apparatus according to the invention is for assessing and providing a measure of the expected fat content of an animal and comprises surface profile capture means for operative association with the animal and operative to generate signals indicative of the

profile of a predetermined portion of the animal and analysing means for analysing the signals so as to derive a parameter of the profile which is indicative of a degree of fatness or leanness of the animal.

The invention is based on the principle of capturing a profile and analysis so as to measure the boniness of the animal, i.e. the degree of undulation of the surface of the skin or hide at the predetermined region caused by bones protruding under the skin, fat and muscle. The parameter of the profile may be, for example, the length of the line along the surface between two points which is expected to be shorter with a fat animal where the subcutaneous fat softens or rounds the shape compared to a lean bony animal where bony protrusions and/or emaciation cavities between the two points lead to a longer length of line. Similarly, surface area between three or more non-colinear points which are at fixed known distances apart on a flat plane will be greater when placed on an undulating plane such as the surface of a lean animal. A further possible parameter comprises the area or volume defined between the surface and an imaginary line or plane extending through the animal between surface points which are fixed known distances apart. Other parameters may be derivatives of such measures, including ratios, differential derivatives, etc.

The invention provides an apparatus wherein the surface profile capture means may include a sound source operatively associated with the animal so as to generate sound signals which are reflected from a surface of the animal, and a sound detector for detecting the reflected sound signals and for generating said data signals in response to detection of the reflected sound signals; the analysing means receiving said data signals associated with the reflected sound signals and deriving from the data signals said parameter of the profile.

Preferably said surface profile capture means comprises a mechanical surface profile capture means including surface position locator means for contacting the surface of the animal body at a desired portion of the body, the locator means upon contact with the surface adopting positions depending on the surface profile at the portion of the body;

and sensing means for sensing the position adopted by the locator means and for generating indications of those positions which constitute said data signals, the analysing

means being operative to analyse the signals from the sensing means so as to derive the parameter of the profile which is indicative of a degree of fatness or leanness of the animal body. An advantage of the mechanical apparatus is that it can be used on woolly sheep to penetrate to the skin surface. Wool interferes with acoustic based technologies because of difficulty penetrating the wool.

The surface position locator means can comprise a plurality of locator members

which in use are brought into contact with the surface of the animal so that each contacts the surface at a respective single contact point, the contact points being spaced along a

length of the animal's body. In one preferred form of an apparatus according to the invention the locator members may comprise locator probes, each of which is movable independently of the other locator probes between a retracted position and an advanced position so that in use contact with the animal's body at a point along said length determines the position of the locator member between its two extreme limits. The locator members can be mounted for hinging or pivoting movement from their retracted positions towards and into contact with the animal body. The locator members also may be movable linearly generally along their

lengths between their advanced and retracted positions.

Preferably the locator members are arranged in a line and in use are able to be

initially all located in their advanced positions so that when they are all brought into contact with the surface of the animal's body, a number are moved towards their retracted positions. The contact points are arranged in a general line so as to define a profile line in a plane through the animal body, the line being defined by the plane of movement of the locator members upon contact with the animal body. The plurality of locator members in one preferred form are linearly movable probes arranged in a straight line and which in use extend in a line at right angles to the medial plane of the animal body. The locator members for example may be arranged to be brought into contact with the spinal region of the animal body, with the line of locator members being transverse to the general line of the animal spine. The locator members may contact the animal body in the vicinity of the spine and preferably across and on both sides of the spine.

The sensing means for sensing the positions adopted by the locator means may

comprise transducers for sensing the positions adopted by each of the locator members. Preferably the sensing means comprises slide potentiometers, each potentiometer being operatively coupled to a respective one of the locator members so that the axial movement of the locator member when brought into contact with the surface of the animal body is transferred to the slide of the potentiometer so that the linear position of the potentiometer slide correlates to the axial position of the respective locator member, the analysing means receiving electrical signals related to the resistance of the respective potentiometers and analysing an electrical parameter which is directly indicative of the resistance of the each of the potentiometers and subsequently processing said electrical signals to derive the parameter of the profile of the animal.

The resistance of each potentiometer therefore can directly influence an electrical signal whose magnitude, frequency, phase or other electrical parameter is directly indicative of the resistance of the potentiometer. Such signals for example may be passed

to an analogue to digital or A/D converter for subsequent digital processing.

The analysing means operative to analyse the signals from the sensing means to

derive a parameter of the profile may be any suitable analysing means, such as a suitably programmed microprocessor or the like. For example, the sensing signals as mentioned above may be passed through an A/D converter for digital processing by the analysing means.

In one alternative form of the invention the surface position locator means comprises a single locator means which is moved along a desired length of the surface of the animal's body while maintaining contact therewith, the locator means having the sensing means associated therewith so that as the locator means is moved along the profile of the length of the surface of the animal's body, signals indicative of the positions adopted by the locator means are generated.

In an apparatus according to the invention the parameter of the profile, which is

derived to be indicative of the profile, comprises a measure related to the length of a line along the surface of the animal between two points spaced on opposite sides of the spine of the animal. The parameter of the profile may comprise a measure related to the area defined between a first straight line and a second convex line, the first straight line being between two points on the surface of the animal located on opposite sides of the spine of the animal and the second convex line being between the same two points on the surface of the animal and crossing the spine. The two points spaced on opposite sides of the spine

of the animal are preferably equidistant from the medial plane of the animal and the straight line between said two points is orthogonal to the medial plane.

The parameter of the profile may be for example the length of the line which joins the successive points of contact of the locator members with the surface of the animal

body. For example, it is believed that, particularly in the case of cattle, fat cattle have a relatively flat profile along a line transverse to the medial plane of the animal containing

the spine and across the spine itself Such a surface line across the spine of a fat animal between two points of fixed absolute spacing therefore can have a minimum length. On the other hand, a very lean, including an undernourished cow, can have a very prominent spine projecting sharply upwardly throughout the length of the animal body so that measurement of a surface line length taken across such a spine will reveal a profile transverse to the spine having a sharp rise to the tops of the featherbones along the spine, the profile then dropping down the other side of the featherbones before flattening out as it extends outwardly away from the spine. Such a profile has a greater length than the length of the line for the fat animal carcass.

According to the invention there is also provided a method for assessing and providing a measure of the expected fat content of an animal, the method comprising the use of the apparatus according to the invention. Possible and preferred features of the present invention will now be described with particular reference to the accompanying drawings. However it is to be understood that the features illustrated in and described with reference to the drawings are not to be construed as limiting on the scope of the invention. In the drawings: BRIEF DESCRIPTION OF DRAWINGS

Fig. 1 shows schematically a fat assessment apparatus embodying the present invention,

Fig. 2 shows an exploded perspective view of the apparatus of Fig. 1,

Fig. 3 shows a typical profile across the back of a cow traversing the spine

measured by the apparatus of the present invention, and

Fig. 4 shows possible measurement sites on an animal. MODE FOR CARRYING OUT THE INVENTION

The apparatus illustrated includes surface position locator means 11 comprising a

plurality of locator probes 12 movable linearly within a housing 13 except for one or both of the end probes 12a, 12b which may be fixed so as to contact the animal and enable repeatable placement of the locator means so that the movable probes move consistently independent of the user. Initially the probes 12 can all be in extended positions, e.g. under the influence of respective springs 15 which bias the probes into their outermost positions. The probes 12 are arranged in a line. The apparatus is brought into contact with the animal surface 16 transverse to the line of the spine and across the spine so as to adopt for example the positions shown in Fig. 1 or 2. Generally the surface position locator means 11 will comprise fifteen probes for measurement of the fat content of cattle. However nine probes can be adequate for measurement of sheep, although fifteen probes may still be used with the probes positioned closer together than for use on cattle. As shown in Fig 4, the readings can be taken at numerous parts of the body of the animal along the spine It is believed that the most reliable in terms of repeatability and true "fatness" indications are achieved from the positions from the mid back (sites 5 to 7 in Fig 4) or just above the tail (site 9) Tests at these sites have shown least variation in the readings for a single animal when repeated readings were taken by the same operator and by different operators Readings taken towards the cranial end of the spine (sites I to 4), proved more difficult to obtain, particularly due to greater animal movement, although

on a closely confined animal or on the carcass of a slaughtered animal, these positions may prove suitable

Associated with each of the locator probes 12 is a position sensing means 20. In

Fig 2, the sensing means 20 comprises a respective sensor 21 for each of the probes, the sensors 21 for example comprising slide potentiometers 22 having projections 23 which engage respective heads 17 of the locator probes 12 so as to follow movements of the probes The positions adopted by the slide potentiometers can be translated by any electrical means to signals indicative of the respective positions of the probes For example, analogue signals indicative of the resistance of each potentiometer 22 can be passed to an analogue to digital converter 30 so that digital output signals indicative of the positions of the respective locator probes 12 can be generated for further processing. In order to initiate the measurement of the particular respective positions of the probes the centre probe 12c is intended to be centralised on the animal spine When the centre probe is retracted to a predetermined extent, a microswitch (not shown) can be closed to initiate

"reading" of the position of the potentiometer projections 23 to thereby read the position of the probes If desired, the centre probe 12c can have a microswitch only and no potentiometer so that its retraction to a predetermined extent could initiate readings from potentiometers associated with the other probes 12.

Analysing means 31 is provided to analyse the signals and derive a parameter of the profile indicative of a degree of fatness or leanness of the animal expected for that particular sensed profile. For example, the analysing means 31 may comprise a

programmed microprocessor or the like. The parameter can be fed to an output device such as a printer, display (such as an LCD display) or memory 32 for operator use. The A/D converter 30, analysing means 31 and output device 32 may all be incorporated in the housing 13, along with power supplies, interface connectors, etc.

The parameter of the profile may comprise the lineal length of the profile defined by the contact points of the locator probes and this length can be simply calculated from the signals indicative of the positions of the potentiometer slides 23. For example, a

substantially flat or very shallow curved profile across the spine can indicate a fat animal and in this case the length of the line defined by the points of contact of the locator probes can be minimal. On the other hand, a very lean emaciated animal will have a prominently projecting spine so that the profile can have a shaφ peak leading to a maximised length of the line joining the points of contact of the locator probes.

An alternative apparatus of the invention may include only two end probes 12a and 12b and an extendable flexible line extending between the bottom points of the probes 12a and 12b. In use the flexible line may be fixed at the bottom point of the probe 12a and extend around a pulley at the bottom of the probe 12b and then extend to wind onto a reel. The reel has an associated rotary potentiometer so that as the line is pulled out from the reel the sliding contact moves around the potentiometer. Thereby in use the two probes are positioned on either side of the spine of the animal with the flexible line being pulled out of the reel until the ends of both the probes 12a and 12b contact the animal's surface. The line will then extend along the profile of the animal between the two points. The length of line extending between the two points provides a parameter of the profile of the animal. For example, the shorter the length then the flatter the back of the animal and the higher the "fatness" of the animal.

An additional or alternative parameter that can be determined by the apparatus of

the invention and is indicative of the degree of fatness can be the area A under the profile if plotted as shown in Fig. 3. This area A can be quantified by the sum of the lengths travelled by the probes 12.

Tests on a prototype of the mechanical apparatus described and illustrated have demonstrated a relationship between the "fatness" and the profile meter reading. The "fattest" animals had more flatter regions than the thinner animals. Site 9 (just over the tail) may show the most promise for discrimination of fat and thin animals. The readings vary from site to site along the back, as expected, due to the variations in "flatness" of the profile. The least undulating part of the animals back was at site 7 which corresponds to the "aitch bone" region. The fatter animals have "flatter" or less undulating profiles with reduced readings on the scale used. A known grading of "fatness" of animals is on a scale of 1 to 5. Since this is a "coarse" grading the parameter derived from the mechanical

apparatus can be allocated to one of five continuous but mutually exclusive ranges to derive a grading of the animal "fatness" on the same 1 to 5 scale. The analysing means 31 may include an analysis of the parameter measured so as to provide an output in the 1 to 5 range. Further the analysing means 31 may include a read only memory having different ranges for different breeds and/or ages of animals so that the same instrument can be used to measure the "fatness" of calves or sheep or bulls or various breeds thereof It may also be possible to have a more precise or "fine" scale if this is required in certain instances or for certain statistical analysis. Animals or carcasses can be classified for different processing operations according to the derived fatness parameter.

The apparatus described in relation to the drawings can enable the automated measurement of a profile along a length of an animal body and derivation of a measure of the degree of fatness. It has been found that at any given site there were no differences in

the average readings taken by two different operators. The reproducibility appeared to be at least equal and probably better than that obtained by some ultrasonic devices. The speed of operation was many times faster however. The apparatus enables readings to be quickly, reproduceably and repeatably derived by relatively unskilled persons. The readings can be substantially independent of the operator of the apparatus. Potentially the reading could be automated by locating and operating the apparatus upon animals being

successively fed through a race.

Although the particular illustrated apparatus comprises a single line of locator probes, the apparatus may include multiple parallel lines of locator probes 12 so as to provide three dimensional profile data, e.g. profile data along a length of the animal

surface, i.e. longitudinally relative to the line of the spine as well as transverse to the spine and vertically. Such three dimensional data can enable for example detection of the general line of the spine and adjustment in the analysis of the sensed probe positions for possible inaccurate positioning of the apparatus, e.g. compensation for skew positioning of the apparatus where the line of locator probes is not substantially at right angles to the longitudinal line of the spine. Such three dimensional data can also enable detection of and compensation for local surface irregularities which could produce inaccuracies in the analysis of a simple two dimensional apparatus. Furthermore, three dimensional data can enable additional parameters indicative of the degree of fatness to be derived.

It will be appreciated that variations to the particular apparatus described and illustrated can be incoφorated without departing from the scope of the invention. For example the number and spacing of the locator probes can be varied as desired, e.g. between 3 and 40, the numbers of rows of probes can be varied, e.g. from 1 to 4. The

sensing means although illustrated as slide potentiometers, could be other linear displacement measuring means and may include other types of transducers such as optical,

acoustic or other radiation transducers. If necessary the sensing means may include

separate emission and detection means, whereby a light beam, optical wave or radiation is bounced off one or more points on the back of an animal and one or more detectors detect the reflection and determine the profile of the animal. The emission may be a linear light, optical wave or radiation so that the linear profile of the animal is assessed in one action.

Claims

1. An apparatus for assessing and providing a measure of the expected fat content of an animal, comprising surface profile capture means (1 1, 20) for operative association with the animal and operative to generate data signals indicative of the profile of a predetermined portion of the animal; and analysing means (31 ) for analysing the data signals so as to derive a parameter of the profile which is indicative of a degree of fatness

or leanness of the animal.

2. An apparatus according to claim 1 wherein said surface profile capture means comprises a mechanical surface profile capture means (1 1, 20) including surface position locator means (1 1) for contacting the surface of the animal body at a desired portion of the body, the locator means (11) upon contact with the surface adopting positions

depending on the surface profile at the portion of the body; and sensing means (20) for

sensing the position adopted by the locator means (11) and for generating indications of those positions which constitute said data signals, the analysing means (31) being operative to analyse the signals from the sensing means (20) so as to derive the parameter

of the profile which is indicative of a degree of fatness or leanness of the animal body.

3. An apparatus according to claim 2 wherein the surface position locator means (11) comprises a plurality of locator members (12) which in use are brought into contact with the surface of the animal so that each contacts the surface at a respective single contact point, the contact points being spaced along a length of the animal's body.

4. An apparatus according to claim 3 wherein the locator members (12) comprise

locator probes (12), each of which is movable independently of the other locator probes (12) between a retracted position and an advanced position so that in use contact with the

animal's body at a point along said length determines the position of the locator member between its two extreme limits.

5. An apparatus according to claim 4 wherein the locator members (12) are mounted for hinging or pivoting movement from their retracted positions towards and into contact with the animal body.

6. An apparatus according to claim 4 wherein the locator members (12) are movable linearly generally along their lengths between their advanced and retracted positions.

7. An apparatus according to claim 6 wherein the locator members (12) are arranged in a line and in use are able to be initially all located in their advanced positions so that

when they are all brought into contact with the surface of the animal's body, a number are

moved towards their retracted positions.

8. An apparatus according to any one of claims 4 to 7 wherein the sensing means (20) for sensing the positions adopted by the locator means (12) comprises transducers (22) for sensing the positions adopted by each of the locator members (12).

9. An apparatus according claim 7 to wherein the sensing means (20) for sensing the position adopted by the locator means comprises slide potentiometers (22), each potentiometer being operatively coupled to a respective one of the locator members (12) so that the axial movement of the locator member (12) when brought into contact with the surface of the animal body is transferred to the slide of the potentiometer (22) so that the linear position of the potentiometer slide (23) correlates to the axial position of the respective locator member (12), the analysing means (31) receiving electrical signals related to the resistance of the respective potentiometers and analysing an electrical parameter which is directly indicative of the resistance of the each of the potentiometers and subsequently processing said electrical signals to derive the parameter of the profile of the animal.

10. An apparatus according to claim 2 wherein the surface position locator means (1 1) comprises a single locator means (11) which is moved along a desired length of the surface of the animal's body while maintaining contact therewith, the locator means (1 1) having the sensing means (20) associated therewith so that as the locator means (1 1) is moved along the profile of the length of the surface of the animal's body, signals indicative of the positions adopted by the locator means are generated.

11. An apparatus according to claim 1 wherein the surface profile capture means includes a sound source operatively associated with the animal so as to generate sound signals which are reflected from a surface of the animal , and a sound detector for detecting the reflected sound signals and for generating said data signals in response to

detection of the reflected sound signals; the analysing means receiving said data signals associated with the reflected sound signals and deriving from the data signals said parameter of the profile.

12. An apparatus according to any one of the preceding claims wherein the parameter

of the profile comprises a measure related to the length of a line along the surface of the animal between two points spaced on opposite sides of the spine of the animal.

13. An apparatus according to any one of the preceding claims wherein the parameter of the profile comprises a measure related to the area defined between a first straight line and a second convex line, the first straight line being between two points on the surface of the animal located on opposite sides of the spine of the animal and the second convex line being between the same two points on the surface of the animal and crossing the spine.

14. An apparatus according to claim 12 or 13 wherein the two points spaced on opposite sides of the spine of the animal are equidistant from the medial plane of the animal and the straight line between said two points is orthogonal to the medial plane.