Chihuahua rat terrier mixes are generally more mild-mannered and energetic than a purebred Chihuahua. Although Chihuahuas can sometimes be aggressive in nature, breeding one with a rat terrier will generally produce a more submissive dog.
A Chihuahua rat terrier mix is often called a "Rat-Cha." Rat-Chas typically have the best of both breeds demonstrated in their personalities. Rat terriers are as energetic as any terrier and require a certain amount of patience to train. Chihuahuas are intelligent but can be stubborn and, at times, aggressive when not properly socialized.
A Rat-Cha needs plenty of exercise to keep it mentally and physically stimulated. Failure to allow the dog to release energy can result in destructive behavior.