Very small chihuahuas are sometimes called "teacups." These are often the runts of the litter, which may reach a smaller adult size than the rest of their brothers and sisters. They are not a special strain or classification of chihuahua, as some breeders would like buyers to believe. Many people find them attractive and enjoyable pets; but, as with every breed, there are both pros and cons to owning this dog.
Pros: Physical Attributes
A teacup chihuahua's small size makes it perfect for apartment-dwellers. Unlike large breeds, it does not need a large yard or a spacious home. It also requires less food than other breeds. While long-haired varieties require daily grooming, its coat does not require any special care. Short-haired varieties are even simpler to care for; a damp cloth or an occasional brushing is adequate. They thrive in warm climates where some breeds become lethargic.
Cons: Physical Attributes
Their small size makes them particularly susceptible to injury from small children and other dogs. Many have a soft spot on their heads called a molera, which never hardens like the rest of the skull and leaves them vulnerable to head injuries. Because teacup chihuahuas are the smallest members of the world's smallest breed, they also have a difficult time adapting to the cold and require a sweater or a warm environment. Some may even fall prey to large raptors or other carnivores and must be watched constantly when outside. They are prone to health problems, including hypoglycemia, rheumatism, eye diseases and colds.
Teacup chihuahuas are affectionate and intensely loyal, which endears them to many dog owners. Their diminutive size does not equal diminutive courage and they make good watchdogs. They are also active and will enjoy outdoor romps, daily walks and regular play times. Their intelligence makes them easy to train.
An improperly disciplined chihuahua will believe that it is the leader of the house, despite its size. This leads to a host of negative behaviors, such as aggression and jealousy. They may become overly-protective of their owners and snap at strange people or dogs. Because they are naturally courageous, they will lunge at larger breeds and may become seriously injured. They are also strong-willed and will grow into stubborn dogs unless properly handled. Their avid barking habits and territorial instincts will annoy their owners unless they are properly broken of the habit.