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Ag 530– Advanced Animal Science RMHS Ag. Department Ms. Bly. Unit 2– Animal Nutrition Section 2– Livestock Feedstuffs. Objectives. Explain the functions of feed and how they supply nutrients to livestock.
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Ag 530– Advanced Animal ScienceRMHS Ag. DepartmentMs. Bly Unit 2– Animal NutritionSection 2– Livestock Feedstuffs
Objectives • Explain the functions of feed and how they supply nutrients to livestock. • Identify, compare and contrast the types of feedstuffs (roughages, concentrates, and supplements/additives). • List sources of fats, minerals, vitamins, and proteins in animal feeds/ rations. • Distinguish between good qualify and poor quality feedstuffs, and examine how processing methods improve digestibility. • Examine storage and feeding practices of feedstuffs.
Terms to Know… • Maintenance Ration • The feed mixed in the proper proportions and amounts for an animal to maintain its weight and other bodily functions • Feedstuff • A basic ingredient of a feed that would not ordinarily be fed as a feed itself. It is usually a concentrate of a particular nutrient.
Terms to Know… • Anabolism • The growth process by which tissues are built up. (Examples: maintenance of the body, growth, and tissue repair) • Catabolism • The process of breaking down tissues from the complex to the simple as in the digestive process.
Terms to Know… • Amino Acids • The basic building block of protein • They go into the formation of tissues that provide growth, especially muscles • Essential Amino Acids • Any of the amino acids that cannot be synthesized by an animal’s body and must be supplied from the animal’s diet (there are 10 of them) • Nonessential Amino Acids • Amino acid that can be synthesized by the animal’s body (there are 10 of them)
Terms to Know… • Crude Protein Content • Total amount of protein in feed (including digestible and non-digestible proteins) • calculated by analyzing the nitrogen content and multiplying that percentage by 6.25 • Digestible protein is usually 50-80 percent of the crude protein
Terms to Know… • Tankage • Dried animal residues usually freed from fats and gelatin • Monosaccharides • The simplest sugars • Examples: glucose, fructose, and galactose • Disaccharides • The more complex sugars • Usually a combination of 2 simple sugars
Terms to Know… • Glucose • A common sugar that serves as the building blocks for many complex carbohydrates • found in a low concentration in plant materials • Major energy source found in blood • Fructose • The sugar found in fruits and honey • The sweetest of all the sugars • Galactose • The sugar found in milk after the disaccharide lactose has been broken down
Terms to Know… • Sucrose • Disaccharide comprised of fructose and glucose (common table sugar) • Lactose • Disaccharide comprised of galactose and glucose
Terms to Know… • Lipids • Fats, including cholesterol • Not water soluble • Only dissolve in certain organic solvents • Serve as concentrated storage places for energy • Inorganic • not containing carbon and usually derived from nonliving sources • Examples: water, minerals
Terms to Know… • Macrominerals • Minerals that are required in relatively large amounts in an animal’s diet • There are 7; calcium, chlorine, magnesium, phosphorus, potassium, sodium and sulfur • Microminerals or Trace Minerals • Minerals that are required in very small amounts in the diet • There are 9; cobalt, copper, fluorine, iron, iodine, manganese, molybdenum, selenium, and zinc • Deficiency • a shortage of substances necessary to health
Terms to Know… • Free Choice • Feeding an animal with an unlimited supply of feed. The animal is free to eat whenever it wants. • Carotene • An orange or red pigment found in green leafy plants, especially carrots. It can be converted to Vitamin A by an animal’s body • Toxic • Poisonous • Can be caused by excessive levels of vitamins in an animals diet
What are Nutrients? • Chemical substances found in feed materials that can be used, and are necessary for the maintenance, production, and health of animals • Nutrients are needed by animals in definite amounts varying with age, function, use etc..
Economic Production of Animals • Meeting the total nutritional requirements • Knowing the nutritional requirements and the nutritional value of the feeds
How much to feed? • Depends on function of animal • Pregnant, Lactating, Working, Growing • How often to feed • Depends on stomach size & rate of metabolism • Stomach size is relevant to amount of feed fed • Mink = 4-6 times/day, Cows = 1-2 /day
Nutrients • Carbohydrates • Fats • Protein • Minerals • Vitamins • Water
Energy Feeds • Energy needed for all life processes • Deficiency: slow or stunted growth, body tissue loss, lowered production of meat, milk, eggs, fiber • Carbohydrates most important source of energy, than fats
Carbohydrates • More abundant and cheaper • Very easily digested and turned into body fat • Easier storage than fats
Proteins • Complex compounds made of amino acids • In all plant and animal cells • Nitrogen content multiplied by 6.25 tells the amount of protein • Plants make their own protein
Amino Acids • Some are created by the body, nonessential • Others can’t be made fast enough, essential • must be furnished in the feed • Poor Quality Protein Feeds: • insufficient amount of essential proteins
Source of Protein • Animal Proteins are superior for monogastrics • better balanced in essential amino acids • Milk and Eggs are abundant in essential amino acids
Essential Amino Acids • Most likely AA to be deficient are: • Lysine, Methionine, and Tryptophan • Cereal grains are low in these • Rations with high amounts of cereal grains require supplements with proteins with higher levels of these amino acids
What are Minerals? • Natural elements which regulate certain body functions • Na, Ca, P, Fe, Cu, K, Mn, Mg, Zn, Mo, Se, I, Co • Most are trace minerals
Minerals • Free choice or in ration • Supplement for deficiency only • Trace minerals in areas where soil is deficient
Functions of Minerals • Give strength to skeleton • Part of protein • Activate enzyme systems • Control fluid balance • Regulate acid-base balance • Exert effects on nerves / muscles • Engage in mineral-vitamin relation.
What are vitamins? • Compounds responsible for certain functions • Fat Soluble = A, D, E, K • Water Soluble = B, C
Why don’t cattle need as much B vitamins? • Microorganisms in the stomach of the cow make their own B vitamins • Can also make some proteins if given the right kind of Nitrogen
Water • Most vital of all nutrients • 40% of fat hog to 80% of newborn lamb • Free access to Clean, Fresh Water at all times
What is a Feedstuff? • any ingredient, or material, fed to animals for the purpose of sustaining them • most provide one or more nutrients • nonnutritive = flavor, color, palatability, adding bulk, preservatives
Feed Classifications • Roughages • Concentrates • By-product feeds • Protein Supplements • Minerals • Vitamins • Special Feeds • Additives, Implants, & Injections
What foods give energy? • Carbohydrates (starch & cellulose) & Fats • Fat = 2 1/2 times energy of CHO • Energy is major part of a feed ration • Up to 90% of a ration for a steer • Measured in Kilocalories or TDN (Total Digestible Nutrients)
What are additives? • Antibiotics: disease prevention • Coccidiostats: control parasites • Xanthophyll: makes egg yolks yellow • Hormones: increase growth • Tranquilizers: calm nerves (cattle, turkeys) • Antioxidants: prevent feed from getting rancid • Pellet Binders: keep in pellet form • Flavoring Agents: make taste better
Livestock Feeding • Roughage = high fiber, low energy • Concentrate = low fiber, high energy
Roughages • Bulky feeds low in weight per unit • Contain more than 18% crude fiber • Low in Energy • Natural feeds of ruminants • Generally low in digestibility • High in Ca, K, and trace minerals • Higher in fat-soluble vitamins • Protein varies • Quality varies; (Note: A high quality hay has less than 30% fiber and more than 15% protein.)
Roughages • Pastures • Hay • varies more than any other feed • harvest at optimum time • cure properly 20% moisture or less • Crop Residues • left in field after harvest • straw, corn stalks, etc. • fed to right class of animal & supplement
Roughages • Silage = fermented forage plants • mostly corn or sorghum • 2 1/2 to 3# silage replaces 1# hay due to lower dry matter content of silage • Haylage = low moisture silage • grass or legume wilted to 40-60% moisture before ensiling • more dry matter & feed value
Roughage • Green Chop (silage) • fresh plants cut and chopped in the field, transported and fed to animals in confinement • 50% more feed value • extra equipment required • harvest every day
Roughage • Other Roughages • cottonseed hulls • corncobs • sawdust • beet tops • root crops • oat hulls • peanut hay • newspapers
Concentrates • Feeds high in energy an low in fiber (under 18%) • Availability and Price • Need to substitute concentrates for each other as price changes • Corn, Sorghum, barley, rye, oats, wheat, triticale
By-Product Feeds • Feeds left over from animal and plant processing or industrial manufacturing • Roughage and Concentrate
By-Product Feeds • Milling by-products from: • cereal grains • oilseeds • root crops • dried beet pulp and tops • distillery and brewing • unused bakery products • fruits and nuts
How is a ration balanced? • Pearson square: balance a ration using any two ingredients for one nutrient • How much Soybean Meal (44% Protein) should be mixed with Barley (13% Protein) to get a mixture that is 16% protein?
Pearson Square • Soybean Meal = 3 parts • Barley = 28 parts • Total Parts = 31 • Soybean Meal = 3/31 or 10% • Barley = 28/31 or 90% • If mixing a ton (2000#) SBM = 200#, Barley = 1800#
Feed Processing: Mechanical • Dehulling: removing the outer coat of grains, nuts, fruits (hulls are high in fiber, low in digest. for monogastrics) • Extruding: pressed, pushed or protruded through constrictions under pressure (disrupts starch granules)
Feed Processing: Mechanical • Grinding: reduced in size by impact or shearing (cheapest, most common) • Rolling: compressed into flat particles by rollers • Dry: breaks hull or seed coat • Steam: keeps more intact
Feed Processing: Heat Treatments • Heat can damage some nutrients • Not done for monogastrics • Dry Heat • Micronizing: microwave (sorghum) • Popping: rapid heat (sorghum) • Roasting: oven (corn & soybeans)
Feed Processing: Heat Treatments • Moist Heat • Cooking: potatoes, beans, soybeans for pigs • Exploding: swelling caused by steaming under pressure (resembles puffed cereal)
Feed Processing: Heat Treatments • Flaking: steam rolling, longer steaming period • Pelleting: compacting and forcing through a die • mechanized feeding • eliminate dust • feed on ground