Transcript Diet and Nutrition of Cats and Dogs

Diet and Nutrition
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Complete diets
Cost
Allergies
Quality ingredients
Weight management
Special needs
Nutrients
• Plants are composed
primarily of fibrous
carbohydrates, and
store most of their
reserve food as starch
• Animals consist mostly
of proteins and lipids,
and store most of their
reserve food as as fat
Water
• Animals have three sources
of water:
– Water which they drink
– Water ingested as a
component of food and other
drinks
– Metabolic water, which is
derived from the digestive
breakdown of carbohydrates,
fats, and proteins.
• Metabolic water is the
primary source of water for
animals during hibernation
Water
• Water has many functions:
– Transports nutrients
throughout the body
– Used in most biochemical
reactions
– Helps regulate body
temperature
– Elimination of body wastes
– Constituent of the synovial
fluid that lubricates joints
• Animals will die more
rapidly from lack of water
than from lack of any other
dietary substance
Carbohydrates
• Carbohydrates are the major
energy storage and structural
constituent of plants
• They include:
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Monosaccharides
Disaccharides
Oligosaccharides
Polysaccharides
• Plant polysaccharides, starch
and fiber are the principal
carbohydrate constituents in
manufactured petfoods
Carbohydrates
• Major source of energy
utilized for many body
functions
• Essential for the
metabolism of other
nutrients
Carbohydrates
• Monosaccharides
– Simple sugars that can be absorbed directly from the
gastrointestinal tract include:
• Glucose
– Principal carbohydrate used for energy
– End-product of starch
• Fructose
– Found in honey, fruits, and some vegetables
• Galactose
– Derived from the digestion of lactose
Carbohydrates
• Disaccharides
– Two monosaccharide
units linked together
• Sucrose (table sugar)
– Composed of one
molecule of glucose
linked with one of
fructose
• Lactose (milk sugar)
– Composed of a
molecule of glucose
linked to a molecule of
galactose
Carbohydrates
• Disaccharides
– Digestion requires the
enzymes sucrase and
lactase
• Young animals have high
levels of lactase and low
levels of sucrase and thus
should not be fed
formulas containing table
sugar during the first few
weeks of life
Carbohydrates
• Galactooligosaccharides
– Short chains of galactose and are found in soybeans
– Partially digested portion promotes the growth of
beneficial colonic bacteria
• Polysaccharides
– Long complex chains of monosaccharide units linked
• Primary types:
– Starch
» composed of soluble “alpha” monosaccharide
– Fiber
» composed of insoluble “beta” monosaccharide units
Fats
• Dietary fat
– Concentrated source of
energy, essential fatty
acids and Fat-soluble
vitamins
– Enhances palatability
and gives desirable
texture
Fats
• Lipids
– Oils
• High percentage of shortchain or unsaturated fatty
acids are liquid at room
temperature
– Fats
• High percentage of
saturated fatty acids and
longer-chained fatty acids
are solids at room
temperature
Fats
• Fatty acids
– Classified by size and
number of double bonds
• Saturated
– No double bonds
• Monounsaturated
– One double
• Polyunsaturated
– More than one double
bond
Fats
• Most commercial dry dog foods
for adult maintenance contain 5%
to 10% fat
• Poultry is the most common
source of fat used in dog and cat
foods, although beef and pork
lard are also used
• Corn, soybean, and safflower oils
are the most commonly used
vegetable fats in petfoods
• Fish oils and flaxseed are rich in
omega-3 fatty acids
Fats
• Dogs are more efficient
than cats in digesting fats
• Excess dietary fat may
promote obesity
• Overweight cats are more
likely to develop diabetes
mellitus, experience
lameness, have skin
disorders, and have a
shorter life expectancy
Protein
• Protein constitutes nearly
50% of the dry matter of
an animal’s body
• Composed of amino acids
attached to each other by
peptide bonds
• amino acids are
important as structural
components of body
tissues
Protein
• 10 a.a. cannot be synthesized and are dietary
essentials
• (PVT TIM HALL)
– Phenylalanine
– Valine
– Threonine
– Methionine
– Arginine
– Tryptophan
– Histidine
– Isoleucine
– Leucine
– Lysine
Protein
• Taurine (not a true a.a)
– Roles in feline reproduction, bile acid conjugation,
retinal function (vision), and normal function of
the myocardium
– Cats cannot synthesize taurine and require a
continual dietary source
– Present only in animal tissues
– Signs of taurine deficiency:
• central retinal degeneration (resulting in blindness)
• dilated cardiomyopathy (heart failure)
Protein
• Structural and
functional roles
proteins play in dogs
and cats include:
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Growth
Tissue and cellular repair
Enzymes
Hormones
Antibodies
Carrier proteins
Sources of energy
Protein
• Symptoms of advanced
protein deficiency
include:
– Decreased food intake
– Growth inhibition and/or
weight loss
– Lowered levels of blood
proteins
– Muscular wasting
– Emaciation
– Death
Protein
• Physiologic states
requiring protein intake
above that needed for
maintenance
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Growth
Pregnancy
Lactation
Geriatric Age
Protein
• Protein is the most expensive major component
of companion animal diets.
– Raw materials of animal origin not suitable for human
consumption constitutes used in formulating petfoods
– Animal meats are by-products
• Meat-packing
• Poultry-processing
• Fish-canning industries
– Important sources of high-quality protein, energy, and
minerals.
Protein
• Plant proteins have been a reliable source of
nutrients in petfoods for decades.
– Soybean meal is the most common plant protein
used in dog diets.
– Most other cereal proteins are low in the amino
acids lysine, methionine, leucine, and tryptophan.
• Animal proteins are preferred in companion
animal diets, especially those of cats