Animal Nutrition All animals must eat. Whether a herbivore, carnivore, or an omnivore the ingestion of nutrition and calories must satisfy the following needs: fuel -cellular need for energy (ATP) – carbs 1st, fats 2nd, protein 3rd Organic molecules used for biosynthesis – Essential materials (vitamins and minerals) and raw material (essential amino acids) that an animal cannot make for themselves malnourishment- a diet deficient in one or more essential mineral or compound

Essential materials those amino acids that cannot be produced by an individual are considered to be essential – 9 essential AA in humans Deficiency causes kwashiorkor - protein deficiency with adequate calories meat is best source but can also obtain through food combining (whole grain +legume) minerals - inorganic cofactors – Ca (bone & muscle fx), P (nucleic acid & ATP), Mg (enzymes that split ATP), Fe (cytochromes used in cellular resp. & in Hb), I (thyroid hormones - lack gives goiter), Zn, Na, K, Cl

Vitamins vitamins -used as cofactors used in metabolic pathways – 13 are essential Fat Soluble Vitamin Used ForDeficiency Causes A component of eye pigments vision, skin, liver & bone damage Dcalcium absorption Rickets - bone deformation EantioxidantBlood clotting problems KBlood clotting factorbleeding, liver damage

Vitamins Water Soluble Used ForDeficiency Causes B1 (thiamine) Coenzyme - removing CO2 from organic compounds Beriberi - nerve disorder B2 (riboflavin)Component of coenzyme - FAD Skin lesions - cracks corner of mouth Niacin Component of coenzyme - NAD & NADP Skin & gastrointestonal lesions / nervous dissorders B6 (pyridoxine) coenzyme used in amino acid metabolism irritability, convulsions, twitching Pantothenic acidComponent of coenzyme A Fatigue, numbness, tingling of hands & feet Folic Acid coenzyme in nucleic acid and amino acid metabolism anemia, gastrointestinal problems / neural chord malformation in the fetus B12 coenzyme in nucleic acid metabolism & red blood cell maturation anemia, nervous system disorders Biotin coenzyme in the synthesis of fat, glycogen, and AAs scaly skin inflammation, neural muscular disorders C (ascorbic acid)collagen synthesis - antioxidant scurvy - degeneration of skin, teeth & vessels

Homeostatic Mechanisms Glucose regulation – excess glucose is stored in the liver and muscles in the form of glycogen stimulated by the hormone insulin when stores are full, excess glucose ingested is stored as fat – release is promoted by hormone (glucagon) secretion when caloric needs exceed ingestion of glucose, glycogen is removed from the liver 1st, muscles 2nd, and fat 3rd. deamination of protein for energy occurs after glycogen and fat stores have been eliminated – gluconeogenesis – when blood sugar is raised after feeding, appetite decreases

Homeostatic Mechanisms – homeostatic mechanism for the maintenance of weight are located in the satiety center of the brain hormones tell you when to start and stop eating – leptin - secreted by fat cells suppresses appetite as fat is stored » fat bulk decreases leptin and increases appetite – PYY - secreted by the small intestine to decrease appetite – ghrelin - secreted by the stomach at feeding times to increase appetite – insulin - secreted by the pancreas

Caloric Imbalances Undernourishment – chronic energy imbalance created by the consumption of too few calories or essential calories – usually present in times of drought, war, or where disruption of the food supply occur (poverty) – after the glycogen and fat stores are used the body begins to eat protein from muscle tissue may lead to protein imbalances in the brain some of the damage may be irreversible even after recovery has occurred

Obesity Obesity is considered an inherited condition – fat storage and the craving of fatty foods once served an evolutionary purpose as it would aid an animal in periods when food was scarce – created by the chronic over consumption of calories over consumption of carbohydrates leads to hyper storage of fat – now recognized as a global health problem by the World Health Organization (WHO) ~ 30% of Americans are severely obese (nearly doubled in the last decade) ~35% are over weight ~15% of children are obese ~300,000 deaths/year associated with obesity – obesity is associated with an increase in breast and colon cancers, diabetes, and cardiovascular disease