Assistant Laboratory Animal Technician (ALAT) Practice Exam

Which of the following is NOT a method to identify mice?

1. Ear notching

2. Numbered ear tags

3. Colored fur

4. Whisker length measurement

The correct answer is: Whisker length measurement

Measuring whisker length is not a recognized or practical method for identifying individual mice. Identification methods typically rely on permanent or easily recognizable physical markers that can be consistently checked and documented. Ear notching and numbered ear tags are both standard techniques used in laboratory settings to provide a unique identifier for each animal. Ear notches involve making small cuts in the ear, which can be used to indicate specific numbers or codes. Numbered ear tags are attached to the ears and feature a number that can be easily read. Colored fur, while it may provide some level of identification based on breed or genetic lines, does not provide a unique identifier for individual mice. Fur color can vary widely even within the same species or strain, making it unreliable for consistent identification. In conclusion, measuring whisker length does not offer a reliable or feasible means of identifying mice in a laboratory setting, compared to the more standardized methods listed above.