ANSC 102

• Nutrition is the science of transforming nutrients through the diet to support the development of body tissues
• Feed costs represent 60-80% of the total cost of production in most livestock operations
• Nutrition can affect a product's characteristics and thus influence consumer purchases
• Product quality, such as egg yolk color, is influenced by specific feeds containing carotenoids
• Egg yolk yellow comes from carotenoids in feeds, some of which can be transformed into vitamin A
• Corn has more carotenoids compared to a wheat-based diet
• Nutritional value of products, such as pork fat content, is important
• Food safety, for example, ensuring products are antibiotic residue-free, is crucial
• Nutrition is one of the factors affecting performance
• Major environmental factor affecting animal performance
• Profit gain is essential in animal farming as it is a business
• An effective animal nutritionist has various roles including livestock management, environmental science, economics, marketing, statistics, feed processing, engineering, biochemistry, meat science, food safety, animal behavior, and animal health
• Nutrients are classified into water, carbohydrates, proteins, lipids, vitamins, and minerals
• Energy is not considered a nutrient
• Water:

  • Major functions include nutrient digestion, transport, chemical reactions, solvent properties, waste excretion, and temperature regulation
  • Sources include drinking water, feed components, and metabolic water
• Proteins:

  • Composed of amino acids
  • Essential amino acids cannot be synthesized and must be provided in the diet
  • Some gut microbes in the rumen can synthesize amino acids
  • General rule: 100g proteins contain about 16g N
• Carbohydrates:

  • Products of photosynthesis in plants
  • Basic units are simple sugars like glucose
  • Main carbohydrates in feeds include starch (storage carbohydrates) and cellulose/hemicelluloses (structural carbohydrates)
• Lipids:

  • Substances soluble in organic solvent found in plant and animal tissues
  • Fats & oils are important lipids in animal nutrition, composed of glycerol and 3 fatty acids (triglycerides)
  • Fats generally have a higher proportion of saturated fatty acids than oils
• Minerals:

  • Macrominerals include Mg, P, Ca, Cl, Na, K, S and are components of tissue structure
  • Microminerals/Trace elements include Mn, Zn, Fe, Cu, Mo, Se, I, Co, Cr and act as activators or cofactors of enzymes
• Vitamins:

  • Organic nutrients required in small quantities in the diet
  • Essential for normal metabolism
  • Specific deficiency symptoms develop when absent/deficient in the diet
  • Generally considered dietary essential
• Deficiency symptoms develop when absent or deficient in the diet
• Niacin can be synthesized in some animals from tryptophan
• Vitamin C can be synthesized in most animals
• Vitamin D can be synthesized in animals exposed to sunlight and is a precursor of cholesterol synthesis
• Fat-soluble vitamins (A, D, E, K) are stored in fatty tissues and poorly excreted
• Water-soluble vitamins are usually in deficiency because they can be readily excreted in the urine and poorly stored in the body (except B12)
• Vitamin B12 is efficiently stored by the liver
• Feed Nutrients Functions:

  • Structural material for building and maintaining body structure
  • Source of energy for heat production, work, and/or fat deposition
  • Regulating body processes or in the formation of body-produced regulators
• Nutrient Requirements:

  • Energy requirement is a major nutritional need
  • At least 80% of total feed intake consists of sources of calories
  • Protein/amino acid requirement varies with animal species, stage of growth, and type of production
  • Typical livestock diet consists of:
  • 10-20% protein/amino acid sources
  • 80-90% energy-yielding nutrients
  • 3-5% minerals
  • <1% vitamin supplements
• Nutrient Sources:

  1. Roughages:

  • More than 18% crude fiber; generally low in energy
  • Grasses (Poaceae family) have high lignin content and lignin increases as the plant matures
  • Legumes (Fabaceae family) have high protein content and presence of ANFs (tannin, mimosine, etc.) affecting nutrient digestibility

  2. Concentrates:

  • Relatively high in digestible nutrients and low in fiber (<18%)
  • Energy Feeds:
  • Cereal grains
  • Milling by-products
  • Fats and oils
  • Tubers/Root crops
  • Protein Feeds:
  • Animal protein feeds
  • Plant protein feeds
  • Feed Supplements:
• • Amino acids
  • Vitamins
  • Minerals
• • Prevents indigestible objects from entering the stomach
  • Known as the "hardware stomach"

  3. Omasum:

  • Composes 7-8% of bovine stomach
  • Absorbs mostly water

  4. Abomasum:

  • The "true" stomach
  • Composes 7-8% of stomach in mature animals and 70% in young animals
• Classification of Animals Based on Type of Digestive System:

  A. Non-ruminants or Monogastrics:

  1. Simple-stomached animals:

  • Swine

  2. Modified simple-stomached animals:

  • Poultry species

  3. Herbivorous monogastrics:

  • Horse, rabbit

  B. Ruminants or Compound-stomached animals:

  • Cattle, carabao, sheep, goat

  1. Rumen:

  • Composes 80% of ruminant stomach in animals and 30% in young animals
  • Fermentation vat with presence of microorganisms (bacteria, protozoa, fungi, etc.)
  • Anaerobic environment, normal temp. 39-41°C, pH 6.9 to 7.2

  2. Reticulum:

  • Composes about 5% of bovine stomach
• Carbohydrates (CHO):

  • Primary component found in livestock feeds
  • ~75% of plant dry matter
  • Only <1% in animal body
  • Occurrence in plants:
  • Cell content: storage/non-structural CHO (starch)
  • Cell walls: structural CHO (cellulose, hemicellulose)
  • Functions of Carbohydrates:
  • Source of energy
  • Building blocks for other nutrients/body substances
  • Milk carbohydrate: Blood glucose — precursor of both glucose and galactose (lactose), components of genetic
• Carbohydrates are the precursors of both glucose and galactose (lactose)
• Carbohydrates are components of genetic materials DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) that convert to ribose (pentose)
• Stored energy in the animal body is converted to fats
• Carbohydrates are present in the liver, muscle, and glycogen
• Glycogen is a temporary storage carbohydrate in animal tissues
• Carbohydrates are involved in cellular communication