Share thisThe decision of whether or not to use disposable caging is a serious one. Here are some factors to consider.
In reality, all plastic rodent caging is disposable. It is used through one or multiple sanitation cycles and then disposed of. For this discussion, disposable caging will be defined as plastic rodent caging that is intended to be used once (one sanitation cycle) and then disposed. Disposable open shoe box cages made of polystyrene have been available from two manufacturers for a number of years. More recently cages made of polyethylene terephthalate (PET) for use in ventilated caging systems (IVC) have been introduced by two U.S. manufacturers. A third U.S. manufacturer will soon introduce PET disposable cages for use in their IVC racking system. There are a number of factors that should be considered when deciding whether or not to use disposable caging. These factors include animal welfare, specific use, cost, environmental impact (manufacturing, recycling, waste stream, etc.), labour and ergonomic considerations, storage, and sanitation/sterilisation.
ANIMAL WELFARE
It has been well documented that ventilated caging provides a superior environment for animals than does static caging1. Ventilated caging systems were designed to improve the microenvironment by providing a drier environment with low ammonia levels inside the cage. These systems provide an environment that allows for longer periods between cage changes without negatively impacting the animals. These systems provide barrier at cage level, and thus, can be used both to protect animals that are free of pathogens and to quarantine animals of unknown health status or animals know to harbor pathogens2. Because IVC systems improve the microenvironment and can reduce handling by personnel resulting from fewer cage cleaning procedures, many feel animals housed in these systems experience reduced stress and discomfort3. These factors would appear to make disposable caging of the IVC type a better choice for most applications than that of the open caging type.
SPECIFIC USE
Disposable rodent caging can be used for the same applications as non-disposable caging. However, I believe that it is especially applicable for certain specific uses. These include the housing of animals used in studies with hazardous materials (chemical, infectious, or radio-isotopes). Rodent quarantine has similar requirements to biohazard studies. In both cases, disposable cages allow for the simple bagging of the dirty cage and waste bedding followed by proper disposal, eliminating the possibility of cross-contamination occurring in the cage sanitation process. Small rodent only operations are good candidates for the use of disposable caging.
Disposable caging is handy when cage wash equipment is inoperable for an extended period. Following Tropical Storm Allison, the central animal housing facilities at Baylor College of Medicine were without functioning cage wash facilities for over a month. During this time disposable caging was used to provide clean caging for cage changes.