nds the bundles of fiber (protein), forming a protecting coat,
prevents the complete solvent action of the digestive fluid. Very fat
meats are not as completely digested as those moderately fat. It is also
claimed that the digestibility of the meat is influenced by the
mechanical character, as toughness of the fiber.

230. Digestibility of Vegetable Foods.--Vegetable foods vary in
digestibility with their mechanical condition and the amount of
cellulose or fiber. In some the nutrients are so embedded in cellular
tissue as to be protected from the solvent action of the digestive
fluids, and in such cases the digestibility and availability are low.
The starches and sugars are more completely digested than any other of
the nutrients of vegetables; in some instances they are from 95 to 98
per cent digestible. Some cellular tissue, but not an excess, is
desirable in a ration, as it exerts a favorable mechanical action upon
the organs of digestion, encourages peristalsis, and is an absorbent and
dilutant of the waste products formed during digestion. For example, in
the feeding of swine, it has been found that corn and cob meal often
gives better results than corn fed alone. The cob contains but little in
the way of nutrients, but it exerts a favorable mechanical action upon
digestion. Occasionally too many bulky foods are combined, containing
scant amounts of nutrients, so that the body receives insufficient
protein. This is liable to be the case in the dietary of the strict
vegetarian. Many of the vegetables possess special dietetic value, due
to the organic acids and essential oils, as cited in the chapter on
fruits and vegetables. The value of such foods cannot always be
determined from their content of digestible protein, fat, and
carbohydrates. This is particularly evident when they are omitted from
the ration, as in the case of a restricted diet consisting mainly of
animal foods. Many vegetables have low nutritive value on account of
their bulky nature and the large amount of water and cellulose which
they contain, which tends to decrease digestibility and lower the amount
of available nutrients. Because of their bulk and fermentable nature,
resulting in the formation of gases, a diet of coarse vegetables has a
tendency to cause distention and enlargement of the intestinal organs.
The carbohydrates, which are the chief constituents of vegetables, are
digested mainly in the intestines, and require special mechanical
pre