Patent Publication Number: US-2003229312-A1

Title: Inoculation apparatus and method

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
     [0001] This application is a continuation patent application of patent application Ser. No. 09/489,546 filed on Jan. 21, 2000. 
    
    
     
       BACKGROUND OF THE INVENTION  
       [0002] The invention relates to an apparatus for inoculating small animals, e.g., fowl or poultry such as chickens, turkeys, guineas, geese, ducks, pheasants, quails, etc. when they are young.  
       [0003] Domestically raised poultry are subject to various diseases and infections after hatching. For the effective raising of such poultry, they need to be inoculated to reduce loss of poultry and to insure efficient growth. When a disease or infection starts in a flock, it can quickly spread to the remainder of the birds causing catastrophic loss, sometimes of the entire flock. Oftentimes the profit margin on poultry is low, so even the loss of a few birds or their failure to grow efficiently, can have a substantial adverse effect on overall profits. There is thus a need for an apparatus to quickly and efficiently inoculate a large number of birds with a high level of confidence that all or substantially all of the birds have been effectively inoculated. For example, it is desired to effectively inoculate at least 99% of chicks born into a flock.  
       [0004] Devices for inoculating poultry by automatic injection of inoculants through a hypodermic needle and syringe are well known in the art. Such a device and corresponding method are disclosed in U.S. Pat. No. 5,311,841, (incorporated herein by reference). The disclosed method provides a major advance in the effective inoculation of poultry when they are in the chick stage. The inoculation, according to the disclosed method, is done when the chicks are young and still have their yolk sacs. The yolk sac is relatively small on the major surface and thin and the needle needs to be accurately directed and positioned to insure the tip of the needle is located in the sac when the inoculants are injected. In order to handle the large number of birds encountered at a typical large poultry farm, the device needs to be quick and efficient to use. However, the bird needs to be properly positioned relative to the injection needle and relative to the ground and held in that position for proper inoculation. Also, the inoculation device needs to include a positive trigger mechanism to automatically activate the syringe and needle.  
       [0005] Because many birds will be processed in succession, there is a need to sanitize the needle without stopping inoculation to effect sanitizing. It is preferred that the needle be continuously sanitized with minimal clean up and waste of disinfectant. Sanitization is known, see for example, U.S. Pat. No. 4,515,590 wherein a sprayer is used to sanitize the needle. This system however requires cleanup of the spray from inside the housing and is sprayed at intervals. Also, the exterior surface of the needle is not wiped during such spray cleaning.  
       [0006] The working environment in poultry farms is oftentimes wet. This presents concerns for worker safety particularly when using power operated devices since many are powered at least in part by electricity. It would be desirable to eliminate the risk of electrical shock to workers by providing an inoculator that can be operated without the use of electricity and still provide the ability to have an effective automatic operation control system.  
       [0007] Various types of medicaments are used for inoculation. Some medicaments are mixed together so that only one injection is required to complete the inoculation. However, it has been found that the medicaments can physically separate whereby the inoculant is not uniform throughout the container. The inoculant needs to be agitated or otherwise mixed, preferably continuously, to insure uniformity and thereby effectiveness of the inoculation. Thus, there is a need for an inoculating device that insures uniformity of inoculant when injected. Further, the agitation is desirably achieved without the use of electricity at the inoculator.  
       [0008] Many devices are available for such inoculations but have one or more of the above described drawbacks. Thus, there is a need for an apparatus and method for improved inoculations.  
       SUMMARY OF THE INVENTION  
       [0009] Among the several objects and features of the present invention may be noted the provision of an inoculation apparatus that improves upon the currently available devices; the provision of an inoculation apparatus that is easy and efficient to use; the provision of an inoculation apparatus that reduces the need for stopping inoculation to sanitize the needle and that provides an improved sanitizer that can clean the needle between each injection; the provision of an inoculation apparatus that is effective and efficient in inoculating large numbers of birds in a short period of time; the provision of an inoculation apparatus that provides improved positioning of the bird relative to the needle and horizontal (the ground) for inoculation; the provision of an inoculation apparatus which reliably triggers movement of the hypodermic needle to the extended or inoculating position; the provision of an inoculation apparatus that eliminates the risk of electrical shock while providing an automatic operation control system; and the provision of a method of inoculation that stabilizes and enhances the inoculation target area of the bird.  
       [0010] One aspect of the present invention includes an apparatus for injecting an object with a fluid. The apparatus comprises a hypodermic syringe and a needle mounted on the syringe. The needle is movable on a drive path for injection of the object. Drive means connect to the hypodermic syringe and are operable to selectively move the needle between an extended position and a retracted position. A conduit for flow of fluid has an outlet for flow of fluid therethrough. The outlet is positioned relative to the needle so that an object in the drive path of the needle may partially block the outlet to restrict flow of fluid through the outlet. A pressure sensor for sensing a change in pressure in the conduit resulting from restriction of fluid flow through the outlet activates the drive means whereby the drive means moves the needle to the extended position in response to the change in pressure.  
       [0011] Another aspect of the present invention includes an apparatus for injecting a small animal with a fluid, wherein the animal has an abdominal area. The apparatus comprises a hypodermic syringe and a needle mounted on the syringe. The needle is movable on a drive path for injection of the animal. A cradle adjacent the needle is adapted for positioning the animal to be injected in a face up position relative to the needle so that the abdominal area of the animal is exposed for penetration by the needle. Drive means connected to the hypodermic syringe are operable to selectively move the needle between an extended position and a retracted position.  
       [0012] Yet another aspect of the present invention includes an apparatus for injecting a small animal with a fluid. The apparatus comprises a hypodermic syringe, a needle mounted on the syringe and a drive means connected to the syringe. The drive means is operable to selectively move the needle between an extended position and a retracted position. A positioning device positioned adjacent the needle is adapted for positioning the animal to be injected relative to the needle. The positioning device includes a cradle extending from the housing and opening generally upwardly. The cradle has a portion defining an opening for receiving a posterior portion of the animal to facilitate positioning the animal relative to the needle.  
       [0013] Other objects and features will be in part apparent and in part pointed out hereinafter. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0014]FIG. 1 is a perspective view of an apparatus for inoculating small animals;  
     [0015]FIG. 2 is a fragmentary plan view of the inoculating apparatus with portions broken away to illustrate components mounted inside the apparatus;  
     [0016]FIG. 3 is a front end view of the apparatus showing a cradle on one end of the apparatus;  
     [0017]FIG. 4 is a schematic diagram of the control circuit and cylinders used to operate the apparatus;  
     [0018]FIG. 5 is an enlarged fragmentary view of the hypodermic needle sanitizing device shown in side elevation;  
     [0019]FIG. 6 is an enlarged fragmentary view of a device for agitating the inoculant; and  
     [0020]FIG. 7 is an enlarged view of the syringe with portions broken away to show internal detail of the syringe. 
    
    
     [0021] Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.  
     DETAILED DESCRIPTION  
     [0022] The reference numeral  10  (FIG. 1) designates generally apparatus for inoculating small animals  12  such as poultry, including, chickens, turkeys, ducks, geese, guineas, pheasants, quails, etc. Preferably, poultry is inoculated when it is young and still has a yolk sac that is positioned in the abdomen of the bird. The apparatus  10  generally includes a housing or frame  14 , a syringe  16 , a hollow needle  18 , a drive  20  operable to move the needle  18  along a drive path between an extended position and a retracted position (FIGS. 1, 2 and  7 ). The apparatus  10  also includes a trigger mechanism, designated generally as  22 , that actuates movement of the needle  18  (FIG. 3). A retention or work platform  24  which includes a cradle  25  is provided in which the animal  12  is placed for locating it in the drive path relative to the needle  18  for inoculation when the needle moves to its extended position along the drive path (FIGS. 3 and 5). To maintain the needle  18  sanitized, a needle sanitizer, designated generally as  27 , is provided. Inoculant  29  is contained in a container  30  and is fed to the needle  18  through the syringe  16  as is known in the art. The inoculant  29  in the container  30  is maintained mixed by an agitation device, designated generally as  32 , carried by the housing  14 .  
     [0023] The housing  14  includes a first case  34  for containing the operation control system (hereinafter described). The case  34  includes six walls (designated respectively by the reference numerals  35 - 40 ) and is a generally rectangular solid in shape. One or more walls can be removable to provide access to the interior of the case  34 . As shown, the top wall  40  and one end wall  39  are connected together forming a lid that can be separated from the remainder of the case walls by removal of the screws  41 . A pressure gauge  43  is mounted in a side wall  36  so it can be viewed by an operator. Also, adjustable controls, including the pressure regulator knob  44 , the counter  45 , the master control switch  46  and a reset operator  47  are mounted on the case  34  and as shown, the knob  44  is mounted above the wall  40  and the counter, control switch and reset operator are mounted on the wall  36  for manipulation by the operator of the apparatus.  
     [0024] The housing  14  also includes a second case  51 . Preferably, the second case  51  houses various moving parts and operation control devices (hereinafter described) of the apparatus  10  and like the case  34 , has six walls (designated respectively by the reference numerals  53 - 58 ). Preferably, the top wall  57  is movable or removable to provide access to the interior  60  of the second case  51  and the parts mounted therein. As shown, the top wall  51  is a lid hingedly mounted on the end wall  56  with a hinge  62  for pivoting movement between open and closed positions. Two ports  64  are provided through the top wall  57  for conduits  66 ,  67  to extend through to be connected to the syringe  16  and a disinfectant pump (hereinafter described). Preferably, the housing  14  is made of metal such as stainless steel which is easy to clean and is corrosion resistant. The cases  34 ,  51  are joined together at a joint by suitable fasteners, such as toggle clamps  71 . The first and second cases  34 ,  51  can thus be separated for maintenance, cleaning, etc. The second case  51  preferably contains no control circuit devices that can be damaged by cleaning and is separated from the first case  34  for cleaning, e.g., by immersion in a cleaning liquid. The case  51  has a bottom wall  54  that is angled from horizontal (the ground) at an angle A in the range of about 20° through about 60° and preferably in the range of about 30° through about 45°.  
     [0025] As seen in FIG. 2 the apparatus  10  includes the hypodermic syringe  16 , such as a model 516000 syringe made by Wings. The syringe  16  is mounted in a guide support  76  for linear movement between an extended position and a retracted position. The syringe  16  has the hollow hypodermic needle  18  mounted on the forward end (FIG. 7). The needle  18  is connected in fluid flow communication with a metering chamber  78  in the syringe  16 . The metering chamber  78  is in turn connected in fluid flow communication to the source of inoculant  29  or vaccine, which is shown as the container  30 , via the conduit  66 . The inoculant  29  flows by the influence of gravity from the container  30  to the syringe  16  metering chamber  78  or could be pumped if desired. Pumping can be done at least in part by negative pressure created in metering chamber  78  when a piston  79  moves from its extended position to its retracted position. A check valve  77  is provided between the conduit  66  and metering chamber  78  to prevent flow of inoculant from the chamber back into the conduit during inoculation.  
     [0026] The syringe  16  includes the piston  79  with a plunger  80  extending out of the rearward end of the syringe. The piston  79  is spring loaded to return the piston to a rearward or retracted position. A spring  82  is positioned between a syringe housing  83  and a shoulder formed by a connector  85  and is normally compressed providing force to help return the piston  79  to the retracted position. Drive  20  is provided and is operably connected to the syringe  16  to effect linear movement of the syringe  16  and needle  18  between their retracted positions (shown in FIG. 2) and extended positions. A preferred drive  20  includes a pneumatic cylinder  87  that is connected to the syringe  16  by the connector  85 . Preferably the connection provides for easy connection and disconnection of the syringe  16  from the cylinder  87 . As shown, the cylinder  87  has a coupling  89  connected to its piston rod  90 . The coupling  89  is preferably made of a plastic such as nylon. The coupling  89  includes an open channel  92  which receives the syringe connector  85 . The connector  85  and coupling  89  are retained against relative longitudinal movement by an E-ring  93  mounted on the plunger  80  and received in a groove  94  in the coupling  89 . This arrangement permits easy disconnection by moving the connector  85  and E-ring  93  out through the opening  95  of the channel  92 . The width of the opening  95  is smaller than the diameter of the connector  85  whereby the connector  85  is releasably retained in the coupling  89 .  
     [0027] A base plate  101  is mounted in the case  51  in a manner that will permit its selective movement. The base plate  101  is mounted so it can be moved transversely of the case  51 . As seen in FIG. 2, the base plate  101  is generally rectangular having opposing longitudinal side edges  102 ,  103  and opposing end edges  104 ,  105 . The side edges  102 ,  103  each have a plurality of spaced slots  107  extending transversely into the base plate  101  from a respective side edge  102 ,  103 . A fastener  108 , such as a screw, extends through each slot  107  and is received through a respective aperture in the bottom wall  54  and is secured in place, as with nuts  109 , thereby securing the base plate  101  in place inside the case  51 . The slots  107  allow the base plate  10  to be positioned in a desired transverse position. The base plate  101  also has an elongate groove  111  extending longitudinally of the base plate  101  between the end edges  104 ,  105 .  
     [0028] The guide support  76  is secured inside the case  51  in any suitable manner for selective longitudinal movement in the case. The guide support  76  includes a generally U-shaped frame comprising a pair of upright legs  114 ,  115  and a base  116 . As shown, the base  116  is received in the groove  111  for linear movement therein. The base  116  has an elongate slot  118  therethrough. A mechanical fastener such as a stud  119  secured in the base plate  101  extends through the slot  118 . A threaded fastener such as a wing nut  120  is threaded onto the stud  119  and when tightened, fixes the longitudinal position of the guide support  76  on the base plate  101  in the case  51 . The edges of the groove  111  prevent rotational movement of the guide support  76  about the stud  119  on the base plate  101 . The transverse movement of the base plate  101  and the longitudinal movement of the guide support  76  on the base plate  101  permit the transverse and longitudinal adjustment of the position of the guide support  76  and components mounted thereon including the needle  18 . Also, the base plate  101 , guide support  76  and components are removable from the housing  51  facilitating repair, maintenance and cleaning.  
     [0029] The cylinder  87  is mounted on the leg  114 . The syringe  16  is movably mounted on the leg  115  in a race  122  for linear movement therein. The race  122  has an open top  123  and has a round through bore with a diameter slightly larger than the diameter of the syringe  16  therein for a slip fit. The open top  123  is smaller transversely than the syringe  16  diameter so that the syringe is releasably retained in the race  122 . Preferably the race  122  is made from a low friction material such as Delrin, a self lubricating plastic. The cylinder  87 , piston and piston rod  90  are coaxial with the syringe  16 , piston  79  and needle  18 . Movement of the cylinder piston forward first moves the syringe  16  forward in the race  122  until a flange  125  on the syringe  16  engages the guide support  76 . A resilient cushion  126  such as an O-ring can be positioned on the syringe  16  between the flange  125  and the guide support  76  to cushion the impact therebetween. The forward motion of the syringe  16  and needle  18  stop when the flange  16  (or O-ring  126 ) engages the guide support  76 .  
     [0030] After forward movement of the syringe  16  and needle  18  stop, the forward motion of the cylinder piston rod  90  continues. With the forward motion of the syringe  16  stopped, the syringe piston  79  then begins to move forward within the syringe  16  in the chamber  78  compressing the spring  82 . Inoculant  29  contained in the syringe chamber  78  is pressurized and ejected through the needle  18  and into the animal to be inoculated. As seen in FIG. 7, the syringe  16  includes a valve  128 . The valve  128  is preloaded with the bias of a spring  129  to hold the valve element  130  in engagement with the valve seat  131 . When a predetermined pressure is reached in the syringe chamber  78 , the bias is overcome and the inoculant in the chamber  78  flows through the needle  18 . The use of such a pressure release valve  128  prevents the inoculant  29  from flowing through the needle  18  until the predetermined pressure is attained thereby preventing leaking. A pre-measured dose of inoculant  29  is delivered because the syringe  16  is a positive displacement pump. The retraction of the needle  18  from its forward most position is fast enough to prevent drawing liquid contents of the animal back into the needle. The syringe  16  can have the volume of the inoculant chamber changed, as is known in the art, for example by providing a syringe piston  79  of a different length changing the volume of the syringe chamber  78 . A typical inoculation dosage for a chick is in the range of about 0.1 ml through about 0.5 ml and preferably about 0.2 ml.  
     [0031] Preferably the cylinder  87  is a single acting cylinder with spring return. Pressurized air from an air source  133  is supplied from the source through a pressure regulator  137 , a conduit  134  and a control valve  135  to selectively move piston rod  90  of the cylinder  87  to its extended position (FIGS. 2 and 4). The spring in the cylinder  87  will return the piston  79 , needle  18  and syringe  16  to their retracted positions when the pressurized air in the cylinder is released through an exhaust port in the on-off switch  46 . Also, the cylinder  87  could be a double acting cylinder, if desired, using pressurized air for extension and retraction.  
     [0032] A needle guide tube  139  is secured to the case  51  and is positioned to permit the needle  18  to move therethrough between the extended and retracted positions of the needle (FIGS. 2, 3 and  5 ). The guide tube  139  has a nipple  140  that projects outwardly from the end wall  58  a distance in the range of between about 0.5 through about 0.75 cm. The guide tube  139  is suitably secured to the wall  58  such as by welding. The elongate bore  142  through the guide tube  139  is coaxial with the needle  18  and the needle is preferably positioned in the approximate center of the bore  142 . The retracted position of the needle  18  preferably leaves the needle point inside the guide tube  139 . For chicks, the needle  18 , in its extended position, extends from the distal end  141  of the guide tube  139  a distance in the range of about 2 mm through about 3 mm as measured from the rearward end of the bevel on the needle end to the distal end  141  of the guide tube  139 .  
     [0033] The nipple  140  is positioned above the upwardly facing support surface  168  of the cradle  25  a distance D′ in the range of about 1.5 cm and about 2.0 cm as measured from the lower most disposed portion of the surface  168 . The nipple  140  is preferably generally round in transverse cross section and has a diameter in the range of about 0.25 cm through about 0.4 cm at least at the distal end  141 .  
     [0034] The apparatus  14  is provided with means  27  for sanitizing the needle  18 . As shown in FIG. 5, a porous member  143  is installed or mounted in an enlarged bore  144  in a tubular housing  145 . The bores  142 ,  144  are preferably generally coaxial. The housing  145  is secured to the nipple  140 . The porous member  143  is preferably soft for penetration by the needle and can be made of, e.g., polyester felt. Also, it is preferred that the porous member  143  be in contact with the needle  18  to apply disinfectant  147  directly to the needle and wipe the needle of debris. The bore  144  of the housing  145  and hence the porous member  143  are connected in flow communication with a source  148  of disinfectant  147  such as alcohol. The porous member  143  absorbs disinfectant  147  and holds disinfectant metered to it for subsequent application to the needle  18 . It is preferred that the disinfectant  147  be fed to the porous member  143  in a positive and metered fashion to insure adequate application but not over application of the disinfectant to the needle  18 . A preferred metering system includes a pneumatic positive displacement pump  69  such as piston pump. A suitable pump  69  is a model N700500 made by Wings. The pump  69 , when activated, will deliver a predetermined amount of disinfectant  147  to the porous member  143  via a conduit  151  connecting the pump in flow communication with the porous member. It is preferred that the pump  69  be activated by the cycle counter  45 , such as a Wings model 501000, to operate the pump sequentially. The counter  45  is operable to count the number of needle movements and hence inoculations. The preferred counter  45  is a count down counter. When a preset number of cycles has been achieved, e.g.  100 , the counter  45  activates a valve  153 . The valve  153  is shown as part of the counter reset  47 . The valve  153  allows air to flow to a pneumatic cylinder  154  connected to the pump  69  to effect a pump stroke and delivery of a predetermined amount of disinfectant to the porous member  143 . The pump  69  is in flow communication between the source  156  of disinfectant and the porous member  143  via conduits  151 ,  67 . Preferably, the pump  69  has built in valving to prevent flow of disinfectant  147  to the porous member  143  without pump activation and prevent flow back to the source of disinfectant during pumping. A check valve  157  prevents back flow to the source  156 , such as a container, and a pressure release valve  158  is in the outlet of the pump  69 . The pressure release valve  158  prevents flow until a predetermined pressure is reached in the pump  69 . This prevents flow of disinfectant  147  to the porous member  143  until the pump  69  is activated to pressurize the disinfectant  147  in the pump. The porous member  143  will apply the disinfectant  147  to the needle  18  on every movement of the needle even though the disinfectant is supplied to the porous member incrementally or sequentially. By controlling the feed of disinfectant  147  and applying the disinfectant directly to the exterior of the needle  18 , little if any waste of disinfectant occurs and there is little if any disinfectant to clean up.  
     [0035] As shown, the container  156  is mounted in a stand  160  that is suitably mounted on the case  34 . The container  156  is positioned at an elevated position relative to the pump  69  and the porous member  143  to allow gravity to induce flow of the disinfectant  147  to the pump  69  and hence the porous member  143 . The use of the pump  69  insures positive delivery of disinfectant  147  and also permits intermittent delivery in a controlled manner. As shown, the pump  69  is mounted in the case  51  by suitable securement to the side wall  55 .  
     [0036] To insure effectiveness of the inoculation, particularly when injecting into the yolk sac, the bird being inoculated needs to be positively and properly positioned relative to the needle  18 . The work platform  24 , as best seen in FIGS. 1 and 3 is provided to position the chick  12  relative to the needle  18  for inoculation. The work platform  24  includes the cradle  25  secured to the wall  58  adjacent the guide tube  139 , nipple  140  and the trigger mechanism  22 , for example with mechanical fasteners  163  through laterally extending ears  164 .  
     [0037] The cradle  25  projects outwardly from the wall  58  and is upwardly opening for ease of bird positioning. The cradle  25  is in the shape of a trough that is arcuate in transverse cross section. The cradle  25  is preferably sized and shaped such that when a chick is placed therein, the yolk sac will maintain its shape and position to help insure proper inoculation when the abdomen is placed against the distal end  141  of the nipple  140 . For use with chicken chicks, the cradle  25  has a length L of about 3 cm, a width W at the open top of about 3 cm and a depth D of about 1 cm. The cradle  25  is preferably made of metal such as stainless steel to facilitate cleaning.  
     [0038] A hatch or opening  166  is provided at the juncture between the cradle  25  and the end wall  58  and extends longitudinally into the cradle  25  toward a free (e.g., outer or distal) end  169  of the cradle. The opening  166  is positioned in the lower most portion of the cradle  25  and under the nipple  140 . The opening  166  facilitates positioning of the bird  12  relative to the needle  18  and the nipple  140  and allows for a more sanitary structure during operation to prevent the collection or build up of vented waste. The opening  166  is shown as an elongate slot and is sized to receive the tail portion or posterior  167  of a chick  12 . The opening  166  has a width in the range of between about 0.8 cm through about 1 cm and a length, as measured from the end wall  58 , in the range of between about 0.9 cm through about 1.1 cm. A crossbar  165  is secured to the cradle  25  adjacent the end wall  58  and the opening  166  and is preferably arcuate and spaced from the support surface  168  of the cradle. The maximum spacing between the crossbar  165  and the support surface  168  is located above the opening  166  and is in the range of about 0.7 cm through about 0.9 cm. The crossbar  165 , support surface  168  and the edges of the opening  166  form a yoke for receiving and restraining the rearward or posterior end  167  of a chick  12  against movement while forcing the chick&#39;s tail portion downward and abdomen up to help position the yolk sac.  
     [0039] The cradle support surface  168  is preferably inclined upwardly relative to horizontal. It has been found that having a chick  12  inclined with the head of the chick  12  at the high end as opposed to horizontal reduces struggle by the chick during inoculation. This inclined position is also more ergonomic for the operator. The angle of incline A′ is that angle between the longitudinal axis of the cradle  25 , which is generally parallel to the lowermost disposed portion or nadir of the support surface  168  extending between the opposite end of the cradle, and horizontal and is in the range of about 20° through about 60° and preferably in the range of about 30° through about 45°. The needle  18  moves in a path generally parallel to or in a plane that extends generally vertically through the longitudinal axis of the cradle  25 . It also moves at an angle A″ relative to the longitudinal axis of the cradle  25  in the range of about −5° (downwardly and away from the longitudinal axis) through about 5° (upwardly and away from the longitudinal axis) as seen in FIG. 5. The preferred angle A″ is in the range of about +1° through about +3°. The chick  12  has a coronal plane that is generally parallel to it backbone. Thus, the coronal plane of the chick  12 , when in the cradle  25 , is positioned at an angle relative to horizontal in the range of about 20° through about 60° and preferably in the range of about 30° through about 45°.  
     [0040] The work platform  24  includes an arcuate fence  170  secured to and extending between opposite sides of the cradle  25  at the wall end of the cradle. The projection height H (in the longitudinal direction of the cradle  25  as seen if FIG. 5) of the fence is in the range of about 1.5 cm through about 2.0 cm. The fence  170  and the cradle  25  cooperate to form a generally circular ring adjacent to the end wall  58 . The diameter of the ring is in the range of between about 3.0 cm through about 4.0 cm and can be adjusted via the screw  171 . The fence  170  helps position the bird by surrounding the abdomen area so the abdomen is aligned and constrained for penetration by the needle  18 . The needle  18 , nipple  140 , and the trigger mechanism  22  are positioned inside the ring formed by the fence  170  and cradle  25 .  
     [0041] The trigger mechanism  22  is operably connected to a control circuit operable to activate or otherwise trigger movement of the needle  18  between its extended and retracted positions. As seen in FIGS. 3 and 4, the trigger mechanism  22  comprises a conduit  173  in flow communication at one end with the source  133  of pressurized air and extending out through the end wall  58  below the guide tube  139  to a distal end  174  of the conduit. Air flows continuously from the source  133  of pressurized air through a flow passage  172  of the conduit  173  and out through an opening  174 ′ in the distal end of the conduit to help keep the flow passage free of debris. However, it is understood that pressurized air could flow from the environment in through the opening  174 ′ and through the flow passage  172 . The distal end  174  of the conduit  173  forms a valve seat at the opening  174 ′ and selectively cooperates with a portion of the animal  12  to form a valve that can at least partially block the flow of air through the flow passage  172 . A pressure sensitive valve  175 , such as a signal amplifier valve model VL34H20 from Festo, is connected to the conduit  173  and is operable to sense the air pressure therein. When the flow passage  172  is at least partially blocked or obstructed, the air pressure in the conduit  173  will increase. When a predetermined pressure is achieved in the conduit  173 , a controller  177 , such as a micro timer from Wings, model 552000, will be activated. The controller  177  can include an air flow rate regulator which is adjustable to control the operating speeds of the various cylinders. The sensitivity of activation of the pressure sensitive valve  175  is adjustable by adjusting the air flow through the flow passage  172  with the flow regulator  176 , such as a Festo model GR 1/8 that is connected in the conduit  173 . Activation of the pressure sensitive valve  175  allows full pressure air to flow through the conduit  187  through the valve  175  to the controller  177 . The controller  177  is operably connected to the valve  135  via a conduit  178 . When the controller  177  is activated, it in turn activates the valve  135  allowing pressurized air to flow through the conduits  134 ,  181 ,  184  from the source  133  to the cylinder  87  urging the cylinder to move the syringe  16  and needle  18  to their extended positions. The controller  177 , after a predetermined time closes the valve  135  to preclude pressurized air from reaching the cylinders  32 ,  87 . The pressurized air is exhausted through the on-off switch  46  allowing the cylinders  32 ,  87  to retract. The controller  177  is connected to the signal amplifier valve  175  via the conduit  179 .  
     [0042] A stand  190  is mounted on the housing  14  and is operable to support the container  30  of inoculant  29 . Preferably, the container  30  is positioned at an elevated position relative to the syringe  16  for gravity flow assistance. Means can be provided for keeping the inoculant  29  mixed in the container  30  during operation of the apparatus  14 . Preferably, the means is carried by the case  51  and is operable to continuously mix or agitate the inoculant  29  in the container  30 . As best seen in FIG. 6, the stand  190  is mounted in a tube  192  that is secured to the lid  40 . The cylinder  32  is mounted on the tube  190  and is preferably coaxial with the bore in which the stand  190  is mounted. As seen in FIG. 4, the cylinder  32  is connected in flow communication to the conduit  134  as is the syringe cylinder  87 . Every time the syringe cylinder  87  is activated for extension, the cylinder  32  is also activated. The piston rod  193  of the cylinder  32  moves axially inside the tube  192  moving the stand  190  and container  30  up and down with each stroke. The movement mixes the inoculant  29  in the container  30  by shaking. The movement is about ¼″. The vibration has been found adequate to keep components of the inoculant  29  from separating during operation of the apparatus  14 . When the syringe cylinder  87  retracts, so does the cylinder  32 . The cylinder  32  is then ready to be reactivated for mixing the inoculant  29 .  
     [0043] In operation, an animal  12  such as a chick is placed in the cradle  25  tail or posterior  167  first. The tail portion  167  is placed in the opening  166  and under the crossbar  165 . The abdomen is moved into engagement with the opening  174 ′ and the nipple  140 . The chick  12  is held firmly against the distal end of the nipple  140  and the valve seat at the opening  174 ′ of the distal end  174  of the conduit  173  is partially or completely blocked, raising the air pressure in the conduit. The distal end  141  of the nipple  140  engages the abdomen area of the chick at the yolk sac which is just below or to the side of where the umbilical was attached. By pressing the abdomen against the nipple  140 , the skin is stretched over the distal end  141  cinching the skin in place which facilitates entry and retraction of the needle  18 . It also helps prevent subsequent leakage of fluid from the chick at the needle entry point. The signal amplifier  175  is activated by the increased air pressure which in turn activates the controller  177  and thus the extension of the cylinders  32  and  87 . The needle  18  moves forward and penetrates the bird  12  and the inoculant  29  is injected into the bird, e.g., in the yolk sac. The needle  18  then retracts and the bird  12  is removed from the cradle  25 . After a predetermined number of injections or needle movements, a quantity of disinfectant  147  is dispensed to the porous member  143  to replenish the supply of disinfectant in the porous member. The dispensing of disinfectant  147  to the porous member  143  preferably occurs when the counter  45  reaches 0 and is reset for the preset quantity. Resetting is accomplished by activating the counter reset  47 . The needle cleaning occurs during operation of the apparatus  14  and the disinfectant  147  is contained during dispensing and application to the needle  18 .  
     [0044] The operating control system is shown in FIG. 4. The system includes the source  133  of pressurized air. It is connected by a conduit  181  to the pressure regulator  137  which preferably includes an air filter device such as a Norgren model B07-101-mika. The pressure regulator  137  is adjusted with the knob  44 . The gauge  43  is connected in the conduit  181  to show the operating pressure which is preferably in the range of between about 40 psi and about 60 psi. The main control on-off switch  46  is connected to the air supply conduit  181  and is preferably a three position valve such as a Wings model 508000. The three positions include off, on and manual. When off, no pressurized air is supplied beyond the valve  46  to the control system. When in manual, air is supplied to the cylinder  87  to move it, the syringe  16  and the needle  18  to their fully extended positions for position adjustment and/or verification of adjustment. When the valve  46  is in the on position, the control system is activated and ready to operate.  
     [0045] The flow passage  172  is at least partially blocked by an animal thereby increasing the pressure in the conduit  173 . As described above, the distal end  174  of the conduit  173  forms a valve seat at the opening  174 ′ and the chick functions as a valve seal element forming a valve on the distal end. The valve formed by the opening  174 ′ and the animal  12  is characterized by an absence of a valve seat and valve seal element contained therein. The signal amplifier valve  175  is activated which in turn activates the controller  177  which is connected in flow communication to the signal amplifier by conduit  179 . The controller  177  is connected in flow communication with the counter  45  at its count port Z and output signal port A by conduits  182 ,  183  respectively. The counter  45 , if count down, has a preset quantity and counts one activation or shot and reduces the preset count or subsequent count by one. The controller  177 , when activated by the signal amplifier valve  175  opens the valve  135  for a predetermined time to let pressurized air flow to the cylinders  32 ,  87 . Also, an alarm device such as a whistle  184 , such as Wings Model 512032 is connected in flow communication with the controller  177  and counter  45  by conduit  183 . When the zero count is reached, i.e., a predetermined number of inoculations have been made, pressurized air flows to the whistle  184  producing an alarm sound letting the operator know that the inoculations for that round or group are completed. The valve  135  is also connected in flow communication with the controller  177  via conduit  178 . Air from the controller  177  activates the valve  135  allowing air from the conduit  185  to flow thru the valve  85  and conduit  134  to the syringe and agitator cylinders  87 ,  32  forcing them to extend. As shown, the conduit  134  to the syringe is two piece allowing it to be separated at a coupling  186  mounted on the wall  38  so the two cases  34 ,  51  can be easily separated.  5  After the cylinders  87 ,  32  have extended, the pressurized air is released via the on-off switch  46  and the cylinders can return to their normal retracted positions.  
     [0046] The counter  45  is connected at the air supply port P in flow communication with the valve  46  via conduit  187 . The counter reset  47  is connected in flow communication with the conduit  187  and the counter  45  via conduit  188 . When the counter reset  47  is activated, pressurized air is supplied to a reset port Y of the counter via conduit  188 . The conduit  188  is two piece and includes a coupling  189  that is mounted in the wall  38  to facilitate separation of the cases  34 ,  5   1 . When pressurized air is supplied to the counter  45  at the reset port Y, the counter  47  is returned to its preset number or quantity and is ready to begin a new countdown series. At reset activation, the pump cylinder  154  effects pumping of disinfectant  29  to the porous member  143  from the container  156  via conduits  67 ,  5   1 . When the counter has reached the zero count, if a count down type, the system cannot be activated until the counter  45  is reset.  
     [0047] The control system also includes the flow regulator  176  connected in flow communication with the valve  46  via conduit  187  and to the signal amplifier  175  via conduit  173 . The flow regulator  176  is operable to adjust the sensitivity needed to activate the signal amplifier valve  175 . The more air that flows through the conduit  173 , the less blockage of the opening  174 ′ is needed to activate the syringe cylinder  87 , agitator cylinder  32 , controller  177  and counter  45 . The signal amplifier  175  is also connected in flow communication with the valve  46  via conduit  187  connected to the input port P′ to provide full pressure air to the downstream control circuit elements. Thus, the control circuit is completely pneumatically operated not requiring or using any electronic components.  
     [0048] When introducing elements of the present invention or the preferred embodiment(s) thereof, the articles “a,” “an,” “the,” and “said” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.  
     [0049] As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.