Question 1

Why is individual animal identification important in laboratory research?

Accepted Answer

Individual identification ensures accurate scientific recordkeeping and correct data collection. Distinguishing between animals guarantees that the correct subject is used for the intended experimental procedure, which is essential for maintaining research integrity and preventing errors in data attribution across multiple subjects in studies.

Question 2

What are the advantages of tail tattooing for rodent identification?

Accepted Answer

Tail tattoos are easily visualized without manually restraining the animal, making monitoring convenient. They are beneficial for experiments involving MRI imaging or animals genetically predisposed to skin conditions like ulcerative dermatitis, since the tattoo avoids problematic body areas and remains permanently visible.

Question 3

Why is toe tattooing preferred for identifying neonatal rodents?

Accepted Answer

Neonates require early permanent identification for genotyping as early as day one. Toe tattooing allows identification until pups are large enough for rodent identification ear punching and tagging. The tail is unsuitable because tailbones are not ossified and tail skin stretches as the animal grows, causing tattoo marks to become distorted and unreadable.

Question 4

What are the limitations of microchip identification in laboratory rodents?

Accepted Answer

Microchips require a 10-12 gauge needle for implantation, which is too large for mice, limiting use to adult rats. They are expensive and unsuitable for identifying large numbers of animals. Additionally, microchips cannot be used in MRI experiments, though they remain useful for identifying valuable breeder animals with unique genetics.

Question 5

When should researchers use non-toxic dyes for rodent identification?

Accepted Answer

Non-toxic dyes are ideal for short-term studies requiring identification for only a few hours or days, though dyes can remain visible for several weeks. Some researchers use markers in conjunction with other identification methods to easily spot specific animals in a group during temporary monitoring periods.

Question 6

What preparation steps are necessary before applying a tail tattoo to a rodent?

Accepted Answer

Restrain the mouse using a cup restrainer with the tail pulled taut. Clean the tail with diluted tissue cleaner on a cotton-tipped swab to remove scale and debris. Apply tissue oil with another swab to soften skin, provide lubrication, and prevent ink staining on non-tattooed areas.

Question 7

How should proper handling and restraining techniques be applied during toe tattooing procedures?

Accepted Answer

For neonates, cup the pup in your hand using gauze and position the foot between your thumb and index finger crook to expose toes. For adults, use a plastic cone or Plexiglass restrainer allowing hind foot access. Proper handling and restraining techniques ensure safe, accurate tattoo placement while minimizing animal stress.

Rodent Identification II - Assessment Quiz