This image is a modified (very modified - it started as two silver gerbils!) version of one which comes from the Art Today commercial clipart website, and is © 2000-present www.arttoday.com.

Art Today lists the source as GC 14 : Pets 01 (presumably a directory on a clipart CD - GC stands for "GraphicCorp"), published by Hemera Technologies. The artist is not given.