Method and system for characterizing the gender of an egg

Abstract

The invention relates to a method for characterizing the gender of the embryo of an egg (O) from the presence of an organ within the embryo of the egg, said method comprising steps of: Preparation of the egg, consisting of placing the egg (O) in a lying position on a support, the longitudinal axis (X) of the egg being parallel to said support on which it rests, Waiting the egg (O) thus positioned so that the embryo of the egg migrates towards the top of the egg, Mechanical agitation of the egg by rotation of the egg around its longitudinal axis (X), in order to optimize the positioning of said organ as close as possible to the shell, During the mechanical agitation step, emission through the egg, by a light source (E), of a light flux, and acquisition of several images of the egg, Analysis of the images of the egg (O) generated,the presence of said organ being revealed by absorption contrast between the constituent components of the egg (O) containing blood and said organ of the embryo containing melanin. Figure to be published with the abstract: Figure 3,

Description

Title of the invention: Method and system for characterizing the gender of an egg Technical field of the invention

[0001] The present invention relates to the field of avian production and in particular the non-invasive determination of the gender of avian egg embryos during incubation. State of the art

[0002] The search for an early and non-invasive sexing technique for poultry eggs is a subject that has interested the poultry industry for several years.

[0003] Invasive techniques have been proposed in the state of the art, in particular in patent applications WO98 / 14781, DE102007013102, WO2010 / 103111, US2011 / 0144473A1, WO2017 / 174337.

[0004] Non-invasive optical techniques have also been proposed but they mainly concern the detection of egg fertility and not sexing. On this subject, we can notably cite US patent 9,435,732 and US patent 6,029,080.

[0005] In the web-footed sector for the production of foie gras, the mulard duck was specifically selected because it results from a cross between a Peking duck and a Muscovy duck, which carries an albino gene transmitted only to females of the mulard type. This allows them to be sexed, after hatching, by the color of the eye: The males have black eyes because they contain melanin and the albino females have red eyes. This particularity makes it possible to consider in ovo sexing around the 9th day by candling the eggs. By shaking the egg, it is then possible to bring the eye into contact with the shell, which allows it to be distinguished.

[0006] In the state of the art, candling for sexing uses a visible light-emitting diode that illuminates the egg from above, the egg being positioned at 45°, and a camera positioned at 90° to the axis of symmetry of the egg is intended to capture the light diffusion image. This configuration is not ideal because the homogeneity of the lighting in the egg is poor. Indeed, as the light is diffused in all directions, the longer the path of the light in the egg, the greater the absorption of the light. This therefore results in an intensity gradient from top to bottom, which is all the more reinforced as the light must pass through the yolk, which is more absorbent than the white. The eye of the embryo which floats on the surface of the yolk therefore appears at the edge of the dark zone, which hinders its detection.The high absorption of yolk at this stage of incubation comes from the development of the cardiovascular system which contains hemoglobin, presenting a very high absorption capacity in the . wavelength range of light emitting diode illumination between 400 and 620nm.

[0007] Thanks to a combination of candling and agitation around the 9th day, it is possible to observe the eye in males, but this technique suffers from several drawbacks: • Candling with a light-emitting diode and a monochrome camera does not allow for good contrast of the eye in relation to the cardiovascular system, which is a source of prediction errors. • The shaking process is often quite violent, which can be damaging to the embryo and may affect the hatchability rate. • The further incubation progresses, the more the embryo tends to sink into the yolk, which complicates the stirring process. The movement generally used to bring the eye to the surface is an angular movement around the axis of the egg, which complicates its industrial deployment.

[0008] The referenced publication "CORION MATTHIAS et AL: In ovo sexing of eggs from brown breeds with a gender-specific color using visible-near-infrared spectroscopy: effect of incubation day and measurement configuration", POULTRYSCIENCE, col.101, n°5; May 1, 2022 page 101782, XP055962758, Oxford, also describes a technique for sexing chicken eggs by spectroscopic analysis.

[0009] This prior document describes a technique for sexing chickens using eumelanin, which is contained in large quantities in the feathers of females. The solution is based on spectral data analysis. In this approach, we seek to identify the most significant spectral signatures for sex prediction.

[0010] There are few previous solutions capable of reliably determining the sex of an embryo in the egg because various biological compounds are present in the egg (hemoglobin, melanin, proteins, lipids, etc.) and absorb light flux at different wavelengths with different intensities, making diagnosis complicated. Without special conditioning of the egg, it is difficult to detect the eye of the embryo because it is often not visible through the shell.

[0011] Furthermore, in the visible wavelength range, the absorption of light flux by different biological compounds makes the distinction of the eye very complex and difficult to automate.

[0012] There is therefore a need for a reliable method in which all the steps contribute to determining the gender of the embryo in the egg. The method must be simple to implement and sufficiently rapid.

[0013] The method makes it possible in particular to characterize an embryo at the earliest possible stage. In the case of duck eggs, such characterization is carried out before the 10th day from the start of incubation. More generally, the characterization is carried out in the first third of the incubation procedure. Statement of the invention

[0014] This aim is achieved by a method of characterizing the gender of an egg embryo from the presence of an organ within the egg embryo, comprising steps of: - Preparation of the egg, consisting of placing the egg in a lying position on a support, the longitudinal axis of the egg being parallel to the said support on which it rests, - Holding the egg in this position so that the embryo of the egg migrates to the top of the egg, - Mechanical agitation of the egg by rotating the egg around its longitudinal axis, in order to optimize the positioning of said organ as close as possible to the shell, - During the mechanical agitation stage, emission through the egg, by a light source, of a luminous flux, and acquisition of several images of the egg, - Analysis of the generated egg images, the presence of said organ being revealed by absorption contrast between the constituent components of the egg containing blood and said organ of the embryo containing melanin.

[0015] According to one feature, the method comprises a step of filtering the luminous flux in a narrow spectral band.

[0016] According to one feature, the narrow spectral band is between 650nm and 750nm.

[0017] Advantageously, the narrow spectral band is between 675nm and 725nm.

[0018] According to a particular embodiment, the filtering step is implemented on the stream light emitted by the light source, before transmission into the egg.

[0019] According to another particular embodiment, the filtering step is implemented on the light flux emitted by the light source, after transmission through the egg and before the step of acquiring images of the egg.

[0020] According to another feature, the mechanical stirring step consists of implementing a sequence of rotation of the egg around its longitudinal axis, said sequence consisting at least of rotating the egg on itself around its longitudinal axis in one direction over a first non-zero angular range, then in the opposite direction over a second non-zero angular range.

[0021] According to another particularity, the rotation sequence is implemented by playing on four parameters: - The direction of rotation of the egg; - The rotation speed of the egg; - The acceleration imparted during rotation;

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029] - The angular range of rotation of the egg; The invention also relates to a system for characterizing the gender of an egg embryo from the presence of an organ within the egg embryo, used to implement the method as defined above, the system comprising: - An egg preparation station, configured to place the egg in a lying position on a support, the longitudinal axis of the egg being parallel to said support on which it rests, - A system for mechanically stirring the egg by rotating it around its longitudinal axis, in order to optimize the positioning of said organ as close as possible to the shell, - An imaging system comprising a light source capable of emitting a light flux through the egg, and a device for acquiring several images of the egg, the imaging system being operated to provide images of the egg during its mechanical agitation, - Means for analyzing the generated images of the egg, the presence of said organ being revealed by absorption contrast between the constituent components of the egg containing blood and said organ of the embryo containing melanin. According to a particular feature, the system comprises means for filtering the luminous flux emitted by the light source configured to filter said luminous flux in a narrow spectral band. According to another peculiarity, the narrow spectral band is between 650nm and 750nm. Advantageously, the narrow spectral band is between 675nm and 725nm. According to a particular embodiment, the filtering means are arranged to filter the light flux emitted by the light source, before transmission into the egg. According to another particular embodiment, the filtering means are arranged to filter the light flux emitted by the light source, after transmission through the egg and before acquisition of images of the egg by the acquisition device. According to another feature, the mechanical stirring system is controlled to implement a sequence of rotation of the egg around its longitudinal axis, said sequence consisting at least of rotating the egg on itself around its longitudinal axis in one direction over a first non-zero angular range, then in the opposite direction over a second non-zero angular range. According to another particularity, the rotation sequence is implemented by playing on four parameters: - The direction of rotation of the egg; - The rotation speed of the egg; - The acceleration imparted during rotation; - The angular range of rotation of the egg; Brief description of the figures

[0030] Other characteristics and advantages will appear in the detailed description which follows, in conjunction with the appended figures listed below: - [Fig.l] shows schematically the structure of an egg, shown in a horizontal position; - Figures 2A to 2C illustrate the steps of incubation, transfer and preparation of eggs; - [Fig.3] schematically illustrates the operating principle of the imaging system of the invention; - [Fig.4A] shows an example of the emission spectrum of the light source used and illustrates the range of interest P centered around 700nm and [Fig.4B] shows the transmission spectrum of a bandpass filter used to select the range of interest; - [Fig.5] shows an example of the implementation of an installation used to characterize several eggs simultaneously; - [Fig.6] shows a top view of an example of the construction of a mechanical egg stirring system; - [Fig.7] shows several photos captured by the camera of the system of the invention, at different stages of incubation of the egg, and illustrates the interest of the method and the system of the invention;

[0031] Detailed description of at least one embodiment

[0032] In the remainder of the description and as illustrated by [Fig.l], the egg O is defined by its axis of symmetry of revolution (axis (X)) in the longitudinal direction and by its ovoid-shaped surface. Its equator corresponds to the imaginary line drawn on its surface over its entire circumference, at the level of its widest cross-section.

[0033] The system of the invention is used to detect the presence of an organ of a living being in an egg O and ultimately allows, for example, the sex (male or female) of the living being or the state of fertilization to be determined. It is particularly perfectly suited to the sexing of a mulard-type duck egg. But it can also be used to determine the presence, or even the sex, of any other oviparous embryo whose eye, feather or other organ has melanin coloration.

[0034] The method and system of the invention are notably based on analysis by conventional imaging, and not by analysis of spectral data.

[0035] In a known manner, with reference to [Fig.l], the egg O comprises a shell 20, in which is present the embryo 21 to which the eye 22 belongs, and the cardiovascular system 23 containing in particular hemoglobin. The egg also comprises a air chamber or pocket 24 which is generally located on the opposite side of the tip of the egg. In [Fig.l], the egg O is shown horizontally, with the air chamber 24 positioned on the side.

[0036] In order to determine the gender of an embryo in the egg, the method described below comprises the following main steps: - Incubation and transfer; - Preparation of the egg to place it in a specific position and waiting for the egg in this position; - Mechanical agitation of the egg; - During the mechanical agitation stage, imaging of the egg; - Analysis of the generated egg images; Incubation and transfer

[0037] [Fig.2A]

[0038] [Fig.2B]

[0039] It should be noted that the incubation is implemented in a known and conventional manner.

[0040] During incubation ([Fig.2A]), the eggs are placed on incubation grids 11 in an incubator 10 having a controlled atmosphere, in particular in terms of temperature and humidity. Conventionally, the temperature in an incubator is controlled around 37.5°C. During incubation, the eggs are for example placed in a vertical position, that is to say with their longitudinal axis oriented at 90° relative to the grid. During incubation, as illustrated by [Fig.2A], the incubation grids can tilt 45° to one side or the other every hour to prevent the embryo 21 from sticking to the shell 20.

[0041] Following incubation, for a certain period of time, the eggs are transferred from the incubator to a preparation station. In particular, the incubation grids 11 are then positioned in a horizontal position, parallel to the ground during the transfer.

[0042] During transfer ([Fig.2B]), the eggs are held still in a vertical position (90° - as in [Fig.2B]) or slightly inclined (45°). Preparation and holding of the egg

[0043] [Fig.2C]

[0044] This step consists of preparing the egg so that it is in the best conditions for subsequent characterization.

[0045] It is implemented in a preparation station 12, after an incubation period in a hatchery.

[0046] The preparation station 12 is arranged to hold the egg in a lying position, on a support, the longitudinal axis (X) of the egg O being parallel to the support 13 on which it rests. Such a support 13 may be a plate, a mat, a specific housing, or equivalent. Thus, egg O is changed position compared to that used during the transfer. The lying position allows the internal constituents of egg O to migrate to a new position. Indeed, since the internal constituents are not fixed to the shell, any change in the position of the egg causes a displacement of its constituents.

[0047] Each egg O is thus transferred from the 90° (or 45°) position to the horizontal position. Specific means can be used to ensure this transfer of position, without damage.

[0048] Advantageously, the eggs O are kept lying down in a controlled atmosphere, particularly in terms of temperature, in order to avoid the cooling of the eggs and thus improve the detectability of the constituents.

[0049] The egg yolk or vitellus will always float on the albumen given the difference in density. As for the embryo, it will move towards the highest point of the egg yolk. As a result, the embryo always migrates towards the highest point of the shell. Such maintenance in a lying position lasts between 1 minute and 30 minutes.

[0050] The preparation and waiting step ultimately improves the characterization of the type of the embryo in the egg. The visibility of the internal constituents of the egg (which are otherwise known) is in fact maximal when the egg is lying down. - The air chamber 24 is a physical barrier. It is usually located on the wide base of the egg (opposite the tip of the egg on its longitudinal axis). In the lying position, the air chamber 24 remains fixed in its position and the internal elements migrate to an area where the air chamber 24 cannot mask them. - The surface area occupied by the egg constituents is greater in the lying position and the internal constituents of the egg O spread out more, thus increasing their visibility during characterization.

[0051] Next, the eggs O are brought to the imaging system, still in a lying position, and motionless in the lying position. Ideally, the eggs should not rotate during transfer from the preparation station to the imaging system used to characterize the gender of the embryo in the egg. During characterization, the egg is positioned on a support 4 in a lying position in the same state as that at the end of its preparation. Imaging system: Principle

[0052] [Fig.3]

[0053] [Fig.4A]

[0054] [Fig.4B]

[0055] [Fig.3] illustrates the principle of a unitary imaging system for a single egg O, but we will see that this system can be duplicated for a set of several eggs.

[0056] The imaging system, also called a candling system, mainly comprises a light source E and an image sensor C (camera for example).

[0057] The light source E is for example made up of one or more light-emitting diodes, positioned to illuminate the egg O. The light source E is advantageously positioned to illuminate the egg O from below and the image acquisition device C is advantageously placed above, along the same axis, in order to make an acquisition by transmission. In this case, it should be noted that the support 4 of the egg O must be chosen to allow the light signal S emitted by the light source to pass through. It can thus be chosen to be transparent to allow for example at least 90% of the light signal to pass through, with a minimum of diffusion, and / or for example with an opening through which the light signal S is emitted, and / or have at least one part in the form of a grid intended to be crossed by the signal.

[0058] In a non-limiting manner, the light source E is for example chosen to emit with a spectrum such as that represented by the curve in [Fig.4A].

[0059] In this [Fig.4A], the range of interest P around 700nm is identified.

[0060] [Fig.4B] shows an example of a band-pass filter response around the 700nm range of interest, which can be applied to the light source E (light path upstream of the egg O) or in front of the image sensor C (light path downstream of the egg O). Preferably, a band-pass filter or a set of high-pass and low-pass filters will be chosen which define a transmission window of 50nm width between 675nm and 725nm in order to optimize the contrast between the melanin and the oxyhemoglobin contained in the embryo. The wider the spectral window, the more the contrast will decrease, but the greater the flux received by the image sensor C will be. Advantageously, a window width of 100nm between 650nm and 750nm will not be exceeded to maintain an absorption contrast of at least 10 between melanin and oxyhemoglobin.

[0061] Advantageously, the light-emitting diode(s) of the light source E will have a color temperature which allows sufficient emission around 700nm. At the same time, light-emitting diodes which have a high luminous power will be favored to allow good contrast in eggs having between 7 and 10 days of incubation.

[0062] The imaging system, as shown in [Fig.3], also comprises an image sensor C, for example a camera, used to acquire images of the illuminated egg.

[0063] The camera is for example of the monochrome type, so as to be able to clearly identify the contrast between the areas of the egg O where the light is transmitted and the areas of the egg O where the light is absorbed.

[0064] Preferably, the image sensor C is provided with a spectral band filter narrow centered on the 700nm wavelength. As indicated above, this filter eliminates wavelengths for which egg O constituents, notably the cardiovascular system containing oxyhemoglobin, have a strong absorption which impairs the detection of melanin contained in the eyes of male mulard ducks.

[0065] The wavelength at 700nm is that where there is the maximum difference in absorption between melanin and oxyhemoglobin. Filters centered at 700nm and having a low bandwidth (20 to 40nm) will be preferred, like that of [Fig.4B]. Larger bandwidths are possible but at the expense of the eye's detection quality.

[0066] The filter is preferably positioned between the egg O and the image sensor C, which makes it possible to observe only in the band of interest and therefore also to eliminate any parasitic radiation coming from the environment. It could however be positioned elsewhere, for example between the light source and the egg. Advantageously, the image sensor C is placed in the axis of the light source E.

[0067] For example, a combination of two filters may be used, a low-pass filter which passes wavelengths below 720nm and a high-pass filter which passes waves above 670nm.

[0068] The solution of the invention therefore relies in particular on the capacity of the melanin present inside the egg O to absorb visible light to create sufficient contrast on the image captured by the image sensor C.

[0069] With regard to the sexing of a mulard duck egg O, the use of a narrow range of wavelengths around 700nm makes it possible to have a maximum absorption contrast between the melanin contained in the eyes of the male embryos and the other biological constituents of the egg, in particular with the hemoglobin of the cardiovascular system, the latter having a minimum absorption around 700nm. By this process, the cardiovascular system 23 almost disappears from the image obtained at the sensor, allowing an almost systematic identification of the eye of the male embryos and therefore the identification of its sex in the egg.

[0070] It should be noted that it is also possible to use light-emitting diodes emitting on a narrow spectral band, centered around 700 nm, which makes it possible to dispense with the filtering system while retaining the functionality of eliminating undesirable constituents for eye detection. Similarly, it is possible to use halogen lamps as a light source E in combination with a bandpass filter around 700 nm.

[0071] The filtering at 700nm can also be shifted to another wavelength where the absorption coefficients of melanin and oxyhemoglobin differ sufficiently, as is the case for example around 435nm. It is also It is possible to use a combination (linear, mathematical operation, etc.) of several wavelengths whose absorption coefficients of melanin and oxyhemoglobin differ. For example, the ratio between an image taken at 435nm and another taken at 700nm can be used to further increase the contrast in the image between the eye containing melanin and the cardiovascular system containing oxyhemoglobin.

[0072] Complete egg gender characterization system

[0073] [Fig.5]

[0074] With reference to [Fig. 5], a complete installation makes it possible to process several eggs O at the same time. A support tray 40 may have several separate locations, each intended to support a separate egg O to be characterized. A separate light source E may be used per location and therefore per egg O to be characterized. The same image sensor C may be common to several eggs to be characterized, for example for sixteen eggs (4x4) on the installation shown in [Fig. 5]. The processing means UC are then responsible for processing the images that have been captured by each image sensor C of the installation, according to the principles defined above.

[0075] A mechanical stirring system 3 (see below) is associated with the tray, in order to reposition the embryo 21 of each egg O upwards and thus ensure that it is as close as possible to the shell and therefore to the image sensor C when reading the transmitted light flux. Mechanical agitation system

[0076] [Fig.3]

[0077] [Fig.5]

[0078] [Fig.6]

[0079] The mechanical agitation of the egg makes it possible to position the eye 22 of the embryo as close as possible to the shell 20 to make it as visible as possible by the imaging system.

[0080] The mechanical agitation is carried out on the same station as that used for imaging (see below), the imaging system then being active to acquire images while the mechanical agitation of the egg O is in progress.

[0081] In [Fig.3], the mechanical agitation system 3 is shown diagrammatically for a single station and in [Fig.5], this system 3 is shown diagrammatically for a set of several eggs O to be characterized.

[0082] To mechanically agitate the eggs, the system 3 comprises, for example, rollers 300 in the form of diabolos operated by motors, between which the eggs O are positioned. By rotating these rollers 300, the eggs are made to roll on themselves around their longitudinal axis X. Pads may be provided on the rollers 300 to adhere to the surface of each egg O.

[0083] An example of such a roller architecture is shown in [Fig.6].

[0084] The specific agitation method makes it possible to optimize the positioning of the eye 22 of the embryo as close as possible to the shell 20, allowing an improvement in its detection by the imaging system.

[0085] Mechanical agitation can take several forms. It involves playing on four parameters: - The direction of rotation of the egg; - The rotation speed of the egg; - The acceleration imparted during rotation; - The angle of rotation of the egg;

[0086] It should be noted that differences in speed and acceleration produce different results for embryo visibility: - Medium speed and low acceleration keep the embryo close to the shell 20 throughout the movement; - A strong speed and acceleration project the embryo towards the shell and allow it to be seen for a few images; - The more intense movements (dry back and forth) are brief so as not to damage the embryo;

[0087] Pre-agitation may be carried out in order to bring the embryo and its eye close to the internal surface of the shell 20. This pre-agitation may consist of rotating the egg O on itself around its axis through 360°, at low speed (approximately 0.8 revolutions per second) for a few seconds (between 5 seconds and 12 seconds).

[0088] A one-second pause can then be incorporated into the process before proceeding with the actual mechanical stirring.

[0089] The sequences of mechanical agitation of the egg O described below each led to convincing results, with a view to characterizing the gender of the egg O via the imaging system described above. However, these should be considered in a non-limiting manner. It is of course possible to vary the rotation angles and rotation speeds, without significantly altering the results. The camera of the imaging system is placed above the egg O, the egg being positioned flat along its longitudinal axis (X) relative to the axis of the camera. In the description of the sequence, a round trip designates a rotation of the egg O on itself around its longitudinal axis (X), in one direction of rotation (counterclockwise direction chosen for example as the positive direction) over a first angle of rotation, then in the opposite direction (clockwise direction chosen as the negative direction) over a second angle of rotation (not necessarily identical to the first angle of rotation).

[0090] First sequence: - A first round trip at an angle of +67.5° then -135°, then - Three consecutive round trips making movements of -135° and +135°, covering an area extending between +67.5° and -67.5° from the initial position (total angle of 135°), - from +135° to -135°, at medium speed and low acceleration, then - Return to the initial position (at 0°) then turn the egg 180°, then - Again: - A first round trip at an angle of +67.5° then -135°, then - three consecutive round trips over the range from +135° to -135°, at speed average and low acceleration

[0091] Second sequence: - A round trip between the initial position and +135°, at high speed and acceleration, then - A round trip in the opposite direction between the initial position and -135°, at high speed and acceleration, then - A first round trip at an angle of +90° then at an angle of -180°, then - A round trip over a total angle of 180° at medium speed and acceleration weak, then - Return to the initial position, then turn the egg 180°, then - A round trip between the initial position and +135°, at speed and acceleration strong, then - A round trip in the opposite direction between the initial position and -135°, at high speed and acceleration, then - A first round trip at an angle of +90° then -180°, then - A round trip over a total angle of 180° at medium speed and acceleration weak.

[0092] Third sequence: - A first round trip at an angle of +90° then -180°, then - A round trip over a total angle of 180° at medium speed and acceleration weak, then - A round trip between the initial position and +135°, at high speed and acceleration, then - A round trip in the opposite direction between the initial position and -135° at high speed and acceleration, then - Return to the initial position, then turn the egg 180°, then - A first round trip at an angle of +90° then -180°, then - A round trip over a total angle of 180° at medium speed and acceleration weak, then - A round trip between the initial position and +135°, at speed and acceleration strong, then - A round trip in the opposite direction between the initial position and -135°, at high speed and acceleration.

[0093] During the egg shaking process, the imaging system's camera records videos of the eggs using the candling principle described above. These image banks will be used to classify the embryo's gender. Image processing

[0094] The processing of the images acquired by the image sensor C is carried out by UC processing means.

[0095] In a non-limiting manner, the processing can be carried out by training a first neural network on a base of video sequences, themselves broken down into video sub-sequences of a few images (in practice from 1 to 6 images), these video sub-sequences being labeled in a semi-supervised manner by an image processing algorithm which selects the images having the highest probability of presenting a visible eye (the implementation of such an algorithm is facilitated by the efficiency of the system in revealing the presence of the eye in the image). This neural network can also be used as a semi-supervised labeling tool for learning a new model. For this purpose, a new training database is thus constructed by taking all the sequences of 1 to 6 images for the females and only the sequences of 1 to 6 images selected by the first neural network for the males.This ensures that only video sequences with a very high probability of eye presence for males are included in this new learning base. With this second iteration, the prediction performance reaches 99% for males and 97% for females. This semi-supervised approach for creating new databases and learning new models can be repeated as many times as necessary to achieve the desired prediction performance for the model.

[0096] Other processing solutions could of course be implemented.

[0097] [Fig.7] shows several photos taken by the image sensor C at different stages of incubation of an egg (at D7, D8, D9, D10), in the case of the first configuration described above. The dark area represents the biological component containing the melanin absorbing the signal emitted on the wavelength range centered on 700nm. In the case of a male mulard duck, this is its eye (black spot on the images shown). We can see that this eye always remains perfectly detectable, from the 7th day of incubation until the 10th day.

[0098] Thus, by choosing to filter the wavelengths around 700nm, we obtain a very significant contrast between melanin and hemoglobin (ratio of 50 in the absorption coefficients), which makes the eye stand out perfectly.

[0099] The solution of the invention thus presents numerous advantages: - It allows an egg to be characterized in a reliable, non-invasive manner, at an early stage of incubation; - It uses simple and reliable means; - It is adaptable to existing installations;

Claims

Claims

1. Method for characterizing the gender of the embryo of an egg (0) from the presence of an organ within the embryo of the egg, said method being characterized in that it comprises steps of: - Preparation of the egg, consisting of placing the egg (0) in a lying position on a support, the longitudinal axis (X) of the egg being parallel to said support on which it rests, - Waiting the egg (0) thus positioned so that the embryo of the egg migrates towards the top of the egg, - Mechanical agitation of the egg by rotation of the egg around its longitudinal axis (X), in order to optimize the positioning of said organ as close as possible to the shell, - During the mechanical agitation step, emission through the egg, by a light source (E), of a light flux, and acquisition of several images of the egg, - Analysis of the images of the egg (0) generated,the presence of said organ being revealed by absorption contrast between the constituent components of the egg (0) containing blood and said organ of the embryo containing melanin.,

2. Method according to claim 1, characterized in that it comprises a step of filtering the luminous flux in a narrow spectral band.

3. Method according to claim 2, characterized in that the narrow spectral band is between 650nm and 750nm.

4. Method according to claim 2, characterized in that the narrow spectral band is between 675nm and 725nm.

5. Method according to one of claims 2 to 4, characterized in that the filtering step is implemented on the light flux emitted by the light source (E), before transmission into the egg.

6. Method according to one of claims 2 to 4, characterized in that the filtering step is implemented on the light flux emitted by the light source (E), after transmission through the egg (0) and before the step of acquiring images of the egg.

7. Method according to one of claims 1 to 6, characterized in that the mechanical stirring step consists of implementing a sequence of rotation of the egg around its longitudinal axis, said sequence consisting at least of rotating the egg (0) on itself around its longitudinal axis (X) in one direction over a first non-zero angular range, then in the opposite direction over a second non-zero angular range.

8. Method according to claim 7, characterized in that the rotation sequence is implemented by playing on four parameters: - The direction of rotation of the egg; - The speed of rotation of the egg; - The acceleration imparted during rotation; - The angular range of rotation of the egg;

9. System for characterizing the gender of the embryo of an egg (0) from the presence of an organ within the embryo of the egg, used to implement the method as defined in one of claims 1 to 8, characterized in that it comprises: - A preparation station (12) of the egg, configured to place the egg in a lying position on a support, the longitudinal axis (X) of the egg being parallel to said support on which it rests, - A system (3) for mechanically stirring the egg by rotating the egg around its longitudinal axis (X), in order to optimize the positioning of said organ as close as possible to the shell, - An imaging system comprising a light source (E) capable of emitting a light flux through the egg (0), and a device for acquiring several images of the egg, the imaging system being actuated to provide images of the egg during its mechanical stirring,- Means for analyzing the generated images of the egg (0), the presence of said organ being revealed by absorption contrast between the constituent components of the egg (0) containing blood and said organ of the embryo containing melanin.,

10. System according to claim 9, characterized in that it comprises means for filtering the luminous flux emitted by the light source (E) configured to filter said luminous flux in a narrow spectral band.

11. System according to claim 10, characterized in that the band narrow spectral range is between 650nm and 750nm.

12. System according to claim 10 or 11, characterized in that the narrow spectral band is between 675nm and 725nm.

13. System according to one of claims 10 to 12, characterized in that the filtering means are arranged to filter the light flux emitted by the light source (E), before transmission into the egg.

14. System according to one of claims 10 to 12, characterized in that the filtering means are arranged to filter the light flux emitted by the light source (E), after transmission through the egg (0) and before acquisition of images of the egg by the acquisition device.

15. System according to one of claims 9 to 14, characterized in that the mechanical stirring system is controlled to implement a sequence of rotation of the egg around its longitudinal axis, said sequence consisting at least of rotating the egg (0) on itself around its longitudinal axis (X) in one direction over a first non-zero angular range, then in the opposite direction over a second non-zero angular range.

16. System according to claim 15, characterized in that the rotation sequence is implemented by playing on four parameters: - The direction of rotation of the egg; - The speed of rotation of the egg; - The acceleration imparted during rotation; - The angular range of rotation of the egg;