Using Winamp with VirtualMIDISynth (three different sf2 soundfonts), I get a bird chirp on the first one, and dog bark on the second.
Using MIDI Player (based on Yamaha S-YXG50) I get two different dog barks, one from each file.
My instrument editor shows the first as Bird Tweet (MSB 121, LSB 1, defaults to MSB 0 because there is nothing listed in MSB 121) and the second as Dog (percussion kit 56 SFX Kit).
I have seen that with some hardware devices, "The MSB Value of GM2 for Voice is 121 and Drum is 120".