Abstract:
An artificial insemination device for artificially inseminating sows in particular includes a saddle which is placed on the back of a female. A support on the saddle supports a sachet containing animal semen and holds the sachet in a globally vertical position. A constant pressure applicator associated with the sachet maintains the animal semen contained in the sachet at a constant pressure

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to artificial insemination devices, more particularly suitable for breeding sows, of the kind including a saddle adapted to be placed on the back of a female and provided with support means for a sachet containing animal semen.  
           [0003]    2. Description of the Prior Art  
           [0004]    An artificial insemination device of the kind mentioned above and suitable for so-called “gravity” artificial insemination, which does not require the continuous presence of the operator throughout the period of insemination, is known in the art; the sachet of semen is attached to the saddle and connected to an insemination probe inserted in the neck of the uterus of the female to be inseminated.  
           [0005]    A known advantage of this kind of device is that it facilitates detecting when the animal is on heat. If the female is not yet ovulating, it generally attempts to get rid of the saddle by lying down or shaking itself; it is therefore sufficient to place this kind of device on the female and observe its behavior; if it tolerates the saddle, then the sachet of animal semen is installed and insemination is allowed to proceed by natural flow of the semen due to the effect of gravity and uterine contractions that aspirate the semen; while this is happening the operator can carry out other inseminations.  
           [0006]    This kind of device is described in the document FR-A-2 720 929 and in French patent application 99 11433 filed Sep. 13, 1999, for example.  
           [0007]    It is often recommended to apply to the sachet containing the semen a pressure slightly greater than that resulting from gravity alone, in particular when inseminating young nulliparous sows; however, to prevent backflow and the attendant risks of loss of fertility or prolificity, the pressure must not be too high.  
           [0008]    The document FR-A-2 720 929 cited above also proposes to associate with the sachet containing the semen an empty sachet connected to an inflation member consisting of a stethoscope bulb, for example.  
           [0009]    This has drawbacks; on the one hand, it is not easy to adjust the pressure; on the other hand, the pressure falls as the semen flows into the uterus of the animal.  
           [0010]    An object of the present invention is to avoid these drawbacks.  
         SUMMARY OF THE INVENTION  
         [0011]    The invention provides an artificial insemination device for artificially inseminating sows in particular, the artificial insemination device including a saddle adapted to be placed on the back of a female, a support on the saddle adapted to support a sachet containing animal semen and to hold the sachet in a globally vertical position, and a constant pressure applicator adapted to be associated with the sachet to maintain the animal semen contained in the sachet at a constant pressure.  
           [0012]    The constant pressure is advantageously adjustable.  
           [0013]    The sachet is preferably made from a flexible material, advantageously from a transparent flexible material, and the constant pressure applicator consists of a weighted clamp adapted to seal the sachet hermetically, to form an air bubble above the level of the animal semen contained in the sachet, and to slide along the sachet under its own weight as the level of the animal semen falls in the sachet as insemination proceeds as the result of uterine contractions of the animal.  
           [0014]    In a preferred embodiment the clamp includes two rollers adapted to rotate about two parallel axles extending over at least the whole of the width of the sachet and to press two walls of the sachet together in a sealed manner.  
           [0015]    The constant pressure is advantageously adjusted by calibrating the rollers.  
           [0016]    The support on the saddle preferably includes an arm adapted to have the sachet suspended from its end; the arm preferably carries two hooks adapted to be passed through at least one pair of holes in the sachet; the hooks are preferably fixed to the end of the arm; the hooks can instead be mounted on the arm so that they can slide along the arm.  
           [0017]    The hooks are advantageously carried by an elastic clip fitted tightly around the arm so that its position along the arm is adjustable.  
           [0018]    The saddle is advantageously rigid.  
           [0019]    The saddle advantageously has a base adapted to rest on the back of the female; the base is a plate or a stainless wire.  
           [0020]    The base carries, in addition to the arm, a globally U-shaped transverse clip whose sides are bent and adapted to grip elastically the flanks of the female; the clip is made from bent wire; the wire comprises two strands at least parts of which are globally parallel.  
           [0021]    The sides of the clip advantageously comprise practically straight sections connected at a sharp angle with no radiusing.  
           [0022]    The base is preferably fixed.  
           [0023]    The base is advantageously formed by extending and deforming the wire constituting the clip.  
           [0024]    Alternatively, the base is rotatably mounted on the saddle; the base is in the form of a wire loop articulated to the clip.  
           [0025]    The arm is advantageously articulated to the saddle; the arm is adapted to occupy at least two positions, one of which is a storage position; the arm is adapted to occupy at least two different insemination positions. 
       
    
    
       [0026]    The invention will be better understood and other advantages will become more clearly apparent in the light of the following description of an artificial insemination device in accordance with the principle of the invention, which description is given by way of example only and with reference to the accompanying drawings.  
       BRIEF DESCRIPTION OF THE DRAWINGS  
       [0027]    [0027]FIG. 1 is a general perspective view showing a sow being inseminated by means of a device in accordance with the invention.  
         [0028]    [0028]FIG. 2 repeats part of FIG. 1 to a larger scale.  
         [0029]    [0029]FIGS. 3 and 4 are perspective views showing a variant of the device with the arm in two different positions.  
         [0030]    [0030]FIGS. 5 and 6 show parts of the device shown in FIGS. 3 and 4, respectively, to a larger scale.  
         [0031]    [0031]FIG. 7 is a perspective view of a variant of the device.  
         [0032]    [0032]FIG. 8 is a plan view of the device shown in FIG. 7 in a storage configuration. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0033]    [0033]FIGS. 1 and 2 show a sow  11  being artificially inseminated using a device  10 .  
         [0034]    The device  10  includes a rigid saddle  12  placed on the back of the female  11 .  
         [0035]    The saddle  12  has a base  13  resting directly on the back of the female  11 .  
         [0036]    An arm  14  is inclined toward the rear, for example at 450°, when the device is in place; its free end is shaped like a rake with two tines, each in the form of a respective hook  15 ,  16 ; the arm  14  is made of stainless wire, rigid and approximately 5 mm in diameter. It is advantageously articulated by means of a small plate  43  at its end to a bracket  27  on the saddle  12  and to which the base  13  and a clip  17  are fastened directly; this articulation means that the arm can be folded, which facilitates storage of the insemination device  10 ; the bracket  27  has two flanges with the small plate  43  of the arm  14  between them; the arm  14  can occupy several positions, as described below with reference to FIGS.  3  to  6 .  
         [0037]    The clip  17  of the saddle  12  is globally U-shaped with the sides slightly bent so that it can firmly encompass both flanks of the female  11 .  
         [0038]    To be more precise, the clip  17  is bent to shape from wire, for example 5 mm diameter stainless wire; the sides  18 ,  19  of the U-shape are doubled back on themselves so that the wire has two globally parallel strands  28 ,  29  spaced apart by a distance of a few tens of millimeters, for example.  
         [0039]    The sides  18 ,  19  are slightly bent inward and imitate as far as possible the front hooves of a boar, and therefore its embrace, which makes it possible to verify if the female is receptive to insemination, stimulates the female and causes discharge of ocytocin, which results in uterine contractions; this kind of clip  17  envelops the belly of the female securely, without it being necessary to strap it on, and ensures that the device is stable.  
         [0040]    Obviously, the rigid saddle  12  can be washed and sterilized.  
         [0041]    The sachet  20  is a flexible sachet of transparent plastics material formed of two films constituting the walls of the sachet and welded together; its transparency enables visual control of artificial insemination; the weld defines a peripheral edge; at one end at least of the peripheral edge there are two lateral holes  21 ,  22  forming eyelets on respective opposite sides of the sachet; the sachet  20  is of the type described in U.S. Pat. No. 5,971,971, for example.  
         [0042]    The distance between the hooks  15 ,  16  on the arm  14  is substantially equal to the distance between the centers of the holes  21 ,  22  so that the sachet  20  can be suspended from the arm  14  by these holes, as can be seen in the figures; in this position the sachet  20  is globally vertical.  
         [0043]    The hooks  15 ,  16  are oriented toward the rear in this embodiment, relative to the animal; they could instead extend toward the front.  
         [0044]    Means for applying a constant pressure associated with the sachet  20  include a weighted clamp  30  fitted around the sachet  20 ; in the embodiment shown, the clamp  30  includes two rollers  31 ,  32  which rotate on two parallel axles  33 ,  34 ; the length of the rollers  31 ,  32  is greater than the width of the sachet  20 , so that the rollers extend beyond the sachet by about 10 millimeters on each side, for example.  
         [0045]    The axles  33 ,  34  are supported laterally at their ends on bars  35 ,  36 . The rollers  31 ,  32  are made from a rubber-like material or at least carry an elastomer coating, advantageously a flexible elastomer coating, so that when the sachet  20  is introduced between them they press the walls of the sachet  20  together in a sealed manner; the rubber-like material also adheres to the plastics material walls and the clamp  30  can therefore move up or down the sachet  20 , in accordance with positive or negative uterine contractions, as described below.  
         [0046]    The device in accordance with the invention is used in the following manner.  
         [0047]    With the female  11  wearing the saddle  12 , the clamp  30  is fitted to the sachet  20  by inserting the top part of the sachet  20  between the rollers  31 ,  32  of the clamp  30 ; the rollers  31 ,  32  pinch the walls of the sachet  20  and descend along them to a level above the level  23  of the semen contained in the sachet  20 ; the air trapped in the sachet  20  is therefore confined in a pocket  25  defined between the level  23  of the semen and the generatrices of the cylinders  31 ,  32  in mutual contact; the sachet  20  is then suspended from the hooks  15 ,  16  on the arm  14  by its holes  21 ,  22 .  
         [0048]    In this position of the sachet  20 , the pressure of the air in the pocket  25  depends on the weight of the clamp  30 , which can be calibrated: it is sufficient to provide a set of clamps  30  of different weights, e.g. equipped with rollers of different weights, staggered by 50 g to 1000 g, for example, to adapt the pressure and/or the insemination time to different sows, for example of different breeds; the pressure is moderated and controlled in this way.  
         [0049]    A probe  24  is then introduced in the conventional way into the bottom part of the sachet  20  and into the neck of the uterus of the female  11 .  
         [0050]    Clearly, as the semen descends into the uterus of the female  11 , i.e. as uterine contractions occur, the rollers  31 ,  32  descend the sachet  20 , the air pocket  25  pushing down the semen, the pressure in it remaining constant, of course, during inward contractions of the uterus of the female; during outward contractions, the rollers  31 ,  32  rise up the sachet  20 , pushed up by the rising pocket of air  25 , which is in turn pushed up by the semen; movement of the clamp  30  is clearly perfectly synchronized with the contractions of the uterus of the female  11 .  
         [0051]    Thanks to the device according to the invention, insemination is simple, efficient and can be controlled visually; it is no longer a question of forcible injection, as in some prior art methods; here it is the onset of uterine contractions, indicating that the animal is on heat, that initiates movement of the clamp  30 .  
         [0052]    Because the device in accordance with the invention does not come into contact with the uterus or the animal semen, it can be used again without cleaning it; there is no risk of contamination or genetic mixing; made of flexible material, it is compact.  
         [0053]    Note also that the elastic clip  17  of the device  10  clamps the flanks of the female  11 , so stimulating uterine contractions.  
         [0054]    FIGS.  3  to  6  show a variant of the device according to the invention.  
         [0055]    Here, instead of being in the form of a plate, as in the previous embodiment, the base  113  is formed by extending and deforming the strand  29  of the wire constituting the sides  18  and  19  of the clip  17 ; the free ends of the wire and its middle part are joined, for example welded, to the bracket  27 , which has two vertical flanges linked by a pin  41  on which the arm  14  pivots by means of a slot  42  in the small plate  43 ; to be more precise, the base  113  is defined by two sections  46 ,  47  aligned with the flanges of the bracket  27  and connected, here at right angles, to two sections  48 ,  49  axially aligned with each other; the sections  46 - 47 - 48 - 49  are coplanar, as is also the middle part  50  of the U-shaped strand  28 ; oblique sections  51 ,  52  connect the sections  48 ,  49  to the remainder of the strand  29  of the sides  18 ,  19 .  
         [0056]    Notches of different depth are provided at the rear end of the top edge of the small plate  43 ; in this example there are two notches  44  and  45 , spaced in the direction of the arm  14  and adapted to cooperate with a pin  26  carried by the base  27  between its two flanges.  
         [0057]    The arm  14  can therefore assume different inclinations, as can be seen in FIGS. 3 and 5, on the one hand, and in FIGS. 4 and 6, on the other hand, enabling the sachet  20  to be placed in an ideal, so-called insemination position corresponding to the nulliparous or multiparous female to be inseminated. In FIGS. 3 and 5, the shallower notch  44  cooperates with the pin  26  and in FIGS. 4 and 6 the deeper notch  45 ; in these latter figures, the arm  14  is inclined farther toward the rear.  
         [0058]    As can be seen, the various positions of the arm  14  are obtained without any demounting.  
         [0059]    The length of the slot  42  is such that by pulling the arm  14  outward the small plate  43  can be disengaged completely from the pin  26 ; the arm  14  can then be folded completely down, passing between the sections  46  and  47  to lie inside the clip  17 , parallel to the sides  18 ,  19 , in a storage configuration.  
         [0060]    When the device  10  is fitted to an animal, a so-called rest position of the arm  14  can be obtained by pivoting the arm  14  completely toward the front of the animal until the small plate  43  cooperates with the pin  26 .  
         [0061]    Everything just stated with reference to the base shown in FIGS.  3  to  6  is valid for that shown in FIGS. 1 and 2, in which the base is in the form of a plate and has a notch open toward the rear for the arm to pass through.  
         [0062]    Here the hooks  15 ,  16  are carried by an elastic clip  38  which fits tightly around the arm  14  so that its position along the arm can be varied and can be chosen so that insertion of the probe  24  is facilitated and so that the probe extends from the sachet in a globally parabolic line, which encourages the flow of semen.  
         [0063]    [0063]FIGS. 7 and 8 show another embodiment of a device according to the invention.  
         [0064]    In these figures, components identical to or having the same function as those of the previous embodiments carry the same reference numbers increased by 100 or 200.  
         [0065]    Here the clip  117  is of the kind shown in FIG. 1, and is made from wire bent to shape, the sides  118 ,  119  being doubled back on themselves, the wire having two generally parallel strands  128 ,  129  that are spaced by 6 mm or 7 mm, for example. The sides  118 ,  119  are also bent inward; here each of them has four practically straight sections A, B, C, D with an obtuse angle between successive sections (see FIG. 8); note that the joins are abrupt, the wire being bent with no radiusing, which avoids deformation of the sides  118 ,  119  in use and consequential reduction of the spring effect which applies pressure to the flanks of the animal.  
         [0066]    Here the base  213  is in the form of an elongate open loop of wire articulated to the clip  117 ; to be more precise, the ends  214  (FIG. 7) of the open loop are wound around virtually horizontal segments A of the strand  128  of the sides  118 ,  119 ; the base  213  stabilizes the saddle in the operational position; in this position, shown in FIG. 7, the base  213  is under the bracket  27  and under the strand  129  of the side  118 ,  119  which is the rear strand relative to the animal; also, the base  213  is under the arm  114 , and therefore toward the rear of the animal; in this position, the base  213  prevents the saddle tilting and sliding toward the rear because of the weight of the sachet  20  and the clamp  30 ; also, the elongate open loop shape of the base  213  enables it to straddle the spine of the animal, which locates and immobilizes the saddle transversely.  
         [0067]    Here the arm  114  has its free end in the form of a ring  115  to facilitate grasping it.