Patent Publication Number: US-5291857-A

Title: Portable animal restraining device for use in medical testing

Description:
FIELD OF THE INVENTION 
     The present invention relates to laboratory restraining devices for animals, and more specifically, to portable, hand carryable restraining devices for larger quadrupedal animals. 
     DESCRIPTION OF RELATED ART 
     Quadrupedal animals, such as pigs, are used in the medical testing in a number of areas. For instance, since pigs&#39; hearts are similar to those of humans, pigs have wide applications in medical testing. 
     Medical testing animals must be restrained during injections or blood taking since stress associated with these procedures can cause the animals to run or bite. In view of the animals&#39; size, manual attempts to physically restrain the animals can be both difficult and dangerous. 
     Moreover, a restraining device suitable for use in the laboratory environment should be portable and easy to use. The device should also minimize the possibility of injury to both the laboratory worker and the animal. 
     The farrowing pen of Johansen (U.S. Pat. No. 2,630,097) is an example of a large class of inventions drawn to restraining devices to prevent sows from crushing piglets, both during birth and suckling. The design of this invention suffers from a number of deficiencies. Its large size and bulky construction make it non-portable. Its chute configuration complicates operation since the hog must be coaxed into the pen. Furthermore, the design makes no provision for human access to the hog while in the pen, although piglets can enter from underneath. 
     The combined hog trap and crate of Marshall (U.S. Pat. No. 629,865) concerns a restraining device for hogs. As in Johansen, this device also incorporates the chute configuration complicating its use. Marshall includes access doors which allow medical procedures to be performed on the hog. Opening of these access doors, however, will allow the hog to kick and possibly injure an operator; therefore, complete restraint of the hog is not possible. A further shortcoming lies in the fact that a clamping lever is required to keep the hog in the trap, a feature that could injure the hog&#39;s neck, and which requires a second operator dedicated to maintaining tension on the lever during the medical procedure. 
     The animal restrainer of Aanestad (U.S. Pat. No. 2,498,425) discloses a restraining device for calves. The principal drawback of this device is the complexity of its operation. The calf must be placed into the restrainer, its head must be placed into the nose harness, and a chain must be placed underneath the jaw. These are features which combine to deny the device any capacity for quick operation. 
     The animal holder of Shipley (U.S. Pat. No. 2,498,051) and the rabbit restraining box of Berlin (U.S. Pat. No. 4,228,765) both contemplate devices for holding rabbits during scientific experimentation. Both of these inventions are only appropriate for smaller animals however, since the animal must be essentially manhandled into the restraining boxes. Furthermore, their operation is complex since the body of an animal must be clamped into the devices. Finally, Shipley only provides access to only the rabbit&#39;s head, whereas Berlin only provides limited access to the rabbit&#39;s hindquarters. 
     SUMMARY OF THE INVENTION 
     It is an object of the current invention to provide an improved animal restraining device. 
     It is another object to provide a hand holdable, portable animal pen. 
     It is a further object to provide a portable animal pen capable of restricting movement of an animal while enabling unrestricted access to both hind quarters of the animal. 
     A portable animal restraining device, may be constructed with two side restraining members for restricting lateral movement; a front restraining member joining each of the two side restraining members, for restricting forward movement; and a rear restraining member joining each of the two side restraining members for restricting rearward movement; a top restraining member joining the two side restraining members, the rear restraining member, and the front restraining member. The rear restraining member is provided with two substantially parallel vertical slots allowing access to each rear leg of the subject animal. A subject animal is confined within the restraining device by simply manually lowering the device over top of the animal. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a top elevational view of one embodiment constructed according to the principles of the present invention; and 
     FIG. 2 is a bottom view of the embodiment shown in FIG. 1. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Turning now to drawings, FIGS. 1 and 2 show as embodiment of the present invention constructed essentially as the configuration of a box with an open bottom. The configuration has two opposing solid side walls 1 and 2 joined by both a solid front wall 3 and a solid top wall 4. A rear wall portion is formed by a bottom horizontal cross beam 5 and vertical member 6 connecting the solid top wall with the bottom horizontal cross beam. 
     Vertical member 6 is preferably positioned off-center, that is, at different, or unequal, distances from sidewalls 1, 2 in order to assure substantially complete access to one of the hindquarters while preventing the animal from squeezing out between member 6 and sidewall 2. 
     In effect, the off-center vertical member 6 joins the bottom horizontal cross beam 5 at an off-center point so that left and right slots 7 and 8 on either side of the center member are different sizes. 
     Handles 9 and 10 may be placed at both ends of the top wall to facilitate handling of the device. The device is preferably constructed of stainless steel to ease cleaning and prevent transmission of disease. The device can also be constructed of molded fiberglass. 
     The restraining device is operated by manually lifting it above an animal such as a pig, and then placing it over the pig. Either of the two hind legs of the confined pig may then be safely pulled through one of the two slots disposed on either side of the off-center vertical member to allow for example, manual administration of injections as, for example, with hypodermic needles. 
     The size and proportions of the restraining device are important. For instance, if the device is much longer than the pig, grasping a hind leg of the pig will be difficult. Also, if the device is too wide, the pig could turn around within the device after it has been placed over the pig, thereby defeating its purpose. Moreover, a device which is too short or too narrow will not properly fit over the pig. The approximate ideal relative proportions of the device should be 1:2.5:3, width:height:length. In one embodiment, a device for a 110 pound pig should be approximately 10 inches wide, 24 inches in height, and 30 inches long.