Pet Columns, Office of Public Engagement, College of Veterinary Medicine at the University of Illinois at Urbana-Champaign

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Why Does My Cat Do That?!


Pet Column for the week of July 30, 2001


Office of Public Engagement
2001 S. Lincoln Ave.
Urbana, Illinois 61802
Phone: 217/333-2907
Jennifer Stone
Information Specialist

Cats' enigmatic behaviors often seem inexplicable to their human companions, but cats have reasons for the things that they do!

Why does my cat make that funny face?
Have you ever seen your cat smell something very intently and then open its mouth slightly with its lips curled back? This funny face is called the Flehmen response and is seen in cats and other animals, such as horses, in response to certain smells, such as urine.
Dr. Tricia Heine, a veterinarian formerly with the University of Illinois College of Veterinary Medicine in Urbana, says, "Cats have a Flehmen response like other animals via the vomeronasal organ." This small organ located in the nasal cavity is connected by nerves to the regions of the brain controlling sexual behavior. Two small ducts lead from the vomeronasal organ to openings behind the upper front teeth (incisors). It is theorized that the Flehmen response increases the flow of the odor to the vomeronasal organ, which relays information about the smell to the brain.

What is purring?
Purring is a wonderful form of communication and mutual comfort between a mother cat and her kittens. The behavior is continued throughout life. While it is usually a sign of pleasure, a cat may purr at other times, such as when it is anxious or close to death. There has been a great deal of speculation on how purring occurs. Some have theorized that it is caused by the turbulent movement of blood through major blood vessels or by soft palate vibrations. Electromyographic tests, which measure the level of electrical activity in muscles, seem to indicate that it is actually caused by the activation of the muscles of the larynx (the structure containing the vocal cords in humans) and by partial closure of the opening of the larynx, called the glottis.

Why does my cat rub his face on everything?
Cats like to rub their chins, cheeks, and bodies on almost anything. It may feel good to them, but that is not their primary reason for doing it. Dr. Heine says, "Cats have scent glands around their mouths, chins, foreheads, and lips, so rubbing puts their scent on whatever they are rubbing against." When a cat does this to a person, it may also serve as a form of a greeting.
When cats live in a group and rub each other frequently, they are able to exchange scents and thus create a "colony scent" that provides a much faster way of identifying intruders. When a cat returns from a visit to the veterinarian, the other cats in the household may hiss and behave in an unfriendly manner, as though they do not recognize their housemate. This shows that recognition between cats has as much to do with smell as it does with visual information.

Why does my cat scratch?
The most obvious function of scratching is that it conditions and sharpens the claws. It also removes loose bits of the nail sheath that covers the nail as it grows. A less obvious function is that it serves as a visual form of identifying the area as the cat's territory. Cats also have scent glands in their paws, so scratching imparts a scent to the object, which marks it as well. This may be one of the reasons that cats continue to "scratch" even after they are declawed.

Why does my cat knead?
When my cat comes and gets on my lap, he frequently extends his claws, digging them into my thigh with an alternating rhythmic motion. My husband and I call this rather painful ritual the "happy dance," but most people know this behavior as "kneading." Kneading is a behavior that is a remnant from kittenhood. It is sometimes called "milk tread" because it is done during nursing. As the kitten suckles at the mother's teat, it extends its legs and performs this kneading motion on the area around the teat.
Dr. Heine says, "Kneading the breast promotes faster flow of milk"; therefore, this behavior is often used when milk is not flowing from the teat as fast as the animal can drink. It is speculated that as adults, the behavior is continued as a form of comfort when the animal is feeling safe and happy, so the next time your cat does the "happy dance" for you, remember that he may be associating the comfort and happiness that he gets from you with happy memories of time with his mother.