Capillary Refill Time (CRT)

Checking the mucous membranes and capillary refill time is essential to evaluating the health status of any animal.

If the animal is dehydrated, the membranes will be dry and the capillary refill time will be prolonged (greater than 2-3 seconds). An animal in shock may also have an increased capillary refill time.


With a thumb or finger, apply pressure to the gums.


Once the gums under the thumb or finger have been blanched out, the thumb or finger can be removed. The blanched area should return to normal color in less than 2 seconds.