fig1 is an exploded isometric view of an animal shipment container of the invention ; fig1 a is a cross sectional view of a stack of animal shipment containers of fig1 ; fig2 a and 2b are , respectively , a side view , end view and top view of a perforated metal filter dome ; fig3 and 3a are , respectively , a top view and side view of a base tray ; fig4 a , 4b and 4c are , respectively , a top view , side view and two sectional views of a retaining ring seal ; fig5 a , 5b , 5c and 5d are , respectively , a top view , side view and sectional views of a wire mesh cover . fig6 is an exploded isometric view of an alternative embodiment of an animal shipment container ; fig7 a and 7b are , respectively , a side view , end view and top view of a filter dome ; and fig8 a and 8b are , respectively , a side view , end view and top view of a wire mesh load bearing dome . referring to fig1 animal shipment container 10 of the invention consists of a thermoformed or injection molded polyolefin base tray 12 , a load bearing filter dome 20 formed of expanded or perforated metal e . g ., aluminum or tin steel laminated to spun bonded polyester or polypropylene . also provided is a retaining seal 22 sized for sealing fit within a corresponding aperture 23 in filter dome 20 , and a wire mesh restrainer 24 adhesively fixed to a polyolefin or polycarbonate cover 26 . referring to fig1 a , a series of containers 10 can be stacked one upon the other with base tray 12 positioned over the upper surface 30 of a filter dome 20 . base tray 12 is provided with multiple protrusions 32 , e . g . six are shown , positioned closely about the sloping edges of filter dome 20 of an underlying container to thus hold a first container 10 laterally in position above a second container 10 . also provided are 1 - 3 mm detents 31 on the lower surface of base tray 12 which create an airway between two containers 10 placed on top of one another , and thus allow better air circulation . referring to fig2 filter dome 20 is formed of air permeable material having a height a , e . g . 6 . 0 inches , a length b , e . g . 24 . 25 inches , and a width c , e . g . 16 . 25 inches . aperture 23 is centrally located in the upper surface 27 of filter dome 20 , and is sized and shaped for sealing fit with retaining seal 22 ( e . g ., fig4 et seq . ), having a generally rectangular perimeter of width d , e . g . 8 . 19 inches , and rounded corners 34 . tongue regions 36 and groove regions 38 are provided for mating with retaining seal 22 . a flange 39 of width e , e . g . 0 . 53 inch , is provided around the perimeter of filter dome 20 . filter dome 20 is designed to allow rapid heat and moisture dissipation with a maximal unobstructed surface area . light is diffused through dome 20 , and flange 39 provides a positive seal at the edges of container 10 . referring to fig3 base tray 12 is formed of thermoformed or injection molded polyolefin . it has a length k , e . g . 24 . 5 inches , a width l , e . g . 16 . 5 inches , and a depth m , e . g . 0 . 68 inch . base tray 12 is generally rectangular in shape having bevelled or rounded corners 50 , and a rim 52 of height , e . g . 0 . 06 inch , around the perimeter of base tray 12 . trough 54 , positioned about 1 . 5 inches from perimeter lip 52 ( of height about 0 . 15 inch ), with a depth of about 0 . 44 inch , has protrusions 32 equally spaced therealong . inner perimeter 53 of trough 54 has a length of 17 . 94 inches and a width of 9 . 94 inches , slightly larger than that of the upper surface of filter dome 20 . protrusions 32 closely surround the sloping sides 55 of a filter dome 20 when base tray 12 of a first container is placed upon filter dome 20 of a second , underlying container . trough 54 receives and retains any excess liquid in container 10 not absorbed by any provided bedding material and further aligns stacked containers . referring to fig4 retaining seal 22 is molded from 0 . 4 inch thick , high density polyethylene or other polyolefin . seal 22 is generally square , with a width of 8 . 5 inches . corners 60 of seal 22 are rounded and inner perimeter 62 is provided with projecting regions 64 , shown in cross - section in fig4 c . regions 64 are suitable for mating with lip regions 38 of filter dome 20 . retaining ring 22 is also provided with an outer perimeter flange region 66 of width 0 . 45 inch . referring to fig5 cover 26 is thermoformed from 0 . 03 inch thick transparent polyvinylchloride or oriented polystyrene plastic , generally rectangular in shape with a width of 8 . 31 inches . the cover snap - fits into retaining ring 22 and holds optional wire mesh 24 firmly in position . protruding regions 70 are provided for mating of the cover assembly with filter dome 20 , and for mating of the cover with protrusions 64 of retaining ring 22 . non slip circular tabs 72 are provided for allowing removal of cover 26 from the dome ; and the cover may be easily , and securely , replaced in position . cover 26 snap fits into retaining ring 22 and holds wire mesh 24 firmly in position . referring to fig1 container 10 is assembled by placing each of the components in a stack as shown . a hot melt adhesive , e . g . bostick # 8330 polyolefin base , is pre - extruded around the inner part of perimeter lip 52 of filter dome 20 , and dome 20 placed within perimeter lip 52 such that flange 39 abuts lip 52 . when the components are assembled , they are clamped in place by a standard clamp or by a machine designed to hold flange 39 closely in contact with tray 12 . the assembly is then placed at a temperature sufficient to melt the adhesive ( e . g ., 152 - 176 ° f .) such that the adhesive passes through each of the layers . after cooling , the adhesive firmly holds the assembled components in their final position . retaining ring 22 is permanently attached within aperture 23 by one of adhesive as described above . wire mesh 24 is attached by glue to cover 26 and this assembly pushed into retaining ring 22 . cover 26 prevents access to the edges of wire mesh 24 , and can be readily removed , as required , from retaining ring 22 to allow access to the dome interior . other embodiments are within the following claims , for example , the filter dome may be formed from two components , and a base mat provided with the base tray , as follows . referring to fig6 animal shipment container 10 &# 39 ; of the invention consists of a thermoformed polyolefin base tray 12 &# 39 ;, a hydrophilic nonwoven mat 114 , a cut wire mesh floor 116 , a formed wire mesh dome 118 and an opaque melt blown polypropylene filter dome 120 . also provided is a retaining seal 22 &# 39 ; sized to fit sealing within corresponding aperture 123 ( in filter dome 120 ) and 125 ( in wire mesh 118 ); and a wire mesh restrainer 24 &# 39 ; adhesively fixed to a polyvinylchloride cover 26 &# 39 ;. referring to fig6 a , a series of containers 10 &# 39 ; can be stacked one upon the other with base tray 12 &# 39 ; positioned over the upper surface 130 of a filter dome 120 . base tray 12 &# 39 ; is provided with multiple protrusions 32 &# 39 ;, e . g . six are shown , positioned closely about the sloping edges of the filter dome 120 of an underlying container to thus hold a first container 10 &# 39 ; laterally in position above a second container 10 &# 39 ;. referring to fig 7 , filter dome 120 is formed of melt blown polyolefin of air permeable material , having a height a &# 39 ;, e . g . 6 . 0 inches , a length b &# 39 ;, e . g . 24 . 25 inches , and a width c &# 39 ;, e . g . 16 . 25 inches . aperture 123 is centrally located in the upper surface 127 of filter dome 120 , and is sized and shaped to sealing fit with retaining seal 22 &# 39 ;, having a generally rectangular perimeter of width d &# 39 ;, e . g . 8 . 19 inches , and rounded corners 134 . tongue regions 136 and groove regions 138 are provided for mating with retaining seal 22 &# 39 ;. a flange 139 of width e &# 39 ;, e . g . 0 . 53 inch , is provided around the perimeter of filter dome 120 . filter dome 120 is designed to allow rapid heat and moisture dissipation with a maximal unobstructed surface area . light is diffused through dome 120 , and flange 139 provides a positive seal at the edges of container 10 &# 39 ;. referring to fig8 load - bearing wire mesh dome 118 generally has an identical shape to filter dome 120 and is formed of galvanized steel wire mesh with a monocoque ( i . e ., load - bearing ) structure . it has a width h , e . g . 16 . 19 inches , a height f , e . g . 9 . 44 inches , and a length g , e . g . 24 . 19 inches . the corners of mesh dome 118 are bevelled , and sides 155 slope at an angle of about 75 °. centrally located aperture 125 is generally square with a width i , e . g . 7 . 63 inches , and has rounded corners 42 , tongue regions 144 , and groove regions 146 . groove region 144 has a width j , e . g . 0 . 53 inch . a flange 148 of width k , e . g . 0 . 5 inch , is provided around the perimeter of mesh dome 118 . once assembled to form a container 10 &# 39 ;, the edges of mesh dome 120 are covered by plastic , leaving no exposed sharp protuberances . referring to fig6 container 10 &# 39 ; is assembled by placing each of the components in a stack as shown , the base tray 12 &# 39 ; having the non - woven hydrophilic mat 114 positioned to completely cover trough 54 , followed by wire mesh 116 ( sized to fit within perimeter 52 ) positioned within the tray , followed by wire mesh , load - bearing dome and plastic filter dome . a hot melt adhesive 75 , e . g . bostick # 8330 polyolefin base , is extruded around the entire inner part of perimeter 52 &# 39 ;. when the components are assembled , they are clamped in place by a standard clamp or by a machine designed to hold flanges 139 and 148 closely in contact with wire mesh 116 and tray 12 . the assembly is then placed at a temperature sufficient to melt adhesive 75 ( e . g ., 152 °- 176 ° f .) such that the adhesive passes through each of the layers . after cooling , the adhesive firmly holds the assembled components in their final position . retaining ring 22 &# 39 ; is then snap - fit into apertures 125 and 123 . wire mesh 24 &# 39 ; is placed above retaining ring 22 &# 39 ; and cover 26 &# 39 ; pushed into retaining ring 22 &# 39 ; to firmly hold wire mesh 24 &# 39 ; in place . ring 22 &# 39 ; and cover 26 &# 39 ; prevent access to the edges of wire mesh 24 &# 39 ;. in still other embodiments , an aperture may be provided in the dome elements to allow a feeding device or watering device to be attached to container 10 . in place of adhesive small staples may be provided to secure the components together . such staples to not present a hazard to animals or humans since access to the container is through the aperture in the filter dome , and because the staples are positioned within lip perimeter 52 which makes the sharp edges of the staples inaccessible . the filter dome may be formed of material of a pore size which allows about 800 ft 3 air / min / ft 2 through it ; such material will filter out air - borne contaminants in the atmosphere surrounding the container . the function of this filter is to prevent air - borne contaminants from infecting viral - antibody - free animals . generally , filtration efficiencies of approximately 50 % in the 1 thru 5 micron particle range , and 10 % in the 0 . 3 to 1 micron particle range are suitable . these efficiencies improve as the filter &# 39 ; s outer surface &# 34 ; cakes &# 34 ; with particles ( and subsequently air flow diminishes ). in another embodiment , the filter can be formed of perforated metal with the filter material laminated to its interior . this structure is further lined with a wire mesh form . such a filter dome exposes only the most durable component of the structure , the load bearing perforated metal , to abrasion hazards in transit , thus preserving the dome &# 39 ; s integrity . the wire mesh liner is reduced in material strength to act only as a barrier to prevent the animals from attacking the filter material .
a container for shipment of a laboratory - type animal , the container including a base formed of animal restraining material , disposed thereabove a load - bearing element formed of air - passing , animal restraining material . protective means cover sharp protuberances on the external surface of the base and load bearing element , and further have a smooth external surface lacking sharp protuberances . in a first embodiment , the material of the base is liquid impermeable ; in a second embodiment , the base includes liquid - passing material . also disclosed is a method for assembly of the container .