There are several methods available for identifying research mice and other small animals. Temporary and permanent methods are available to the researcher.
Temporary Identification
A felt tip marker can mark the ear or tail for several days. Dyes may be used to color a patch of fur; which will generally last several weeks, however restricted to albino and light colored animals. Another method is to shave a patch of fur on the back or side of the animal.
Permanent Identification
Methods for permanently identifying rodents include ear punching, ear tagging, tattooing, and subcutaneously implanting a numerically coded transponder microchip.
Permanent Identification Methods
Ear Punching
Ear punching is commonly used for identification of rodents and involves using a special punch to either produce a small (0.5 to 2 mm) notch near the edge or to punch a hole in the middle of the ear. Always test before animal use. The cutting edge of the punch should be disinfected or the entire punch should be autoclaved
Ear Tagging
Ear tagging requires a special applicator to place an 揺arring?or metal tag with an identification number in the pinna of a mouse or rats ear. Since tags are relatively large and mouse ears develop quickly, ear tagging is primarily used on weanling and older mice. The applicator tip and ear tags should always be disinfected before use.
Tattooing
Tattooing is generally the preferred method for identifying newborn mice. The tattoo is placed on a toe or tail. When tattoos are used in weanling and older mice, they are placed on the tail, toe, or ear. During tattooing, neonatal mice are manually restrained and older mice are either sedated or placed in a restraining device. Before tattooing, disinfect the skin and the tattoo needles. Upon completion, it is important to discard used needles in an appropriate receptacle.
Subcutaneous Implanting
Subcutaneous implanting an RFID microchip is a method of permanently identifying an animal. Microchips are about the size of a grain of rice and transmit a unique alphanumeric code to the RFID. The codes are easily distinguished by the electronic reader. Since the implants are relatively large, it is not recommended for newborn mice. Implanting is ideal for identifying rodent weanlings and adults. |