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Handling and Restraint

Regular handling of rats makes them more gentle and also reduces experimental variation that might otherwise be introduced by the stress of handling. To remove a rat from its cage or enclosure, grasp the rat at the base of the tail. Never grab the rat by the middle or end of the tail as the skin may be pulled off resulting in a severe “degloving” injury. A degloving injury refers to the separation and loss of the skin from the tail. Any animal sustaining such an injury would require euthanasia. A rat should not be suspended by the tail for extended periods of time. If a rat becomes agitated after being picked up by the tail put it down or grasp it about the body to prevent injury to the rat. Use extreme care if handling very old or obese rats by the tail as the tissues are even more apt to tear.

To bodily restrain a rat, place it on a wire cage top or other surface that it can grasp. Gently pull back on the rat at the base of the tail with one hand, and place the other hand over the back and rib cage of the rat with the thumb and forefingers placed directly behind the rat's elbows to push the legs forward so that they cross under the chin of the rat. Do not squeeze the rat's chest too tightly or it will be unable to breathe. An alternate method of restraint involves the same initial steps, but in this case the forefinger and middle finger are placed immediately behind the jaws of the rat to restrain the head.

Do not attempt to pick up or restrain wild rats by any of the aforementioned techniques as they are extremely aggressive and potentially dangerous animals. Specialized restraint devices are required for such animals.

A number of commercial restraining devices made of rigid plastic are available for working with rats and can be ordered to correspond with the size/weight of the rats that will be used during a study. Clear plastic restraint bags are also available commercially or can be made out of a freezer-type bag. These bags are in the shape of a cone and have an opening in one corner that the rat's muzzle extends through. These bags are useful for individuals working alone and injections may be administered through the bag. Animals should be restrained in such bags for short periods of time only as rats are prone to overheating. The Camilla method for administering injections uses a cloth as a simple restraining device.