The smallest dog breed in the world, the Chihuahua, captured our attention and hearts in the recent south of the border fast-food commercials. As you can imagine, these adorable commercials led to and increase in puppy sales and an overall increase in popularity of the Chihuahua breed.

Not only is the Chihuahua the smallest breed known to man, it is also the oldest breed of the American continent. This tiny breed, probably originated in China, but was later brought to Mexican state of Chihuahua for which it was named. It was from this state that most of the world learned about and obtained the Chihuahua breed. Today, the Chihuahua is as popular as ever, and it is still a favorite companion among dog lovers.

The Chihuahua's most identifiable features include its small size (the most prized dogs weigh around 2 lbs) and large, pointed ears. The Chihuahua's head is apple shaped, larger than its body, and frames huge, dark eyes. While most Chihuahuas are of the short haired variety, there is also a long-haired Chihuahua which possesses the same characteristics as its short-haired counterpart, except for the hair. The Chihuahua comes in many colors including sand, fawn, silver, chestnut, steel blue and black and tan.

Chihuahuas are extremely bright and lively. While Chihuahuas are very loving and affectionate toward their owner, they tend to be a little jealous of other people and can also be aggressive toward other dogs. Proper socialization can minimize these personality traits. Overall, Chihuahuas are very intelligent, energetic, and loving companions, but they can be a bit stubborn and loud at times.

Because of its small size, Chihuahuas do very well in smaller homes such as apartments. They have a tendency to be sensitive to cold so most owners paper train this breed to protect it from extreme temperatures and weather conditions. That does not mean that Chihuahuas do not enjoy the outdoors. They love exercise, but might appreciate a sweater on cool days.

The Chihuahua can be one of the simplest breeds to care for and groom. All it takes is an occasional brushing, maybe a damp cloth here and there, and you're done. You should only bathe these dogs once a month.

Chihuahuas are susceptible to several health problems including colds, stress, corneal dryness, secondary glaucoma and gum problems. The Chihuahua's delicate bones also make it susceptible to bone fractures and other accidents. Some Chihuahuas are born with an unclosed section of skull much like that of a human newborn. Sometimes these "soft spots" can remain open throughout the dog's life making them vulnerable to head injury.

Do not let the Chihuahua's small size fool you. This breed is very hardy, robust and energetic and makes an ideal, loving companion. The ease and economical care of the Chihuahua also makes it a great choice. Perhaps these are the reasons, and not the cute commercials, that makes the Chihuahua such a popular breed.