柴犬

Etymology
.

Noun

 * 1) Shiba Inu

Etymology 1
Compound of,  possibly in reference to the dog's small stature and ability to pursue prey even through overgrown terrain.

Noun

 * 1) a Shiba Inu

Etymology 2
Compound of, using the on'yomi of ken for the second character.

Noun

 * 1) a Shiba Inu

Usage notes
The shiba inu reading appears to be more common in general usage.

Usage of the different readings might reflect regional differences. The shiba ken reading appears to have more prevalence in, for instance.