Lord Ganesha And Dinka

In ancient times, when agriculture was the primary mode of sustenance, rodents were one of the biggest obstacles to prosperity. Destroying crops, eating stored grains are all done by rodents. Lord Ganesha's having a mouse/rat as his vehicle, is symbolically shown to have conquered this pest, thus staying true to his name and work as the destroyer of obstacles!

Also, Lord Ganesha was able to reach all the corners of the world and do his duty as the destroyer of obstacles. Because his vehicle is a mouse and mice/rats can slither through tiny holes and narrow pathways.

Dinka the mouse, the vehicle of Ganesha, represents speed and sharpness. Seated on Dinka the rat (Mushika), Lord Ganesh crushes baseless thoughts, which multiply like rats in the dark!

While Lord Ganesha was still a child, a giant mouse began to terrorize all his friends. Lord Ganesha trapped him with his lasso and made him his mount. Mushika was originally a Gandharva or celestial musician. After absentmindedly walking over the feet of a rishi (sage) named Vamadeva, Mushika was cursed and transformed into a mouse. However, after the rishi recovered his temper, he promised Mushika that one day, the gods themselves would bow down before him. The prophecy was fulfilled when the mouse became the vahana of Lord Ganesha!