Transcript Chapter 1: Animal Agriculture

Chapter 20: Nutritional Application of
Vitamins to Human and Animal
Health
• Chapter overview:
– Chapter 20 presents the impacts of vitamins on
animal health:
• identification and sources of the vitamins
• functions of the vitamins
• impacts of vitamin deficiencies
Historical Perspective:
• Funk (1912) - introduced the term vitamine,
meaning “vital amine”
• Later the word vitamin was adopted, also
referring to the latin term vita for “life”
Vitamin Definition:
• Organic compounds essential for normal
growth and maintenance of life
– Required only in minute amounts
– Do not contribute energy, but some are critical to
metabolism of energy
– Some are metabolic, but not dietary, essentials
due to synthesis in the body
– Although some are chemically similar to each
other, there is no common chemistry of vitamins
Vitamin Nomenclature:
• Vitamins were originally categorized as:
– Fat soluble: extractable with lipid solvents
• vitamins A, D, E, K
– Water soluble: extractable in water solution
• vitamin C and the B-complex group
Vitamin A:
• Functions - regeneration of visual purple,
essential for normal epithelial tissue
• Deficiency symptoms - night blindness,
keratinization of epithelium, xeropthalmia
• Major sources - yellow corn, alfalfa, liver,
fish liver oils
• Precursor - carotene
Vitamin D:
• Functions - calcium and phosphorus
absorption and metabolism
• Deficiency symptoms - rickets,
osteomalacia, decreased egg laying
• Major sources - cured hay, fish liver oils,
irradiated yeast, milk fat, egg yolk
Vitamin E:
• Functions - antioxidant, normal
reproduction and hatchability
• Deficiency symptoms - infertility in some
species, skeletal muscular dystrophy,
exudative diathesis, encephalomalacia, liver
necrosis
• Major sources - germ of cereal grains, egg
yolk, oilseed oil, alfalfa
Vitamin K:
• Functions - prothrombin formation for
normal blood clotting
• Deficiency symptoms - hemorrhages in
various tissues
• Major sources - green, leafy plants; liver;
egg yolk; fish meal
Vitamin C (ascorbic acid):
• Functions - formation and maintenance of
intercellular material
• Deficiency symptoms - scurvy, bleeding
gums, anemia
• Major sources - citrus fruits; tomatoes;
green, leafy vegetables
• Note - generally not a dietary requirement
for domestic animals
Thiamine (B1):
• Functions - essential in carbohydrate
metabolism and energy transfer
• Deficiency symptoms - lack of appetite,
beriberi in humans, polyneuritis in birds,
reproductive failure in horses
• Major sources - milk products, brewer’s
yeast, cereals and their byproducts, liver
Riboflavin (B2):
• Functions - energy transfer, protein
metabolism
• Deficiency symptoms - lesions of skin, eye,
and nervous system; depressed appetite;
curly toe paralysis in chickens
• Major sources - milk, cheese, liver, kidney,
eggs, fish, green forages, oil meals
Pantothenic Acid:
• Functions - metabolic reactions as a
component of coenzyme A
• Deficiency symptoms - retarded growth,
skin lesions and depigmentation, goosestepping in pigs
• Major sources - cereal grains and their
byproducts, liver, egg yolk, milk, alfalfa
Nicotinic Acid (niacin):
• Functions - energy transfer
• Deficiency symptoms - pellagra (black
tongue), dermatitis, diarrhea, dementia, loss
of appetite and weight
• Major sources - milk, meat, eggs, green
vegetables, peanut butter, animal and fish
byproducts
• Note - can be partially spared by tryptophan
Pyridoxine (B6):
• Functions - protein metabolism
• Deficiency symptoms - dermatitis in pigs
and poultry, anemia in puppies and pigs
• Major sources - yeast, liver, meat, egg
yolk, milk, cereal grains, vegetables
Biotin:
• Functions - fat synthesis, deamination of
amino acids
• Deficiency symptoms - dermatitis, loss of
hair, nervous system disturbances, perosis
in chicks
• Major sources - whole grains, milk, yeast,
organ meats
Folic Acid:
• Functions - synthesis of purines and certain
methyl groups, erythropoiesis
• Deficiency symptoms - retarded growth,
anemia, poor feathering
• Major sources - green, leafy vegetables;
organ meats; cereals; soybeans; animal
byproducts
Cyanocobalamin (B12):
• Functions - carbohydrate and fat
metabolism, nucleic acid synthesis
• Deficiency symptoms - retarded growth,
low hatchability of eggs, uncoordinated
gait, anemia in humans
• Major sources - milk, meat and animal
byproducts, fish meal
Choline:
• Functions - maintenance of cell structure,
fat metabolism in liver, transmission of
nerve impulses
• Deficiency symptoms - fatty liver, renal
tubule degeneration, enlarged spleen,
kidney hemorrhage
• Major sources - milk, meat eggs, fish, fats
Related: Inositol
• Functions - lipotropic action in rat diets in
which other vitamins are deficient
• Deficiency symptoms - alopecia
• Major sources - phytin in plant products
Related: Para-aminobenzoic Acid
• Functions - growth stimulant in chicks;
anti-gray hair factor in rodents
• Deficiency symptoms - graying hair in
animals other than humans
• Major sources - a synthetic product
Vitamin Expression:
• Vitamin potency is expressed in two ways:
– Activity: International Units (IU) are the units
of expression, defined as the activity created
(example: growth) by a particular amount of a
vitamin. Example: 0.3 micrograms of
crystalline vitamin A alcohol = 1 IU
– Weight: most B-complex vitamins are reported
in supplements by weight. Example: niacin
reported as 5mg/lb of a feedstuff
Vitamin Assays:
• Biological assay- feeding known amounts
of vitamins to vitamin-depleted animals and
assessing performance
• Microbiological assay - using microbes as
test subjects in a biological assay method
• Chemical assay - determination of
concentration based upon analysis for
specific chemical characteristics