No, the Chihuahua is a breed of dog.
You may be referring to Chihuahua; a breed of dog, and the name of a state in Mexico.
The Chihuahua is the smallest breed of dog.
rottweiler named rome
The Chihuahua is the smallest breed of dog.
Yes, the chihuahua is the smallest dog breed in the world.
The large dog breed is a Rottweiler.
Your question isn't quite clear but if i understood your question they are all types of dog breed (canis lupus familiaris)
Do you mean the breed of dog originating in Central America?
It is believed that the rottweiler,descended from the Molossus dog, a breed which is now extinct. See Related link...
The dog breed is capitalized as "Rottweiler".
Rottweiler