© Working Dog Chihuahuas by Midwest, 2007

Coat Length in Chihuahuas
Questions and Answers about the coats of our furry friends


The length of a Chihuahua's coat is determined by two genes. The smooth coat gene is DOMINANT (indicated by capital letters), and the long coat gene is RECESSIVE (indicated by lower case letters).

If a smooth coat Chihuahua has a hidden longcoat gene, it can produce both longcoat and smooth coat puppies when bred to a longcoat male.

The dominant smooth coat gene, if present, will completely hide the recessive long coat gene. So, a dog can be a smooth coat (the dominant gene is expressed, or seen), and have a hidden long coat gene, which it can pass on to the offspring.

A longcoated Chihuahua has only recessive longcoated genes, so the breeding of two longcoats will always only produce longcoated puppies.

-Used with reprint permission from the Chihuahua Club of America to Patricia Duffer

But what does that mean?

Q: What is the difference between a smoothcoat and a longcoat Chihuahua?  What is an undercoat?  Should my Chihuahua have one?

A:  Chihuahuas come in two varieties, smooth coat and longcoat. If your Chihuahua has a smoothcoat, its hair is short and close to the body, and may or may not have an undercoat , or a protective layer of shorter fur underneath the outer or topcoat. A smooth Chihuahua that has an undercoat appears more thickly coated than one that doesn't, and usually has a furrier tail and a ruff of thicker hair around its neck. If your Chihuahua has no undercoat, its hair will be sparser. In fact, it may be so thin that it appears nearly bald on parts of her head, ears, chest, and belly. Sort of so you can see the skin on the scalp at the dome of the head but don't worry. It's not a problem. The thin coat simply means you have a smooth Chihuahua without undercoat.If your Chihuahua, on the other hand, is longcoated, it will have an undercoat and its outer coat is between an inch and an inch-and-a-half long once it is fully developed. Ears are decorated with longish hair called fringe or feathering , and your baby might even have an abundant ruff around its neck, long hair called a plume on the tail, and wispy hair on the back of each leg. Longcoat Chihuahuas also sport natural pants, long hair on the buttocks. Except for differences in the length and thickness of coat both long and short Chihuahuas should look the same because the two varieties have exactly the same conformation (body structure) underneath their coats.

Q:  What is the difference in the show ring?  Do longcoats and smooth coats show in the same category?  Is an undercoat required?

 A sparse coat disqualifies only long-coated Chihuahuas from the show ring. Short-coated dogs with thin hair are considered normal, although a thicker coat usually is more attractive.  Longcoats and smooth coat varieties of Chihuahuas show in separate categories in the Toy Group.

Q: So if I bred a longcoat to a longcoat, all puppies born will be longcoat?

A: Yes, longcoats carry the gene for longcoat and when bred together will produce longcoat puppies only.

Q: What is a medium coat?

A: There is no such thing as a medium coat, rough coat or feather coat.  These dogs may likely not have only Chihuahua in them.  There are smooth coats and longcoats, some have an undercoat (often referred to as a double coat) but the coat is either short or long, single or double coat. 

Q: Can two smooth coat dogs produce a long coat puppy?

A: Yes and no.  If both parents carry the gene (allele set) for longcoat, then they can produce both long and smoothcoated puppies in the same litter.  If only one or neither parent carries the longcoat gene, only smooth coated puppies will be born.

Q: I have a puppy that is smoothcoat and both parents are longcoat, why is that?

A:  Two longcoat parents CANNOT produce a smooth coat puppy.  However, it IS possible for two or more different males to fertilize the same litter.  One of the parents has to be a smooth coat for you to have a smooth coated puppy, it is just genetics.

Q: Do longcoats or smooth coats shed less?

A: Chihuahuas in general shed little when fed a high quality diet.  However, smooth coats shed year round whereas longcoats only shed twice a year.  So technically longcoats.  For more information on shedding visit our SHEDDING IN CHIHUAHUAS  page on this site.

Q: I bought a longcoat puppy but now it is 6 months old and has almost lost all it's hair! What is going on?

A: Longcoats are born very similar to smooth coat puppies and in many cases you cannot tell the difference until the puppy is about 2 weeks of age.  Longcoats will then get a nice thick coat and between 4 to 7 months, it will almost totally fall out and slowly start to grow back in.  This is called blowing a puppy coat.  Their coat will continue to grow in longcoats until 24-30 months of age.  Some grow in faster than others and oftentimes males have larger, thicker coats than their female counterparts.

Q: I bought a longcoat Chihuahua and now that it's coat is growing back in after blowing the puppy coat, it appears a different color.  Is this possible?

A: Yes.  Sometimes patterns like reverse brindling do not show up until an adult coat grows in and blues are famous for changing hues as the puppy grows and matures.  So nothing is wrong but it is not only possible but not uncommon.

Q:  What colors are accepted in Chihuahuas?

A:  Any color, solid, marked, or spotted on white, take your pick — and all colors or combinations of colors and markings are acceptable in Chihuahuas, and none are considered better or worse than others.  There are two patterns in Chihuahuas, they are merle and brindle.

Q: Is there a way to know if my smoothcoat Chihuahua can produce a longcoat puppies?

A: Yes!  The name of the test you are looking for is the Coat Length Determination DNA Test (Gene Code FGF5) and it is offered by DDC Veterinary.  A simple buccal swap of your Chihuahuas cheek cells and laboratory processing can easily answer this question for you.  And the nice part is you can do it all from home!  Got to DDC Veterinary for this inherited trait testing information.  The website for DDC Veterinary is www.vetdnacenter.com

Please contact us for further coat questions and we will try to promptly help answer your questions!