Industrial designers Elan Leor and Eran Lederman made this noodle that can be used as a whistle:
This innovative pasta functions as a whistle, capable of generating two different tones from one piece – a tone from each respective end. The design is based on the extrusion technology such as the well-known Penne type, with the introduction of two supplementry operations of squashing and a cut for channeling the airflow.
Link via The Presurfer
Not only dogs, according to the description it's two tone;
so also Ska and Reggae fans.
Link in case it needs an explanation.
http://en.wikipedia.org/wiki/2_Tone