Abstract:
A method is provided for raising poultry, such as chickens, for food production. In a first preferred embodiment, the method includes the steps of: providing a facility for housing the poultry, providing at least one light-absorbing ventilation fan associated with the facility for ventilating the facility, exposing an interior of the facility to natural light cycles of an outside environment for a first period and regulating light cycles of the interior for a second period, thereby mimicking daylight duration variation representative of seasonal changes for stimulating sexual development of the poultry. In a second preferred embodiment, the method includes the steps of: providing a facility for housing the poultry, providing at least one light-absorbing ventilation fan associated with the facility for ventilating the facility, limiting exposure of an interior of the facility to light to produce a brown-out effect therein for enhancing physical development of the poultry.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of priority of U.S. provisional application 60/267,912, filed Feb. 9, 2001. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to methods of poultry production and more particularly to a method for enhancing poultry production. 
     BACKGROUND OF THE INVENTION 
     In various industries such as those involving agriculture, it is often necessary to circulate relatively large amounts of air through a building to help maintain the interior of the building within a desired temperature range, and to provide adequate ventilation. One such application where ventilation and control of the temperature within a building is extremely important is in connection with poultry houses. Such facilities are typically used to house chickens which are being grown for eventual slaughter or which are being used for egg production. Such facilities are also designed for manipulating the light that enters into the building. Light entering a poultry house may effect a chicken in two ways. Initially, the time frame by which a chicken becomes sexually mature is dependent upon the seasonal cycles the chicken experiences. Further, the psychological well being, and thus the physical development, of the chicken is effected by the quantity and concentration of light it is exposed to. Turkeys or other animals are also commonly kept in such houses, and may be equally as sensitive to light variation. 
     In a large scale poultry house, typically twenty thousand to twenty-five thousand chickens may be housed at a given time. If a poultry house is not properly ventilated, and the ambient temperature within it not properly controlled, the respiration of the chickens and the waste by-products within the poultry house can quickly give rise to a build up of ammonia and heat within the house which may be physiologically detrimental to the chickens. In extreme cases, such as where adequate ventilation and/or cooling is not provided on hot summer days, significant animal mortality may result. Even if mortality does not result, repeated lapses of proper ventilation and/or cooling can produce significant physiological stress on the chickens that results in inhibited growth, reduced egg production, and/or disease. Further, any concentrated areas of light shining into the poultry house will attract the chickens to that area, resulting in a crowd of chickens. This may be psychologically detrimental to the chickens which further inhibits their physical development. Any of the above conditions may result in significant financial losses to a poultry farmer. 
     In cases where the chickens are used for egg production, the sexual development of the chickens is a key aspect for production. Generally, chickens sexually mature during the onset of spring. In this way, nature provides for the eggs to be laid during appropriate climate conditions to ensure the survival of the offspring. Mass production of eggs, however, occurs throughout the year. As a result, poultry farmers seek to manipulate the maturity cycles of the chicken to enable the chickens to produce eggs year around. Manipulation of the maturity cycles is generally achieved through controlling the length of day the chickens experience. Through implementation of a light regulation program within the poultry house, the chicken&#39;s body can be manipulated into sensing the arrival of spring, regardless of the actual season. Thus, the chicken&#39;s body prepares to lay eggs in the upcoming weeks. This process holds significant financial advantages for poultry farmers. 
     In either of the above described cases, regulation of the amount of light entering the poultry house is a key element to ensure efficient poultry farming. Traditional poultry houses include a variety of features to ensure proper cooling, ventilation and the like. Such features create the opportunity for light to shine through small gaps where the features are mounted. Further, some features are themselves translucent, enabling a degree of light to pass therethrough and into the poultry house. The light that passes into the poultry house is detrimental to the efficient farming of poultry for the reasons discussed above. 
     It is therefore desirable in the industry to provide an improved method of poultry farming that eliminates the drawbacks resulting from light transmission into a poultry house. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a method for enhancing poultry production through the regulation of light the poultry is exposed to. The method of the present invention provides a poultry house for housing poultry therein. The poultry house further includes at least one exhaust fan for facilitating ventilation within the poultry house, wherein the exhaust fan includes light absorbing components for eliminating light transmitted into the poultry house. The method further provides a light regulation scheme for enhancing the growth characteristics of the poultry within the poultry house. 
     In a first preferred embodiment of the present invention, the sexual maturity of poultry is manipulated by providing a poultry house having at least one exhaust fan, wherein the poultry house is essentially impervious to light. To achieve this, the exhaust fan includes light absorbing components thereby prohibiting light to transmit through the material. A light regulating scheme is implemented for manipulating the day/night schedule that the chicken perceives. This regulating scheme includes a length of time where it is completely dark within the poultry house (i.e. night). The light absorbing components of the exhaust fan facilitate complete darkness within the poultry house. In this manner, the length of day the chicken perceives may be manipulated to stimulate egg production. 
     In a second preferred embodiment of the present invention, the psychological balance of the poultry is achieved by providing a poultry house having at least one exhaust fan, wherein the poultry house is designed to produce a dimming or “brown-out” effect during daylight hours. To achieve this, the exhaust fan includes light absorbent components thereby prohibiting light to transmit through the material. A light regulation scheme is implemented for regulating the intensity of light that the poultry experience throughout the day. Balanced, dimmed light effectively calms the poultry enabling their bodies to concentrate on proper development. 
     Accordingly, it is a general object of the present invention to provide a method for enhancing the production of poultry by regulating the light the poultry is exposed to during essential growth and developmental periods. 
     A further object of the present invention is to provide a method for manipulating the sexual maturity of poultry, year around, through implementation of a light regulating scheme. The quantity of eggs produced, and thus hatchlings born, by a group of poultry may be thereby enhanced providing significant financial gains for poultry farmers. 
     Yet another object of the present invention is to provide a method for psychologically balancing growing poultry through implementation of a light regulating scheme. Poultry that are not subject to psychological stress develop better, providing a better quantity and quality of meat. Again, significant financial gains may be realized by poultry farmers. 
    
    
     Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limited the scope of the invention. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
     FIG. 1 is an elevational view of a structure in accordance with a preferred embodiment of the present invention forming a poultry house, with a roof thereon, shown in broken-away form to illustrate various components within the poultry house not visible from the exterior thereof; 
     FIG. 2 is a perspective view of an apparatus for exhausting air from the poultry house of FIG. 1; and 
     FIG. 3 is an exploded perspective view of the apparatus for exhausting air, shown in FIG.  2 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following discussion of the preferred embodiments of the present invention is merely exemplary in nature. Accordingly, this discussion in no way is intended to limit the scope of the invention, the application of the invention or the use of the invention. 
     Referring to FIG. 1, an apparatus  10  is shown in accordance with a preferred embodiment of the present invention. The apparatus  10  described herein is the subject of commonly assigned U.S. Pat. No. 5,492,082, which is hereby incorporated by reference. The apparatus  10  is used for providing a facility  12  for housing animals within a well ventilated and temperature controlled environment. The facility  12  may be used to house a wide variety of animals such as chickens, turkeys, hogs or virtually any other animal requiring a relatively controlled temperature and light environment for adequate growth or production of food such as eggs. While the following description of the various preferred methods and apparatus of the present invention will be directed principally with reference to chickens, this is in no way intended to limit the application of the invention to such animals. Those skilled in the art will appreciate that the facility  12  described herein is readily adaptable with little or no modification for use with a wide variety of animals which may be sensitive to significant variations in ambient temperature. 
     With further reference to FIG. 1, the facility  12  includes a pair of opposing side walls  14  and  16 , a front wall  18 , a rear wall  20 , and a roof  22  shown in break-away form to illustrate the various components used therein to control ventilation, humidity, temperature and light within the confines of the facility  12 . The side walls  14  and  16  may vary greatly in length but, for a large scale poultry house, are typically approximately 400 ft. in length. The front wall  18  and rear wall  20  may also vary significantly in length but are typically approximately 40 ft. in length for a large scale poultry house. The front wall  18  typically includes a plurality of doors  24  for allowing access to the interior of the facility  12 . A side access door  26  is typically included in the side wall  16  preferably at about a mid-point of the length of the side wall  16 . Optionally included is a door  25  in the rear wall  20 . 
     The side wall  14  is typically about 8 ft.-10 ft. in height and includes a plurality of openings  28 ,  30 ,  32  and  34  over which motor-driven curtains are disposed. In the preferred embodiment illustrated in FIG. 1, opening  28  may be covered completely by a tunnel curtain  36  disposed thereover which is adapted to be raised (i.e., opened) by a suitable electrically driven motor (not shown). Openings  30 ,  32  and  34  in the side wall  14  are each covered by a plurality of side wall curtains  38 ,  40  and  42  respectively. Each of the side wall curtains  38 ,  40  and  42  are capable of being controllably raised (i.e., opened) and lowered (i.e., closed) in conventional fashion by an electrically driven motor (not shown) associated therewith. It will be appreciated by those of ordinary skill in the art that the motors for each of the side wall curtains  38 ,  40  and  42  may be electrically coupled such that the side wall curtains  38 ,  40  and  42  will be raised and lowered simultaneously by an appropriate curtain controller (not shown). Such a controller is commercially available from the assignee of the present invention. 
     With further reference to FIG. 1, the side wall  16  also includes a plurality of openings  44 ,  46  and  48 . The opening  44  has disposed thereover a second tunnel curtain  50  which, when fully lowered, completely covers the opening  44 . The opening  46  has disposed thereover a side wall curtain  52  while the opening  48  is covered by a side wall curtain  54 . It will be appreciated that each of the curtains  50 ,  52  and  54  is motor-driven, each having its own motor adapted to controllably raise and lower it in response to drive signals from a suitable curtain controller such as that mentioned above. As with the side wall curtains  38 ,  40  and  42 , the side wall curtains  52  and  54  may be driven simultaneously between completely lowered and completely raised positions provided their respective motors (not shown) are electrically coupled so as to be driven by an independent curtain controller. Similarly, the motors associated with each of the tunnel curtains  36  and  50  may be controlled by an independent curtain controller such as mentioned above to cause both of the tunnel curtains  36  and  50  to be raised and lowered together substantially simultaneously. It is also anticipated that the motors for the side wall curtains  38 ,  40 ,  42 ,  52  and  54  may be controlled in various arrangements to cause substantially simultaneous opening and closing of various combinations of the side wall curtains. 
     With continued reference to FIG. 1, the side wall  14  includes a plurality of openings  56 ,  58 ,  60  and  62  within which are disposed side wall exhaust fans  64 ,  66 ,  68  and  70 , respectively. Each of the side wall exhaust fans  64 - 70  are further oriented so as to exhaust air out of the interior of the facility  12 . 
     Each of the side walls  14  and  16  include larger openings  72  and  74  positioned opposite each other. The opening  72  has mounted therein a plurality of exhaust fans  76   a - 76   d  and the opening  74  has mounted therein a plurality of exhaust fans  78   a - 78   d . The exhaust fans  76   a - 76   d  and  78   a - 78   d  are oriented so as to draw air from inside the facility  12  and exhaust the air exteriorly with respect to the facility  12 . It will be appreciated that while a plurality of four exhaust fans have been shown as disposed in each of the side walls  14  and  16 , that one or more of the exhaust fans could optionally be disposed in suitable openings in the facility  12  as indicated in phantom in the drawing of FIG.  1 . Alternatively, all of the exhaust fans  76   a - 76   d  and  78   a - 78   d  could be disposed in the front wall  18 . The important consideration is that all of the exhaust fans  76   a - 76   d  and  78   a - 78   d  are disposed at an opposite end of the facility  12  from the tunnel curtains  36  and  50 . 
     With reference to FIGS. 2 and 3, the exhaust fan construction will be described in detail. The exhaust fan described herein is generally that described in commonly assigned U.S. Pat. No. 5,567,200, which is hereby incorporated by reference, with modification. The exhaust fans each include a housing  100  that forms a flow path for air flowing through the exhaust fan. The housing  100  has a first end portion  102  that includes a generally rectangular flange  104 . The flange  104  is operable to be mounted on the interior of the corresponding wall  14 , 16 , 18  of the facility  12 , while the remainder of the housing  100  extends through the wall  14 , 16 , 18  to the exterior of the facility  12 . The housing  100  further includes a generally conically shaped central portion  108  which serves to channel the flow of air between the interior of the facility  12  and a second end portion  110  of the housing  100 . The second end portion  110  of the housing  100  includes an annular wall  112  which defines an opening  114  in the housing  100  and has a surface feature such as an annular groove  116 . As will be more fully described below, the annular groove  116  is used to receive and position a motor mount within the housing  100 . 
     The housing  100  may be made from any suitable material. Preferably, the housing  100  is fiberglass, however, it will be understood that any other suitable materials may be used including ABS, polyethylene, polypropylene, vinyls, nylons, metal and so forth. As will be discussed in further detail hereinbelow, the material selected should be of a type that holds its integrity after long term exposure to ultra-violet (UV) light. In addition, the thickness of the material forming the housing  100  may be relatively thin. In this regard, the thickness of the housing  100  may be approximately 0.125 inches when the diameter of the annular wall  112  is approximately 24 inches. 
     The housing  100  further includes a generally conically shaped cone  118  that mechanically communicates with the annular wall  112  of the housing  100 . The cone  118  serves as a static regain cone which is used to improve the efficiency of the exhaust fan. The cone  118  may be rotomolded from a polymeric material such as polyethylene, however, other suitable materials may be used including ABS, polypropylene, vinyls, nylons, metal and so forth may also be used. As will be discussed in further detail hereinbelow, the material selected should be of a type that holds its integrity after long term exposure to ultra-violet (UV) light. Furthermore, it will be appreciated that the cone  118  may be of different shapes. For example, the cone  118  may be a blow-out cone in which the cone covers the opening  114  of the housing  100  when no air is flowing through the housing  100 , and then swings open when air is driven through the housing  100 . In such a case, the mountings for such a blow-out cone can be integrally formed in the housing  100 . As will be appreciated by those skilled in the art, one purpose of such a blow-out cone is to prevent air from flowing into the facility  12  through the exhaust fan when the fan, which is described below, is not operating. In accordance with the preferred embodiment of the present invention, a significant purpose of the cone  118  is to limit the amount of direct and indirect sunlight that would otherwise be able to shine through the exhaust fan. 
     The exhaust fan further includes a fan  120  as well as a motor  122  that is operable to drive the fan  120 . The fan  120  includes a plurality of integrally formed blades  124  that are connected to the centrally located hub assembly  126 . The hub assembly  126  includes an aperture  128  that is operable to receive the shaft  130  of the motor  122 . Upon rotation of the shaft  130  of the motor  122 , the fan  120  rotates so as to cause the blades  124  to drive air through the housing  100 . Each of the blades  124  of the fan  124  includes an end portion  132  which is located in a spaced relationship with respect to the annular wall  112  of the housing  100  as will be more fully described below. In this regard, the end portions  132  of the blades  124  are within about 0.375 inches from the annular wall  112 . As an alternative it is anticipated that the fan  120  may a belt-driven fan of a type commonly known in the art. 
     To provide means for mounting the motor  122  to the housing  100 , the exhaust fan further comprises a motor mount  134 . The motor mount  134  is operable to substantially maintain the spaced relationship between the annular wall  112  of the housing  100  and the end portions  132  of the blades  124  of the fan  120 . This spaced relationship is maintained because movement of the annular wall  112  during operation of the fan  120  is restricted by the motor mount  134 . The motor mount  134  comprises a generally first circular member  136  and a plurality of radial support members  138 . The first circular member  136  is generally circular in cross-section and is operable to be disposed within the annular groove  116  of the housing  100 . The radial support members  138  are preferably secured at approximately 90° intervals around the periphery of the first circular member  136  by a suitable means such as by welding. It will be understood, however, that the radial support members  138  may be secured at any suitable location around the periphery of the first circular member  136  so as to provide support for the motor  122 . The radial support members  138  extend from the first circular member  136  radially inward and each terminate with circular mounting end portions  140 . 
     Disposed proximate to the circular mounting end portions  140  is a second circular member  142 . The second circular member  142  is secured to the radial support members  138  by suitable means such as by welding and serve to maintain a generally planar relationship between the radial support members  138  during operation of the exhaust fan. As those skilled in the art will appreciate, the second circular member  142  may be of any other suitable shape that is able to generally maintain a planar relationship between the radial support members  138 . 
     When the motor  122  and fan  120  have been attached to the motor mount  134 , the motor mount  134  is inserted into the housing  100  in such a manner that the first circular member  136  engages the annular groove  116  of the housing  100 . It will be appreciated, however, that the motor mount  134  can also be inserted first into the housing  100  and then the motor  122  attached to the motor mount  134 . 
     The assembly of the exhaust fans will now be described. The housing  100  is formed so as to define the generally annular wall  112  which is proximate to the end portions  132  of the blades  124 . In addition, the housing  100  is formed so that the housing  100  has an internal surface contour which defines a surface feature such as the annular groove  112 . It will be appreciated, however, that other types of surface features, such as a raised channel contour, may also be used. 
     The motor mount  134  is then formed by initially forming the substantially first circular member  136  and then forming the plurality of radial support members  138 . The radial support members  138  are then secured to the first circular member  136  by a suitable means such as by welding. The motor  132  is then secured to the motor mount  134  by means of bolts  144  that extend through the circular mounting end portions  140  of the radial support members  138 . The motor mount  134  is then inserted into the housing  100  so as to cause the motor mount  134  to engage the annular groove  112 . It will be appreciated, however, that the motor mount  134  may also be initially secured to the housing  100 , after which the motor  120  is secured to the motor mount  130 . 
     A light trap  146  is optionally provided for eliminating direct light that would otherwise shine through the opening  114 . The light trap  146  is of a type commonly available in the market and includes a plurality of contoured baffles  148  that allow airflow while prohibiting light to pass therethrough. The baffles are spaced apart from one another, thereby creating a plurality of gaps therebetween for enabling airflow. The contouring of the baffles  148 , as seen in the cut-away portion of the light trap  146 , bends the light as it travels through the gaps. The light is bent at least three times by the baffles  148 , thereby prohibiting the light to travel completely through the light trap  146 . The light trap further includes a frame piece  152  for mounting the light trap  146  directly to the housing  100  at the end portion  102 . A more detailed description of the baffle plate  146  is forgone as the details of which are beyond the scope of the present invention. 
     A further option is the addition of a shutter  160  for selectively prohibiting the flow of air through the exhaust fan. The shutter  160  includes a frame  162 , across which, a series of vanes  164  are pivotally supported. The shutter  160  is mounted to the exhaust fan, whereby the frame  162  is mounted to the housing  100 . Further, the shutter  160  is preferably made from a plastic, including a gray resin. During periods of non-operation of the exhaust fan, the vanes  164  are closed, hanging downward from their pivot points with the frame  162  due to gravitational pull. In this manner, airflow is prohibited into the facility  12 , through the exhaust fan. During periods of exhaust fan operation, a pressure difference occurs between the exhaust fan side (low pressure side) and the facility side (high pressure side) of the shutter  160 , thereby causing the vanes  164  to pivot upward to an open position. With the vanes  164  in the open position, air flow is enabled through the exhaust fan. It is further anticipated that the shutter  160  is concurrently implemented with the light trap  146  described above. In this situation, the shutter  160  is mounted to the housing  100  and the light trap  146  is mounted to the facility side of the shutter  160 . 
     Again referencing to FIG. 1, each of the side walls  14  and  16  further include a plurality of relatively thin, elongated openings  80  and  82 , respectively. Preferably, the openings  80  and  82  are spaced along substantially the entire length of the side walls  14  and  16 . The openings  80  and  82  are preferably relatively small in height, and more preferably about one-half inch in height. Optionally, the openings  80  and  82  may also include a slat or louver-like elements adapted to open in relation to the degree of static pressure drop within the facility  12  caused by the side wall exhaust fans  64 - 70 . In this case the height of the louver-like assemblies may be four to six inches. 
     With further reference to FIG.  1  and turning now to the interior of the facility  12 , several of the cooling and heating devices used to control temperature, humidity and ventilation therein can be seen. A plurality of fans  84 , commonly known in the industry as “stir” fans, may optionally be included to provide an additional level of minimum air movement within the facility  12 . The stir fans  84  preferably comprise 220 volt, one-half horsepower,  36 ″ diameter fans and are preferably suspended from a truss or other similar structure supporting the roof  22  so as to be positioned relatively close to a floor  86  of the facility  12 . More preferably, the fans are suspended so that the bottom of each is disposed generally between about 3 ft. to 5 ft. from the floor  86 . Also suspended from the structure supporting the roof  22  is a pair of optional heaters  88  and  90 . The heaters  88  and  90  are also suspended so as to place them preferably about two and one-half ft.-three ft. from the floor  86 . It will be appreciated that typically a plurality of heaters greater than two will be included in the facility  12  to sufficiently warm the interior of the facility at various times. A plurality of temperature sensors in the form of thermistors  92   a - 92   f  are also suspended to preferably within about eighteen inches from the floor  86 . An optional pair of temperature sensors  93   a  and  93   b  in the form of thermistors may also be suspended or otherwise mounted exteriorly of the facility  12 , such as from a portion of the roof  22  or on one or more of the walls  14 - 20 . 
     Optionally, an evaporative cooling system such as that generally known in the industry as a “fogger”  94  may be suspended from the structure supporting the roof  22 . The optional fogger  94  shown in FIG. 1 includes 4 elongated, tubular water lines  96  (only one being shown), although it will be appreciated that a greater or lesser number of lines  96  could be used to suit the needs of specific applications. Each line  96  has a plurality of spaced apart nozzles  98  coupled in series in the line  96 . Water is supplied to each of the lines  96  via a suitable pump and suitable electrically controlled valving which is well known in the art. The nozzles  98  each emit a very fine mist which also helps to cool the interior of the facility  12 . 
     An electronic control system  99  is fixedly mounted on one of the walls  14 - 20  within the facility  12 . The controller system  99  controls operation of the tunnel curtains  36 ,  50 , the side wall curtains  38 - 42  and  52 , 54 , the side wall exhaust fans  64 - 70 , the tunnel fans  76   a - 76   d  and  78   a - 78   d , the optional stir fans  84 , the optional heaters  88 ,  90  and the optional fogger system  94 . Additionally, the electronic control system  99  is electrically coupled to the indoor temperature sensors  92 , as well as the external temperature sensors  93 . This enables the controller system  99  to monitor the temperatures at various internal areas of the facility  12  as well as at one or more areas exterior of the facility  12 . 
     The preferred embodiment of the present invention provides a method for enhancing poultry production. According to the method of the present invention, a facility is provided, such as the facility  12  described hereinabove, for housing poultry. At least one exhaust fan, of the type described hereinabove, is further provided for enabling ventilation of the facility  12 . The amount of light entering the facility  12  is regulated according to a predetermined schedule during a growth period of the poultry housed therein. In accordance with the present invention, efficient light regulation is assisted through the exhaust fans of the present invention, as described in further detail hereinbelow. The light regulation results in enhanced characteristics of the poultry thus, providing more efficient poultry production. 
     In accordance with a first alternative embodiment, the present invention provides a method for raising chickens to sexual maturity for enhancing egg production. In accordance with a second alternative embodiment, the present invention provides a method for raising chickens for more efficient production of desired meat portions. Each of the preferred embodiments utilizes light regulation, as discussed above and described in further detail hereinbelow. In order to limit the amount of natural light that enters the facility  12  each potential opening of the facility  12  must be covered. Hence, the various curtains described herein function to close the corresponding openings. Further, any of the materials and components that comprise facility  12  must be made to be light absorbent, thereby prohibiting the transmission of natural light therethrough. 
     To achieve this, the exhaust fans of the present invention are manufactured to eliminate their transparency, thus prohibiting transmission of natural light therethrough. Accordingly, an inside surface  150  of the housing  100  of each exhaust fan is coated with a dark paint. The dark paint is preferably black in color, however, it is anticipated that other dark colors may be substituted therefore. Further, the dark paint is preferably gel-coat paint applied to the inside surface  150  in layers. Again, it is anticipated that other coating methods may be substituted therefore. Coating only a single side of the housing  100  provides cost savings, in both manufacture and material, over coating multiple sides of the housing  100 . The cone in color, however, it is anticipated that another dark color may be substituted therefore. In this manner, the dark paint of the housing  100  and the dark cone  118  absorb light, thereby prohibiting the transmission of natural light through the otherwise partially translucent exhaust fans. Further, the cone  118  limits the amount of direct sunlight that would otherwise be able to shine through the exhaust fan. 
     In accordance with the first alternative embodiment of the present invention, the method of raising chickens to sexual maturity generally focuses on poultry raised to produce eggs. The physiological and sexual development of a chicken is a natural process that is a function of the length of day a chicken experiences. The method of the present invention accelerates this process by manipulating the day and night schedule the chicken experiences. In general, chickens are raised over a 21-week period in a facility, such as the facility  12 . For the first two weeks, the chickens are given all of the natural light that normally shines into the facility  12 . In this manner, the chickens are able to acclimate themselves to life in the facility  12 , learning where food and water are available, where warmth is available and becoming accustomed to living sociably with the other chickens in the facility  12 . Beginning in the third week and extending over the next eighteen weeks, a lighting program ensues whereby the light the chicken is exposed to gradually becomes longer. Initially, the lighting program limits the length of the “day” the chicken experiences, simulating winter days. Gradually, these “days” become longer, simulating the approach of spring. The gradually longer “days” cause the chicken&#39;s natural clock to anticipate the approach of spring, thus preparing the chicken sexually for laying eggs in “spring” (i.e. what the chicken&#39;s body thinks is spring). However, during the spring and summer months, the natural days are already longer. Therefore, in order for the chickens to experience a gradual lengthening of the day, and thus initiate sexual development, light entering the facility  12  must be restricted for a portion of the longer spring and summer days. Further, the light restriction must be to the point of complete darkness within the facility  12 . To achieve this, each potential opening of the facility  12  must be light restricted, as discussed above. The dark components of the exhaust fans of the present invention, as well as the baffle plate  146 , enable complete darkness to be achieved and therefore enable implementation of the lighting program in accordance with the method of the present invention. 
     In accordance with the second alternative embodiment of the present invention, the method of the present invention generally focuses on poultry raised to produce meat or eggs. Poultry raised for meat production are commonly referred to as “broilers” while poultry raised for egg production are commonly referred to as “layers”. The psychological well being of the broiler plays an important role in the quality and quantity of meat the broiler produces. Similarly, the psychological well being of the layer plays an important role in the quantity of eggs the layer produces. In general, chickens that are uncomfortable or have other psychological difficulties with their environment do not eat, drink or thus grow, as well as desired, resulting in less efficient poultry production. A significant influence on the psychological well being of a chicken is the light the chicken is exposed to. For example, if an opening of the facility  12  is not properly light restricted and light shines into the facility  12  unabated, that light will be concentrated in a particular area. As a result, the chickens, which are attracted to the light, tend to congregate in a confined space, around the light. This crowd of chickens has a detrimental psychological effect on the chickens, thus inhibiting their physical development. 
     To alleviate the psychological stress a chicken may experience during its growth, the second preferred embodiment functions in a two-fold manner through the regulation of light into the facility  12 . Due to the dark components of the exhaust fans of the present invention, light that would pass through the otherwise translucent exhaust fans is prohibited from entering the facility  12 , thus avoiding light concentrations within the facility  12 . In this manner, crowding of chickens in a confined space is avoided. Additionally, the limited light into the facility  12  creates a “brown-out” effect, dimming the overall light the chickens are exposed to. This has the effect of calming the chickens, making them more comfortable in the facility  12 . In this manner, the psychological well being of the chickens is enhanced, further enhancing their physical development. 
     The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.