Nutrient Analysis Nutrient Analysis Nutrient Analysis Nutrient

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					                                                             Nutrient Analysis
                                                       • Animals require certain chemicals from
                                                         their diet in order to function
                                                       • Other food chemicals may be negative
                                                       • Nutritionists must be able to measure
                                                         these chemicals to know feed’s value
                                                       • Enables ecologists to condense the huge
                                                         array of foods an animal may eat into a
                                                         manageable set of chemicals important to
                                                         the animal

     Nutrient Analysis                                       Nutrient Analysis
                                                       • Water
                                                       • Important to measure because:
                                                          – Preformed water
       • Fig. 1 from page 308 of
                                                          – Water may dilute other nutrients (e.g. cactus)
         Wildlife Techniques Manual
                                                          – Express food content on dry matter basis
                                                       • Determine moisture by drying at 100 C for
                                                         24 hrs
                                                       • Samples may contain volatile chemicals
                                                          – Can dry at a lower temperature (e.g. 60 C)
                                                          – Freeze dry sample (lyophilize)

     Nutrient Analysis                                       Nutrient Analysis
• Next division is inorganic vs. organic               • Organic compounds
• Minerals are inorganic component                     • Carbohydrates (CHOs)- Sugars and polymers
  – Important in animal’s metabolism                   • Non-structural – Energy storage for plants
  – May have negative consequences                        – Glucose, fructose, sucrose
     • Silica may lower digestion of fiber. Found in      – Starch, a polymer of glucose
       grasses and up to 30% of weight of Equisetum
                                                       • Structural -
• Minerals quantified by atomic absorption                – Cellulose – Glucose polymer resistant to digestion by
  and colorimetric procedures                               vertebrate enzymes
• Ash is sum of all inorganic material                    – Hemicellulose – A diverse group of polymers of other
                                                            sugar compounds. Hydrolyzed by acids and bases
  – Burn in muffle furnace at 500-600 C for 2-4
                                                            and thus partially digested by vertebrates.
    hrs. Weigh sample before and after
                                                          – Pectin – Soluble fiber in fruit and dicots.

     Nutrient Analysis                                      Plant Compounds
• Lipids – High energy molecules                        • Lignin – large, aromatic, nonsaccharide
  – Fatty acids and triglycerides used for energy         polymer that makes plant cell wall rigid
  – Waxes, volatile oils also lipids but not used by      – Not digestible by vertebrate or symbiotic
                                                            microbes. Common in woody plants > some
    animals for energy
                                                            dicots > grasses
• Protein – Discussed in detail earlier                   – Reduces digestion of cellulose
• Protective or defensive compounds                     • Cutin and subrin – aromatic polymers
  – Plant chemicals that reduce herbivory                 resistant to digestion.
     • Dilute nutrients                                   – Important in wound healing and as a physical
     • Reduce digestibility                                 barrier. In woody plants, absent from grasses
     • Affect animal’s metabolism (toxicity)              – Reduce digestion of cellulose.

     Nutrient Analysis                                       Nutrient Analysis
• Proximate Analysis – Basis of much of our             • Ether Extract – Crude fat
  forage analysis. Has been used for over a               – Soak sample in ether to dissolve lipids
  century.                                                – Use apparatus that continually washes
                                                            sample with ether
                                                          – Weigh sample before and after ether extract
                                                          – Ether also extracts pigments, waxes, volatile
                  Insert Figure of Proximate Analysis
                                                            oils, resins, sterols, etc… Thus term crude fat
                                                        • Crude Fiber – Meant to be the undigested
                                                          portion of the food.
                                                          – Boil 30 min in dilute H2SO4 and 30 min in
                                                            dilute NaOH. Weigh before and after.

     Nutrient Analysis                                       Nutrient Analysis
• Crude Protein – Measure nitrogen.                     • Ether extract, Kjeldahl, and ash widely
  Variety of techniques. Kjeldahl is common               used
  – Boil in concentrated sulfuric acid with catalyst    • Crude fiber has problems
  – Add NaOH to release NH3, which is captured            – Hemicellulose and lignin soluble in acid or
    in a weak acid                                          alkali; thus counted in NFE fraction.
  – Titrate acid to determine N in sample               • In 1960s, Detergent Fiber Analysis
• Nitrogen Free Extract = 100 – Fat –                     developed (Van Soest analysis)
  Protein – Fiber – Ash                                   – Plant can be divided into
  – Suppose to be most digestible portion of feed            • cell contents, highly digestible
  – Will reflect mistakes from all other analyses            • cell wall, requires microbes to digest

Nutrient Analysis                                                                                                  Nutrient
  • Insert Figure showing cell                                                                                     Analysis
    contents and cell wall

                                                                                                                   Detergent                • Insert Figure
                                                                                                                                              showing detergent
                                                                                                                     Fiber                    fiber analysis

Nutrient Analysis                                                                                                       Nutrient Analysis
                                                                                                                   • Total dietary fiber – developed to analyze
                                                                                                                     human foods, i.e. foods eaten by
    • Insert Figure                                                                                                  monogastric species.
      comparing results                                                                                              – Fats are removed by treatment with ether
      of crude and                                                                                                   – Enzymes remove protein and starch
      detergent fiber                                                                                                – Ethanol used to precipitate soluble fiber
                                                                                                                     – Sample filtered and residue is TDF

TDF vs. Digestibility                                                                                                   Nutrient Analysis
                D r y M a tte r M e ta b o liz a b ility


                                                                         y = -1.03x + 0.90
                                                      0.4                      2
                                                                             R = 0.77

                                                               0   0.1   0.2         0.3         0.4   0.5   0.6
                                                                               % Dietary Fiber

                Dry matter metabolizability vs. TDF
                for white-winged doves

Nutrient Analysis


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Description: nutrient is a food can provide energy to the body, body composition and tissue repair and the physiologic function of chemical composition. Those who can maintain health and to provide growth, development and labor required for a variety of substances called nutrients. Essential nutrients the human body are protein, fat, carbohydrates, minerals, vitamins, water and other six.