1. The Water-Soluble Vitamins B vitamins Vitamin C

2. B Vitamins Originally thought to be one vitamin 8 of them Act primarily as coenzymes in metabolic pathways Important for ATP production!!! Important for MANY additional functions.

3. B Vitamins Dietary requirement is linked closely to metabolic rate (i.e., production) Ruminant requirements met by rumen bacterial synthesis Hindgut bacterial synthesis and absorption is insufficient to meet full requirements for a horse

4. B Vitamins-Sources VARIETY of foods! Plant sources Found in fibrous portion of plants Most cereals and grain products are enriched Animal sources Liver Milk Egg Beef, pork and chicken

5. B Vitamin-Deficiency LOTS of symptoms including fatigue Specific diseases for each vitamin deficiency (e.g., beriberi, pellagra)

6. Thiamin (B 1 ) Present in tissues as thiamin pyrophosphate (TPP) TPP is an essential coenzyme for oxidative decarboxylation of alpha-keto acids pyruvate to acetyl CoA Deficiency beriberi in humans polyneuritis in birds bracken fern poisoning in ruminants and horses antithiamin activity

7. Polyneuritis

8. Riboflavin (B 2 ) Essential constituent of flavoproteins (e.g., FAD) Hydrogen carrier in glycolysis, TCA and oxidative phosphorylation Deficiency curled toe paralysis in birds

9. Curled Toe Paralysis

10. Nicotinamide (niacin) Amide derivative of nicotinic acid Can be synthesized from trytophan Essential constituent of NAD and NADP Hydrogen carrier catalyzed by dehydrogenase enzymes ATP synthesis Deficiency Pellagra in farm animals and humans Fiery inflammation of tongue, mouth and upper esophagus

11. Pyridoxine (B 6 ) Active form is pyridoxal phosphate Essential coenzyme for transamination and decarboxylation of amino acids Deficiency None in farm animals

12. Pantothenic acid Dipeptide derivative of alanine and a butyric acid derivative Essential constituent of coenzyme A Acyl transfer Deficiency None in farm animals

13. Folic acid (folacin) Tetrahydrafolic acid is active functional form Carrier of one-carbon (e.g., methyl) groups Deficiency None in farm animals

14. Focus on Folate Important for proper neural development during fetal growth. Controlled, clinical intervention trial showed decreased risk of spina bifida in women supplemented with folate “problems” with study Current recommendation

15. More on Folate May also reduce (greatly) risk for heart disease Dietary Sources Animal sources Liver Crab meat Plant sources Spinach Lentils Dried beans Fortified cereal products!

16. Biotin Coenzyme involving CO 2 transfer acetyl CoA to malonyl CoA Propionyl CoA to methylmalonyl CoA Pyruvate to oxaloacetate Deficiency Fatty liver and kidney syndrome, a fatal metabolic disorder in chicks and turkey poults Raw egg white (avidin) can block absorption

17. Cyanocobalamin (B 12 ) Active form is cyanide derivative of cobalamin Cobalt is an integral component Coenzyme for numerous reactions Methylmalonyl CoA to succinyl CoA DNA synthesis Transmethylation (methionine synthesis) Deficiency Pernicious anemia in humans (lack intrinsic factor) Wasting disease in ruminants (Co deficiency)

18. Vitamin C Discovery Sailors used to die from disease called “scurvy.” James Lind conducted first human nutrition intervention trial and found that citrus fruits prevented scurvy. Why Brits are called “limeys.”

19. Vitamin C Ascorbic acid Antioxidant Protects cells from free radicals Protects iron from oxidative damage, thus enhancing iron absorption in the gut Required for various hydroxylation reactions proline to hydroxyproline for collagen synthesis Deficiency Not in farm animals Scurvy in humans

20. Vitamin C Roles in the Body Stress (e.g., infections, smoking) Mechanism unknown, but vitamin C requirements increase during stress Common cold? Disease prevention? Cancer, heart disease: stay tuned…

21. Vitamin C Deficiency Scurvy Bleeding gums Small red spots on skin Rough skin Wounds fail to heal Weak bones and teeth Anemia and infections

22. What about vitamin supplements? Remember, most supplements that you can buy aren’t actually vitamins. Megadosing (> 500% RDA) almost never recommended No harm in “one-a-day” type Probably prudent in Those who do not eat certain types of food People with generally poor diets Don’t get lazy BECAUSE you take a supplement.