The Classic Comprehensive Handbook of Cat Care
DIGESTIVE SYSTEM
(GASTROINTESTINAL SYSTEM)
The digestive system consists of the digestive tube (mouth, pharynx, esophagus, stomach, small and large intestines, and anus) and the associated salivary glands, liver, gallbladder, and pancreas. Few of the foodstuffs necessary for growth, life, and work enter the body in a form that can be absorbed directly by the intestines and put straight to use by the body. Therefore it is the digestive system’s function to convert foodstuffs to absorbable nutrients, using both mechanical and chemical means.
Anatomically you will be primarily concerned with the beginning and the end of the digestive tract—the mouth and the anus. The locations of the other structures are indicated on the drawing of internal anatomy. With practice you may become quite familiar with the shape and feel of some of the internal organs because most cats are small enough and have relaxed enough abdomens to make palpation easy. Feel gently and carefully; too firm or rough an examination can cause injury to your cat. With your cat standing, feel for the liver and stomach by running your fingers down the edges of the ribs bordering the abdomen. You may feel the firm, sharp edge of a normal liver most easily along the rib edge on the right side.
Round liver edges or a liver that extends for some distance beyond the rib may be abnormal. When full, your cat’s stomach will be felt as a doughy or lumpy mass against the left side of the abdomen near the rib. You will also encounter the spleen on the left side. Feel your cat’s intestines by grasping the abdomen between the thumb and fingers of one hand. Reach up along each side of the abdomen, bring your thumb and fingers toward one another, then move them downward toward the umbilicus. The intestines will slip through your fingers like wet noodles. If you reach high up in the posterior (towards the tail) part of the abdomen you may be able to feel your cat’s colon full of stool. It will feel firm and somewhat sausage-shaped.
If you become familiar with the shape and feel of a normal stool in your cat’s colon, it may help you in the diagnosis of diarrhea or constipation. As you perform your examination of the digestive system, you are likely to encounter the kidneys and bladder. For information about these organs turn.
MOUTH
Most cats are reluctant to have their mouths examined, especially the first time. Don’t give up if your cat objects and tries to squirm away as you start your examination. Make your intentions clear and proceed with an air of confidence. If you are hesitant in your motions most cats will be quick to take advantage of the situation. Begin the examination by lifting each upper lip individually with the cat’s jaws closed. Use one hand to steady your cat’s head, if necessary, while examining with the other. This allows you to examine the buccal (outer) surfaces of the teeth and gums.
HEALTHY GUMS
SEVERE GUM DISEASE
Healthy gums feel firm and have edges so closely applied to the teeth that they look as if they are actually attached to the teeth. Gums fill the upper part of the spaces between the teeth, forming a “V” (an inverted “V” with the lower teeth) you can see between each front tooth and its neighbors. In unpigmented areas healthy gums are pink. Very pale pink or white gums, yellowish gums, red gums, or a red line along the tooth edge of pink gums is abnormal. Many normal cats have black-spotted gums, some with so much pigment that it is difficult to find a pink area to examine.
Cats’ teeth are designed for grasping, tearing, and shredding. They are typical of an animal designed by nature to eat a carnivorous diet. In a normal mouth, the upper front teeth (incisors) just overlap the lower ones. An excessive overlap (overbite) is abnormal, as is a mouth structure in which the lower front teeth extend beyond the upper ones (underbite). A mild overbite or underbite doesn’t seem to cause functional problems. However, cats bred for short faces such as Persians may have extreme underbites which are functionally unsound and are related to health problems. Be sure to check your cat’s bite and the surface of each tooth.
Abnormal tooth placement in young cats can affect jaw development and the later placement of adult teeth, so any problems you find should be immediately brought to your veterinarian’s attention. The surfaces of the teeth are white in young cats and get yellower as the cat ages. A fingernail scraped along tooth surfaces should pick up little debris. Try it. Mushy white stuff that may scrape off is called plaque, a combination of saliva, bacteria, their by-products, and food debris. This can be removed easily by “brushing” your cat’s teeth. Hard white, yellow, or brown material is tartar o r calculus (mineralized plaque) and must usually be removed by your veterinarian.
Teeth are categorized into four types: incisors (I), canines or cuspids (C), premolars (P), and molars (M). Veterinarians use a formula to indicate the number and placement of each kind of tooth in the mouth. The letter indicates the kind of tooth; the numbers placed next to the letter indicate how many of that particular kind of tooth are present in the upper and lower jaw of one half of the mouth. The average kitten has twenty-six deciduous teeth (baby teeth) arranged in the following manner. Starting at the middle of the front teeth (incisors)
A kitten has no molars. Therefore the emergence of these baby teeth and their replacement by permanent ones is a convenient way to estimate the age of a young cat (see table).
The average adult cat has thirty permanent teeth:
It is not unusual to find cats with fewer teeth than this “standard” number. Many cats never develop the full number of incisor teeth, others lose their teeth relatively early in life. Others are missing premolars or molars. If the other teeth and the gums are healthy, a few missing teeth don’t seem to cause any problems. Once a cat’s permanent teeth have erupted it is more difficult to use them as a guide to age.
Now examine the inner (lingual) surfaces of the teeth, the tongue, and the posterior part of the mouth. To open your cat’s mouth, place one hand around the upper part of his or her head and push inward on the upper lips with your fingers and thumb as if you were trying to push them between the teeth. As your cat starts to open the mouth, use the index finger of your other hand to pull open the lower jaw by pushing downward on the lower incisor teeth. Look inside. You will see the rough surface of the tongue below, the hard palate above, and the inner teeth surfaces.
An unusual sense organ, the vomeronasal organ, opens into the mouth at a small bump on the hard palate just behind the upper teeth. The rest of the organ is located in the soft tissues above the palate. When cats investigate objects with their mouths held slightly open (the Flehman or gape response) they are directing scents to this organ for evaluation.
OPENING THE MOUTH
If you move quickly you can use your finger to push the tongue to one side or the other to look under it. Using the index finger of the same hand you used to open the lower jaw, press down on the tongue. As you press down, try to move the tongue slightly forward. If you do this properly, you will mimic your doctor’s use of a tongue depressor, allowing you to see the soft palate as a continuation of the hard palate, and the palantine tonsils. Cats’ tonsils reside in a pocket (the tonsilar fossa or sinus), so they aren’t easily seen unless they are enlarged. Be very careful when examining a cat’s mouth. If there is any significant resistance withdraw your hands immediately to avoid injury.
PHARYNX
TEETH AS A GUIDE TO YOUR CAT’S AGE
| AGE | TEETH PRESENT |
|---|---|
| Birth | None |
| 2–3 | weeks Deciduous teeth coming in |
| 4–5 | weeks All deciduous teeth in except second upper premolar |
| 8 | weeks Second upper premolar in |
| 3 1/2 – 4 1/2 | months Permanent incisors coming in |
| 5 months | Permanent canines start erupting |
| 6 months | Canines fully erupted, premolar 3 and molars present |
Rarely, deciduous teeth may be retained as the permanent ones erupt. These may have to be removed by a veterinarian if they interfere with normal adult tooth placement.
After one year of age some staining and tartar accumulations are usually present on the teeth. There is no reliable way to use teeth as a guide to age, however, after a cat is mature.
LYMPH NODES
Tonsils are a type of specialized lymphoid tissue (containing many special cells called lymphocytes) similar to your lymph nodes and to lymph nodes located in other parts of your cat’s body. You can feel some lymph nodes on your cat’s head in the area located below your cat’s ear and behind the cheek where the head attaches to the neck. They are very small, firm, smooth-surfaced lumps associated with a larger similar lump.
The larger lump is one of the cat’s several salivary glands, and the only one you will be able to feel. After you feel the normal salivary gland and its associated lymph nodes and become familiar with them, try to feel the other lymph nodes indicated on the drawing. (You may need your veterinarian’s help with this; unless the nodes are enlarged they can be difficult to find the first time you try to feel them.) When you find one, learn its normal size and shape. Lymph node changes (most commonly enlargement) should alert you to have your cat examined by a veterinarian since they are often a sign of serious illness or infection.
LYMPH NODES
ANUS
The anus is the specialized terminal portion of the digestive tract through which indigestible material and waste products pass as stool. Most adult cats have one or two bowel movements daily. The number of bowel movements and the volume of stool passed, however, are dependent to a great degree on the amount of indigestible material in the diet. Cats eating dry food will tend to pass more feces than cats eating a highly digestible muscle meat, egg, and milk product diet, due to the higher fiber content of dry cat food. Normal stools are well formed and generally brown colored, although some diet ingredients may make them darker (liver) or lighter (bones). Extremely large volumes of stool, unformed, abnormally odorous stools, or unusually colored stools may indicate digestive tract disease. Be sure to try to observe your cat’s stools several times a week.
Anal sacs have been discussed with the skin. If you have not yet examined them, do it now while learning the normal appearance of your cat’s anus. You may also want to learn to take your cat’s temperature at this time since it should be a routine part of any physical examination and is usually taken rectally.