The hair of the Coton de Tuléar is soft and cotton-like, which may be due to a gene mutation. The texture could also have come about when the breed's ancestors mated with dogs native to the island of Madagascar.
'Tall Coton' is the name given to Cotons de Tuléar that stand taller than the regular type. They're not bigger overall—they have longer legs and a lean body. Taller Cotons are born in litters of standard-sized Cotons, but are not common. A gene mutation may be the cause of the size difference. There is no breed standard for Tall Cotons and their size disqualifies them from the show ring, but the taller versions do not have any additional health concerns and are just as affectionate.
Breeders charging more for a 'rare' Tall Coton should be avoided. The trait is likely a genetic mutation and should not be intentionally bred for.
There are two types of coat change the Coton de Tuléar is known for. First, they change from their puppy coat to an adult coat some time before one year old. Their undercoat 'blows,' or sheds, as their adult coat comes in. Expect excessive brushing during this coat change—the shedding coat means matting is more frequent, which requires extra care daily to prevent discomfort. Some Coton owners keep their pets trimmed in a puppy cut to avoid the extra brushing necessary during the Coton coat change, but show dogs must not be trimmed.
The other type of change is related to color. Though breeders prefer an all-white dog, puppies may be born with shading or color at the ears or on the face, and occasionally elsewhere. This coloring may fade—black turning grey and tan lightening or turning fully white—by two years of age. The color may also disappear during the coat change from puppy hair to adult hair. It is also possible that the coat may never change or fade. Coat color matters in the show ring—but a Coton of any color is just as delightful as a pet.
The Coton de Tuléar is considered hypoallergenic because it is a low-shedding dog with hair, rather than fur—which is less likely to cause a reaction in allergic individuals. While no dog is truly without the risk of an allergic reaction, the Coton may be an option for allergy sufferers.