In mice and rats, which site is NOT typically used for blood collection?

The jugular vein is generally not used for blood collection in mice and rats primarily due to the potential complications associated with accessing this site. In small rodents, the jugular vein is much smaller and more difficult to access than in larger animals, making the procedure riskier. Attempting to obtain blood from the jugular vein may result in damage to surrounding structures or excessive bleeding, which can pose a significant risk to the animal’s health.

In contrast, the other sites mentioned—the tail vein, orbital sinus, and saphenous vein—are more commonly utilized for blood collection in these species. The tail vein is easily accessible and allows for straightforward blood sampling. The orbital sinus, while more invasive, can be employed when larger volumes of blood are necessary, often during research that requires repeated sampling. The saphenous vein is another reliable site for blood withdrawal, particularly in restraining animals in a way that minimizes stress and discomfort.

Choosing an appropriate blood collection site is crucial in laboratory settings to ensure the welfare of the animals and the integrity of the obtained samples. This context highlights why the jugular vein, while useful in larger animals, is typically avoided in mice and rats.