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Feeds & Ration formulation. Spring 2017. INTRODUCTION. Feeds represent the most expensive input cost for the livestock producer Expensive to maintain the animal Expensive if don't supply nutrient in adequate amounts to get good performance
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Feeds & Ration formulation Spring 2017
INTRODUCTION • Feeds represent the most expensive input cost for the livestock producer • Expensive to maintain the animal • Expensive if don't supply nutrient in adequate amounts to get good performance • Expensive if overfeed nutrients relative to the animal's requirements
INTRODUCTION • Basic nutrients • Water • Protein • Energy: fat and carbohydrates • Minerals: macro and micro • Vitamins: fat soluble and water soluble
INTRODUCTION • Important to understand most limiting nutrient concept: • Animal performance • Environment • Balance • Cost
Feeds and ration formulation involves applications of the process of nutrient utilization: • Ingestion • prehension of feed, chewing and swallowing to the initial digestive organs • Digestion • reduction of food to utilizable form; physical and chemical processing of ingested food • Absorption • food is reduced to utilizable form; transported from inside the digestive tract to the blood stream • active transport • passive diffusion • Metabolism
Biological Functions that Require Nutrients Maintenance: "the maintaining of an animal in a state of well being or good health from day to day". A maintenance ration is the feed required to adequately support an animal doing no non-vital work, making no growth, developing no fetus, storing no fat or yielding no product. As much as 100% of an animal’s ration
Maintenance • Energy for vital functions: heart, respiratory, membrane transport • energy expenditure gives off heat • Maintain body temperature • sources: heat from work of vital organs, heat from nutrient utilization, heat from work of normal activity, heat from economic work, heat from work of shivering
Maintenance • Protein for repair of tissue • there is constant breakdown or turnover of body tissue protein • excreted largely as urine • N excreted as urine during starvation equals maintenance requirement for protein • Minerals: some minerals excreted daily (not a problem) • Vitamins • Others: water, small amount of fats
Growth: increase in muscle, bone, and connective tissue (accumulation of fat is not growth) • Protein -- dry matter of muscle and connective tissue • Energy • Minerals -- especially calcium and phosphorus in young • Vitamins • Water -- free muscle tissue is about 75-80% water
Fattening • Deposition of unused energy in the form of fat • Internal fat (around abdominal organs), intermuscular, subcutaneous • Intramuscular fat • Fattening versus growth: growth is easier to deposit • muscle is mostly water • fat may actually replace water • 2.25 x's amount of energy in fat versus protein or carbohydrate • nature of the growth curve for all animals
Changes in body composition with increased age and weight of pigs age (days) weight (kg) 1 1-2 17 2-2 28 7 89 25 age (days) weight (kg) 144 60 183 90 200 110 water protein fat ash
Normal postnatal growth curves of bone, muscle, and fat.
Reproductive animals • Milk production: • nutrient requirements are in proportion to amount of milk produced • Major nutrients required are: energy, protein, Ca and P • Fetal development • ***fetal requirement for nutrients is not great • 83 lb calf (25% DM) = 22 lb of DM; which is only about 4 days of milk for the lactating animal • importance of nutrition during late gestation may be preparation for lactation (and rebreeding in cattle) • Others = wool, work, others
Nutrients from a Feed Management Perspective (Chapter 3, Kellems and Church) • Water • Water - most crucial nutrient -- most immediately required • 70% of lean body mass • Can only lose 10% of body water • Consume 3-4 times amount of water as dry matter (DM) • Consume an amount of water which is needed to maintain homeostasis (GIT, blood)
Water • Functions • transport (digesta, blood) • urine -- media to excrete nitrogenous waste • evaporative cooling • rumen microbes • Sources • drinking water • feed -- some feeds have up to 85% water • metabolic water -- oxidation of nutrients to produce water
Water • Practical Applications • water consumption is critical to maintain DM (nutrient) intake • requires management during hot and cold weather • requires management when high salt diets are fed
Energy Energy • Energy is very difficult to measure quantitatively • defined as calories -- amount of energy required to raise 1 g of water 1o C -- kilocalorie – megacalorie • Carbohydrate: C:H:O 1:2:1 C6H12O6 + 6 O26 CO2 + 6 H2O
Energy - Carbohydrates • Monosaccharides: • Glucose -- primary sugar • Fructose -- ketose, sweet, corn sweeteners • Galactose • Mannose • Arabinose • Xylose • Ribose
Energy – Carbohydrates - Polysaccharides • Nonstructural carbohydrate (NSC) or non-fiber carbohydrate (NFC): mostly starch (some simple sugars), very extensively digested and/or fermented (90+ percent), not bulky • Amylose • Amylopectin: waxy grains, probably more extensively fermented ruminally • Glycogen; animal energy storage; liver and skeletal muscle
Amylose -1, 4 linkage CH2OH CH2OH CH2OH O O O O H H O H H H H H H H O O OH H OH H OH H O O HO OH H OH H OH H OH O O O O O O O O O
6 6 CH2OH CH2OH O O 4 1 1 4 O O Structure of starch: Amylopectin, showing 1:6 branch point 6 6 6 6 CH2OH CH2OH CH2 CH2OH O O O 4 1 1 1 4 4 4 1 O O O
Energy – Carbohydrates - Polysaccharides • Structural carbohydrate = fiber: less digestible even in the ruminant, very bulky - occupies much space in the GIT • cellulose: primary carbohydrate in fiber, comprised solely of β-1,4 linked glucose, lowly digestible • hemicellulose; secondary carbohydrate in fiber; made up of glucose, xylose, arabinose, mannose, galactose • lignin -- most significant anti-nutritional factor • amorphous polyphenols • gives support to the cell wall structure • present in the "woody" plant parts • increase as plant matures
Energy – Carbohydrates – Other Polymers • Pectin -- plant cell wall cement • Cutin - waxy coat of leaf surface
Cell Content Protein Sugar Fats Starch Pectins Primary Wall Secondary Wall Hemicellulose Cell Wall NDF Lignin ADF Cellulose Diagram of a plant cell showing cell wall structure
Energy – Structural Carbohydrates • Chemical treatment - objective is to make the SC fraction of forage more digestible • Ammoniation: anhydrous, aqua or urea • Untreated straw 42% digestible • Ammoniated straw 55% digestible • Effectiveness depends on conditions during treatment • Alkaline hydrogen peroxide; oxidizes the lignin
Ruminant system of carbohydrate digestion and absorption: Polysaccharide simple sugar absorbed 6 ME or Polysaccharide simple sugar fermented to VFA absorbed ME
Ruminant system of carbohydrate digestion and absorption: • Propionic acid, most energy efficient VFA • Propionic acid increased by: • Feeding higher level of grain • Feeding ionophores • Ionophores (Rumensin and Bovatec): • Acetic acid, propionic acid, no change in total VFA • Feed:gain • Methane production, bloat
Ruminant system of carbohydrate digestion and absorption: Effect of feeding grain
Ruminant system of carbohydrate digestion and absorption: Effect of feeding grain
Energy – Lipids • fat = glycerol + fatty acids • triglyceride = glycerol + 3 fatty acids • Common fatty acid length -- C14 to C20 • very hydrogenated – energy • saturated vs. unsaturated • essential fats • linoleic: C18-2 • linolenic: C18-3 • arachidonic: C20-4
Energy – Lipids • Feed applications • fats contain 2.25 x's energy per weight as CHO's -- CHO = 4 kcal/g; fat = 9 kcal/g • increase the energy density of a ration; must be limited, usually 5-6% of ration as lipid for ruminant, 6-7% for monogastric • reduce dustiness • may increase palatability • aid absorption of vitamin A,D,E,K • may decrease absorption of Ca, Mg, Na
Energy – Lipids • Feed applications – continue • fat will reduce fiber digestion in the rumen; commonly seen in the lactating dairy cow; restrict fat to about 6 percent of the total diet DM • now have ruminally inert fats on the market to avoid lower fiber digestion; best to have a combination of fat from basal ingredients, an oil source such as whole cottonseed or full fat canola, and inert fat • fat metabolism -- ketones -- ketosis
Protein • Most expensive nutrient per weight to supply • Functions • Muscle • Enzymes • Hormones • Antibiotics • skin, hair • Amino acids are what is actually required by the animal -- building blocks of protein
Protein • Protein digestion free AA absorption transported to the cell to synthesize a new protein for use by the animal • Animal can not absorb an intact protein • 21 naturally occurring AA • 10 essential AA
Protein • Dietary Essential AA -- an amino acid required by an animal and can not be synthesized by the animal in the amounts needed; and therefore must be present and available in the diet • Arginine • Histidine • Isoleucine • Leucine • Lysine • Methionine – S-containing, Cystine may provide ½ the reqmt • Phenylalanine -- tyrosine may provide ½ of the requirement • Threonine • Tryptophan • Valine • Nonessential AA -- required by the animal but can be produced in adequate amounts • Limiting AA -- AA that is first depleted during protein synthesis
Ruminant system of protein digestion and absorption • ** dietary AA are not the same AA that are absorbed and used to synthesize animal protein
Summary -- Advantages of the ruminant system º utilize fibrous feeds º utilize NPN º B vitamin production (plus vitamin K)
Minerals Macro mineral (Ca, P, K, Na, Cl, S, Mg) Micro mineral ( Fe, Co, Cu, F, I, Mn, Mo, Se, Zn, …) • sulfates more bio-available than oxides • chelated (or proteonated) minerals (Zn, Mn, Cu, Fe, Se) may be beneficial, but are much more expensive • Most recent is FDA approval of Se-methionine • Cu, Se, Zn and Fe are now recognized to be important factors in immune function Ca, P and Mg needed in greatest abundance and most commonly supplemented
Minerals • Antagonists-an element which inhibits the absorption or transport of another element
Minerals A.Sources Ca% P% 1.Oyster shell 38 2Ground limestone 36 3.Defluorinated rock phosphate 33 18 4.Dicalcium phosphate 23.4 18.7 5.Mono-ammonium phosphate 26.9 (12.2% N) 6.Mono-sodium phosphate 22.4 7.Forages 0.3-20.15-0.4 8.Grain <0.050.3-0.4 9.Requirement 0.3 to 0.40.25 Ca:P ratio = 1.2 to 1.5:1 for growing animals and dairy 6:1 laying hens
Minerals • Phytate phosphorus • Form of P bound in phytic acid, most P in grains is in phytate form • This form of P is lowly available for monogastrics but is available for ruminants • Interest in phytase to increase utilization of P in basal ingredients - both endogenous and exogenous phytase
Minerals • Magnesium -- hypomagnesemia -- grass tetany • during cool season, low root uptake of Mg • or if dietary Ca is too high • or when high soil (forage) K • or low soil P • desire K:(Mg + Ca) < 2.3 in grazed forage • supplement with MgO, MgSO4, legumes • Symptoms include muscular twitching, collapse, convulsion
Selenium • Selenium -- Se deficient soils • FDA will now allow supplemental Se at .3 ppm; seems to be level we need for of Se-deficient soils
Copper • Copper - - deficiency of grazing animals throughout the western states; probably more associated with Mo antagonism • Want a Cu:Mo ratio in vegetation greater than 7
Thiomolybdates Mo, S (as sulfate, sulfide or S amino acids), Cu and Fe all enter the rumen via feed, soil, water or supplements. Reactions occur between Mo and S enabling the formation of thiomolybdate compounds which will readily bind Cu. In the absence of rumen-available Cu (rumen-labile Cu), thiomolybdates are able to be absorbed through the rumen wall and small intestine, allowing them to bind to Cu-containing substances, including enzymes whose activity will be reduced, thus causing clinical problems often quoted as Cu deficiency, even though it is strictly a thiomolybdate toxicity. Gould and Kendall, 2011
Copper Toxicosis • Sheep particularly sensitive to copper • 5 ppm Cu • Excessive Cu builds up in RBC, causing Heinz-body formation and methemoglobin production • Can’t bind oxygen- chocolate blood • Release of hemoglobin damages kidneys • Avoid feeding cattle mineral