Chihuahuaâ€™s A Chihuahua is a type of dog. If you see a Chihuahua shake, it is not becausethe dog is cold, it is normal. Chihuahuaâ€™s are guard dogs. The Chihuahua can be very bold with dogs much larger than themselves, so needs careful supervision. They can also be very protective of their family, being incredibly loyal and yet wary of strangers, making them a good watching dog. Mexico is considered the home of the Chihuahua. The breed we know today is smaller than their ancestors and was the first registered in the USAin 1904.