Animal Nutrition Test 1

Chemical element or compound required for normal reproduction, growth, lactation or maintenance

1. Water

2. Protein

3. Amino Acids

4. Carbs

5. Lipids

6. Vitamins

7. Inorganic elements (minerals)

1. Species

2. Productive function (gestation, lactation, growth, maintenance)

3. Age

4. Breed or genetics

Animal Sources have: low fiber, low carbs, higher fat, higher protein and more uniform

dry in oven at 105 degree C until no change in weight

1. Degredation - release N and put in soluble form

2. Liberation of Ammonia - neutralize sample to release NH3 gas

3. Capture of Ammonia - use boric acid to capture NH3

4. Back-Titration - amount of boric acid that is unreacted is determined by titration

The more N = the less boric acid

No N = no unreacted boric acid

Their low amount of true fats

Ether extraction does not recover fatty acid soaps in feces and gives a falsely high fat digestibility

cellulose, hemicellulose and lignin

1. Boil ether extract sample in 1.25% H2SO4

2. Boil that in 1.25% NaOH

3. Filter

4. Dry

5. Combustion in furnace

6. Loss during combustion is CF

Original sample - water - ether extract - CP - CF - Ash

NFE = non-structural carbohydrates

Most prone to error because not measured

1. Neutral Detergent Fiber

2. Acid Detergent Fiber

3. Lignin

Forage boiled in SDS and EDTA at pH = 7

Recovers Hemicellulose, cellulose, and lignin

Amylase included to ensure starch is degraded

Ensures most protein are degraded, but can remove disulfide bonds and solubilize lignin and make NDF more degradable

NDF residue boiled in H2SO4 and CTAB

recovers cellulose and lignin

1. ADF residue incubated in 72% H2SO4

hydrolyzes cellulose and recoers lignin

2. ADF oxidized with KMnO4 (removes lignin, it is measured as weight loss)

Hydrolysis and HPLC

CHONS combustion

Atomic absorption spectroscopy

bomb calorimetry

gas-liquid chromatography or HPLC

Strengths: inexpensive, fast, conditions similar to production, responses easy to measure, commercial interest

Weaknesses: measured responses more variable, does not show mechanism behind response

ADG, F:G, milk production

measures proportion of nutrients in feed or diet that are absorbed from GIT

group of animals fed test diet

Adaptation (3-10 d)

Collection (4-10 d)

(nutrient intake - nutrient in feces) / nutrient intake x 100

(nutrient intake - nutrient in feces + microbial and endogenous nutrient in feces) x (nutrient intake to the -1 power) x 100

microbial and endogenous N in feces

1. Feeding low-protein diet

2. Feeding several levels of protein and extrapolate to protein intake = 0

3. Feeding completely digestible protein

Determine digestion in specific GIT site, not just total tract

Facilitated by cannulation

(nutrient flow at duodenum - nutrient flow at ileum) / (nutrient flow at duodenum) x 100

100 - (marker in feed/marker in feces) x (nutrient in feed/nutrient in feces) x 100

1. Internal = lignin, acid-insoluble ash, indigestible NDF

2. External = chromic oxide, rare earth elements

Determines if there is a net retention (+ balance) or net loss (- balance)

Nutrient balance = nutrient intake - nutrient excretion

To determine nutrient requirements quantitatively

To establish essentiality

-Feed incubated in bottles containing rumen fluid inoculum

-Closed system

-Used to determine feed digestibility and fermentation end products

AKA chemostat

-Feed incubated in vessels with rumen fluid inoculum

-Continuous addition of substrate and removal of end products

-Open system

-Used to determine feed digestibility, fermentation end products and microbial efficiency

Feed incubated in rumen inside bag, feed digested by microbes and passes through bag pores

Used to measure feed digestibility and digestion rates

Percentage of absorbed N that is available for body productive functions (not excreted)

Measures efficiency of growth by comparing growth over 1-2 week period of:

1) diet containing test protein to

2) protein-free diet

NPU = (body N with test protein - body N with protein free diet) / total N intake

Break point in plasma AA or urea is related to its requirement

Meat eaters = cats, sharks

Mixed, opportunistic eaters = dogs, humans, pigs, chickens

insect eaters = bats, swallows, anteaters

seed and nut eaters = sparrows, quail

fruit eater = fruit bats, new world monkeys

forage, foliage eaters

Grazers = cattle, horses

Browsers = deer, rabbits

Intermediate Feeders = sheep, goats

Ruminants - mainly herbivores

Animals that have digestion carried out largely by enzymes produced by microbes in the gut

Allo = other

Monogastrics - mainly non-herbivores

Animals that have digestion carried out largely by enzymes produced by the animal itself

Auto = self

1. Rumen = particle retention and microbial fermentation

2. Reticulum = same

3. Omasum = reduces feed particle size and absorbs water and VFA

4. Abomasum = glandular stomach

foregut ; hindgut

hindgut ; foregut

1. Bacteria - activity of different substrates

2. Protozoa - activity of different substrates

3. Fungi - activity towards fiber

4. Methanogens - Produce methane

5. Viruses - lyse bacteria and cause protein turnover

1. Cellulose-degrading bacteria (cellulolytics)

2. Hemicellulose and pectin degrading bacteria

3. Starch-degrading bacteria

4. Protein degrading bacteria

5. Amino-Acid degrading bacteria

6. Sugar-utilizing bacteria

7. Utilizers of short-chain fatty acids

8. Lipolytic bacteria

1. Crop - temporary storage of food

2. Gizzard - reduction in feed particle size

3. Proventriculous - true stomach

1. Digestive enzymes enter to break down NSC, protein, and nucleic acids

2. Nutrients absorbed (jejunum and ileum)

3. Bile released from liver to emulsify fat and create alkaline environment optimal for enzymatic digestion

1. Fermentation of fiber and other components

2. Absorption of water and VFA

3. Minor importance in non-herbivores

1. Ferment fiber and other components to VFA

2. Synthesize protein from feed N and absorbed in small intestine (ruminants)

3. Synthesize B vitamins (ruminants)

4. Deactivation of toxins

1. Entodiniomorphid - cilia in tufts - "eaters"

2. Isotrichid - cilia all over surface - "drinkers"