Before we can discuss issues and concerns that often arise with Chihuahua's coats, we must first explain the two different types of Chihuahuas. The first is smooth coat (or short coat). and the second is long coat. From there, you will find minor differences in the amount of fur, but everything else is generally the same.
Hair Loss and Bald Spots
The most common issue regarding the Chihuahua's coat is thinning or bald spots. Oftentimes, this will cause Chihuahua owners to rush their Chi to the vet with concerns of serious medical issues, when it could actually be a part of the normal growth process of your dog.
All dogs go through a stage of hair loss as they grow into their adult coat. This normally happened when they are 5 or 6 months old but it can occur any time within their first year. Just like a human going through puberty, this is also when your Chihuahua has pretty much finished growing and are going through major hormonal changes, part of which starts the adult hair growth. This is a necessary part of your Chi's life. During this stage, the hair loss may appear as small patches or an all-over thinning. Either way, there is no reason to panic unless you see pimples, red irritations or a rash.
The hair loss may be patchy and in different areas of the body. Common places are just around the eyes, over the dog's back or mainly on their legs. There is no pattern for this loss of fur; it is a natural part of the Chihuahua growing up. By the time your smooth coat Chihuahua has reached 1 year old, they will most likely have their full adult coat. It can take up to three years for long coat Chihuahuas to a have their full adult coat.
Medical Reasons For Hair Loss
If your Chihuahua is experiencing hair loss that does not fit into the reasons above, you must bring your Chi to the veterinarian. Demodicosis (Red Mange/Demodex) is a rather common disease is caused by a microscopic mite. These mites are part of the normal flora of the skin on all dog, and are present in small numbers, so the disease is not contagious. In predisposed dogs the mites increase in number causing clinical disease. There are different forms of this disease:
This form usually occurs in dogs younger than one year of age. Affected dogs are usually healthy and have developed demodicosis as the result of a temporary illness or a stressful event. The first sign of localized mange might be thinning of the hair around the eyelids, lips, mouth and the front legs. Prognosis is usually very good, and most dogs (90 %) will recover spontaneously without medical treatment. About 10% usually will become generalized.
Generalized demodicosis can begin as a localized case or can present itself as an acute illness. It is frequently categorized according to the age of the dog during the initial onset . The main distinction between the two types is the result of differences in predisposing factors and prognosis.
Juvenile-onset generalized demodicosis has a more favorable prognosis. Most of them will "self cure" as their immune system matures, somewhere between eight months and three years.
Adult-onset generalized demodicosis has a more guarded prognosis. These animals develop demodicosis as a consequence of another illness or immunosuppressive therapy. They do not have a genetic predilection for demodicosis. Conditions associated with adult onset demodicosis include cancer, endocrine disease, metabolic disease or steroid therapy. Prognosis depends on the underlying disease.
Please note that often times, normal puppy coat issue in Chihuahuas have been misdiagnosed as Demodicosis. This misdiagnosis seems to be more common in Chihuahuas with a blue, chocolate or black solid coat color. Be sure to get a second opinion before you begin the prescribed Demodex treatments. They are lengthy and expensive and could very well be avoided with a proper diagnosis.