Page 954 - Small Animal Clinical Nutrition 5th Edition

988 Small Animal Clinical Nutrition

VetBooks.ir Box 47-6. Natural Food Sources and
Periodontal Disease.

Early literature reported that the typical foods of wild canids and
felids had a plaque-retardant effect and that wild canids and
felids were not afflicted with the generalized form of periodontal
disease seen in domesticated pets. Pet food commercialization
is often implicated as a contributing factor to the increased
prevalence and severity of periodontal disease in domestic dogs
and cats (Box 47-3). The constituents of natural foods for wild
canids and felids probably depend on geographic location, envi-
ronmental season and individual hunting capabilities. However,
historically a natural food refers to small rodents/mammals that
would typically fall prey to wolves, coyotes, etc. Colyer specifi-
cally refers to “flesh that the animals must rend with their teeth.”
Wild canids in particular probably eat fruits and vegetables and Figure 47-5. Comparison of plaque, stain and calculus accumulation
an array of tissues including blood, intestines plus contents, in dogs fed a specialty brand moist food (Moist A), a grocery brand
muscle, cartilage, bone marrow and bones. moist food (Moist B) and a grocery brand dry food. There is no signif-
Despite these assertions, there are no published data that icant difference in substrate accumulation among dogs fed the three
compare controlled populations of domestic dogs or cats con- foods. Moist foods do not always promote increased plaque and cal-
suming natural food sources with those consuming a commer- culus formation in comparison to dry foods.
cial food. In addition, even if it were possible to make such com-
parisons, confounding variables might include dramatic changes
in food form (moist, semi-moist, dry and evolving pet owner have demonstrated that foods possessing an appropriate combi-
preferences) through development of commercial pet foods, nation of shape, size and mechanical structure provide signifi-
specific nutrient variation and selective breeding, which has cant plaque, calculus and stain control in dogs and cats (Logan,
resulted in dramatic differences in body size and head types of 1996, 1996a; Boyce, 1992; Jensen et al, 1995; Logan et al, 1995;
dogs and cats.
Reports exist about the oral condition of small populations of Finney, 1996). A six-month study investigating the effects of
dogs and cats consuming natural foods. One study involved 67 food on plaque accumulation and gingival inflammation in 40
English foxhounds, one to nine years of age that were routinely adult mongrel dogs reported that dogs fed the test food had 39%
fed raw carcasses consisting of the bony skeleton, muscle and less plaque accumulation and 36% less gingival inflammation
associated tissues. Oral examinations revealed that all dogs had than dogs fed the control food (Figure 47-7).These studies used
varying signs of periodontal disease as well as a high prevalence a clean-tooth model in which plaque, calculus and stain were
of tooth fractures. Another study examined 45 small feral cats evaluated at a specified time following a dental prophylaxis.
from an Australian national park and reported conditions includ- One study reported that feeding a food with appropriate
ing calculus deposits, periodontal disease, fractured teeth, attri- physical characteristics to beagles with existing plaque, calculus
tion and tooth resorption. Examination of gastrointestinal con- and gingivitis resulted in a significant decrease in mean plaque
tents of these cats revealed the presence of natural food and calculus indices after two weeks and in the gingival index
sources including small mammals, birds, lizards and insects.
These findings cast skepticism on the long-held view that a nat- after six weeks (Figure 47-8). Beagles eating the control food
ural food source prevents development of oral disease, particu- had a significant increase in plaque and calculus accumulation
larly periodontal disease, in dogs and cats. Box 47-8 describes and no change in gingival inflammation over the 16-week test
the role of chew toys in periodontal health. period (Finney et al, 1996).
Fiber-containing foods have long been viewed as “nature’s
The Bibliography for Box 47-6 can be found at toothbrush.” Investigators have theorized that fibrous foods: 1)
www.markmorris.org. exercise the gums, 2) promote gingival keratinization and 3)
clean the teeth. Fiber in foods, especially as it relates to texture,
has been shown to affect plaque and calculus accumulation and
little dental cleansing. As a tooth penetrates a kibble or treat gingival health in dogs and cats (Watson, 1994; Boyce and
the initial contact causes the food to shatter and crumble with Logan, 1994; Logan, 1996). Certain types of fiber combined
contact only at the coronal tip of the tooth surface (Figure 47- with specific manufacturing processes can affect a food’s tex-
6). To provide effective mechanical cleansing, a food should ture. Fiber characteristics that maximize tooth contact time
promote chewing and maximize contact with the tooth sur- (e.g., orientation within the kibble matrix), combined with a
face (Figure 47-6). size and shape that promote chewing, are critical to obtaining a
Foods with enhanced textural characteristics promote oral dental benefit. A typical dry food does not possess the mechan-
health. Several maintenance pet foods are available that provide ical characteristics for adequate dental cleansing. Simply en-
clinically significant oral cleansing compared with regular com- larging the kibble or varying the shape of the product is like-
mercial dry or moist foods and/or snacks. Numerous studies wise inadequate. In the absence of effective plaque control