I rescued a six-year-old part Siamese female about six months ago. I started noticing she has a long ridge of fur along her spine when she is relaxed or sitting, similar to that of a (Rhodesian) Ridgeback dog. I don’t know if there is a connection, but she is also polydactyl on all four paws. I checked online, but there are no explanations for this trait. Do you have an answer for me?
— Rose, Massapequa, NY
While there is no cat breed that has a “ridge” along its spine as a breed trait, there are other cat owners who report that their felines have a narrow ridge of hair that stands up neatly along their spines while resting. I have seen this narrow ridge of hair, mostly on short-haired cats. So, while not a specific breed characteristic, it may be something genetic in how the hair grows that results in sort of “cowlick” for cats. This should not be confused with a cat raising its hackles, which is the hair around the shoulders, along the spine, and along the tail that stands up when a cat is aroused or in fear.
For my readers, polydactyly, which means “many digits,” is the congenital anomaly of having more toes than normal. Typically, cats have 18 toes, five on their front paws and four on the back paws. The record for polydactyl cats, however, is 28 total toes. As far as I know, there is no genetic connection between polydactyl cats and the gentle ridge of hair along the spine.
Cathy M. Rosenthal is a longtime animal advocate, children’s author, syndicated pet columnist, and pet expert with more than 30 years in the animal welfare field. Send your pet questions, stories and tips to firstname.lastname@example.org. Please include your name, city, and state. You can follow her @cathymrosenthal