Probably works well against chihuahuas and Pekinese too.
I live in the country side of central Texas. Rattlesnakes are on my land. It would be impossible to clear my acres of them. I leave them alone unless near my house where they pose a danger to my family and pets. I reluctantly kill them and will continue to do so. My dog tells me when they are near. I then kill them, 12 gauge shotgun with #6 shot. The snake feels no pain. He or she is instantly obliterated at the head. I have no problem with killing vermin. It is just house cleaning.
Oddly I no longer shoot deer and game on my land. I just got tired of killing. I have absolutely no problems with ethical hunters. One shoots game on my land and we share the venison and turkey. It is delicious.
The turkey is not your store bought turkey. It has a gamey taste. It is excellent for stews and chilies and oddly would be great as a gumbo. You should try it.