Page 354 - Small Animal Clinical Nutrition 5th Edition

Introduction to Feeding Normal Cats 363

Figure 19-2. Maxillary dentition and hard
palate of a cat (Left). Mandibular dentition and
VetBooks.ir sublingual mucosa of the same cat (Right).
These photographs demonstrate tooth anato-
my associated with a carnivorous eating
behavior. The canine teeth are slightly curved
and taper to a pointed tip suitable for grasping
and puncturing prey. The premolar and molar
teeth are conical and sharply pointed, making
them suitable for shearing and tearing flesh.
There are no grinding (flat, table) surfaces
present. (Adapted with permission from
Harvey CE, Emily PP, eds. Function, forma-
tion, and anatomy of oral structures in carni-
vores. In: Small Animal Dentistry. St. Louis,
MO: Mosby-Year Book, 1993.)

that can affect preferences throughout life. Cats accustomed to Cats also respond to high-pitched sounds, which represent the
a specific texture or type of food (i.e., moist, dry, semi-moist) range of sound frequencies emitted by typical prey (Tabor,
may refuse foods with different textures. This becomes an 1983). Finally, the highly sensitive facial whiskers and tactile
important consideration when feeding cats novel foods. hairs are thought to help cats hunt in dim light and to protect
Cats find certain flavors very attractive, which seems to their eyes.
reflect the nutritional characteristics of their natural foods. Cats
prefer the tastes of animal fat, protein hydrolysates (digests), Limbs
meat extracts and certain free amino acids abundant in muscle The retractable claws of cats are a unique adaptation to hunt-
tissue (i.e., alanine, proline, lysine, histidine and leucine). Cats ing.The sharp tips of the claws with hook-like curves and nee-
search out wild prey more often when meat is not in their diet dle features are ideal for capturing and securing prey, yet they
(Robertson, 1998). Even the feeding behaviors of cats in the are easily retracted so they do not make noise when cats stalk
wild reflect their preference for animal tissues. When ingesting prey. In contrast, the claws of dogs play only a secondary role in
prey, wild cats avoid consuming plant materials contained in capturing prey.
the entrails. African lions have been observed to first empty the
digesta from the entrails by expressing the contents with their Oral Cavity
tongues (Leyhausen, 1979). This behavior contrasts with that Cats and dogs have the same number of incisor, canine and car-
of a pack of wild dogs or wolves eating similar game. Wolves nassial teeth (i.e., the enlarged upper premolar and lower molar
often first consume the viscera of prey (Mech, 1970). teeth specialized for shearing flesh); however, cats have fewer
Herbivores are common prey; therefore, the gastrointestinal premolar and molar teeth, and they do not possess fissured
contents are generally of plant origin and have a high carbohy- crowns, which are a hallmark of omnivorous animals (Figure
drate content. Unlike dogs and other omnivores, cats are not 19-2). The jaws of cats have limited lateromedial and cranio-
attracted to the taste of sugars and are averse to flavors derived caudal movement, thereby limiting grinding ability. The scis-
from plant products (e.g., glutamic acid and medium-chain sors-like action of the carnassial teeth is ideal for delivering the
triglycerides) (MacDonald et al, 1984). Cats are also sensitive cervical bite used to transect the spinal cord and immobilize or
to bitter tastes when compared to tastes of other species kill prey. Cats lack salivary amylase used to initiate digestion of
(Carpenter, 1956). A great deal of variation in preference is dietary starches.This adaptation reflects the nutritional compo-
apparent in the cat population; owners often report that cats sition of the typical prey (i.e., low starch content).
have an appetite for cantaloupe, pumpkin, bananas or celery.
Food temperature also influences food acceptance by cats Stomach
(Figure 19-1). Cats prefer that moist foods be offered at, or Because cats evolved to eat small frequent meals, the stomach is
º
º
near, body temperature (38.5 C [101.5 F]). This preference is less important as a storage reservoir compared with the stomach
logical considering that in the wild, a cat’s food typically con- of dogs.Thus, the stomach of domestic cats is simpler than that
sists of freshly killed prey. of dogs (i.e., relatively smaller with a smaller glandular fundus).
Anatomic and Physiologic Adaptations Small and Large Intestine
Sensory Structures Intestinal length, as determined by the ratio of intestine to body
Cat eyes are well adapted to hunting. Their visual acuity is length, is markedly shorter in cats than in omnivores and her-
greater than that of dogs because of their larger optic cortex. A bivores (Table 19-3).A greater villus height in cats increases the
cat’s ears are upright, face forward and have 20 associated mus- absorptive surface area. Overall, however, the absorptive capac-
cles to provide the fine control needed to precisely locate sound. ity is estimated to be 10% less than that of dogs (Kendall et al,