Chapter 20: Nutritional Application of Vitamins to Human and Animal Health

1. 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

2. 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”

3. 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

4. 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

5. 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

6. 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

7. 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

8. 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

9. 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

10. 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

11. 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

12. Pantothenic Acid: • Functions - metabolic reactions as a component of coenzyme A • Deficiency symptoms - retarded growth, skin lesions and depigmentation, goose-stepping in pigs • Major sources - cereal grains and their byproducts, liver, egg yolk, milk, alfalfa

13. 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

14. 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

15. 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

16. 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

17. 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

18. 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

19. Related: Inositol • Functions - lipotropic action in rat diets in which other vitamins are deficient • Deficiency symptoms - alopecia • Major sources - phytin in plant products

20. 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

21. 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

22. 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