-
food inputs
energy, protein, vitamins, minerals, essential fatty acids
-
food losses
- digestive- fecal
- metabolic- urine, methane, heat
-
food outputs
meat, milk, eggs, companion animals
-
which age group has the greatest loss of food resources
adult
-
basic principles of nutrition
- stage of development
- digestive physiology
- dentition
- feeding behavior
-
nutritional relevance
ruminant- rumen, reticulum, omasum,
- large fermentation vessel
- microflora
- degrade plant fiber
- products absorbed
-
nutritional relevance
ruminant - stomach, abomasum, duodenum, ileum
- small intestine
- endogenous enzymes
- nutrient abosorption
-
nutritional relevance
ruminant - caecum, colon, rectum
- large intestine
- further microbial activity
- products absorbed
- resorption water, minerals
-
salivary gland enzyme
salivary amylase -startch
-
gastric mucosa enzyme (stomach)
pepsin - protein
-
pancreas enzymes (small intestine)
- trypsin - protein
- chymotrypsin - protein
- pancreatic lipase - triglyceride
- pancreatic alpha-amylase - starch
- ribonuclease - RNA
- Deoxyribonuclease - DNA
-
intestinsal mucosa enzymes
- aminopeptidase - peptides
- dipeptidase - dipeptides
- maltase - maltose
- lactase - lactose
-
ruminant digestive physiology
- utilise plant fiber
- essentially grazers
- herbivores
-
non-ruminant digestive physiology
- cannot use plant fiber to a great extent
- prefer less complex materials (lower fiber)
-
non-ruminants which eat plants digestive physiology
- hind gut fermenters
- horse, rabbit
-
relative size of GIT region
ruminant
mainly to the front, rumen occupies considerable space 70-19-11
-
relative size of GIT
non-ruminants -
- fairly evenly distributed, both endogenous digestion and some hind-gut fermentation
- (cat )-very limited hind-gut fermentation
-
relative size of GIT
Hind-gut fermenters-
extensive caecal fermentation
-
Rumen microflora
- bacteria 10^9ml content (>60 species);
- protozoa (10^6 ml content);
- fungi
- influenced by diet
-
rumen products
- VFA's (4 kg per day) -main acetate
- microbial protein
- gasses - (burp) 30 l/hr; 40% co2 30-40% CH4
-
rumen homeostasis
- pH 5.5-6.5
- VFA's rapidly absorbed,
- salivary buffers (phosphate, bicarbonate) w/o usual anitibotic
-
good grass quality
- vegetative -leaf and stem - tillers hard autumn grazing
- clover-high nitrogen
- ensiled whole crop cereals
- alfalfa
-
poor grass quality
- flowers (inflorescence) reduced nutritonal value/ high fiber
- reduced mineral intake - Ca - milk fever
- poor growth
- build-up of pasture worms (zero grazing better)
-
good quality silage
- no air (anaerobic) pack down
- rapid fermentation
- reduce moisture
- pH 4 (low pH = pathogens)
-
silage hazards
- uncontrolled fermentation
- variable conditions
- pathogenic micro-organisms
- toxic chemicals w/ bacterial toxins
- excess acidity
-
silage pathogens
- e. coli -diarrhea, mastitis
- listeria monocytogenes-listeriosis, silage eye
- fungal spores - respiratory distress
- botulism
- cryptosporidium parvum
- actinomycetes
- penicillim roqueforti
-
enterobacteria risk factors
- animal manure spread on grass crop
- slow acidification -<sugar, >water
- low concentration of undissociated lactic acid in silage
- low acid, high NH3, high mineral concentration
-
L. monocytogens risk factors
- contaminated soil
- >4.5 pH
- oxygen infiltration
- mold
- mostly on outer layer of bale
-
botulism risk factors
- silage contaminated w/ carcasses
- wet silage >4.5 pH
-
acidosis & symptoms
acute - over eating on rapidly fermented starch +suga
rchronic- too much concentrate, little physical activity
- high WSC in crop
- low DM at harvest
- low buffering capacity
- innoculant additive
- short cut
- low pH < 4.0
- rapidly digested carbs in supplement feed
-
clinical signs of Acidosis
treat- NaHCo3, walk, long fiber
- >intake of minerals
- low milk fat
- drinking urin
- straw
- change in silage intake
- regurgitation
- diarrhea, hyperventilation, lethargy, bloat
-
Birds
- particulate feeders,
- crop = storage > esophagus capacity, mucus
- proventriculus-mucus, HCL, pepsinogen
- gizzard-grit, grinds
-
dentition - herbivores
- large molars and premolars
- grind food into smaller pieces
-
dentition - omnivores
combinations - proportions depend on main components of diet
-
dentition - carnivores
large incisors and canines
-
feeding behavior
trickle feeders -
- horse and rabbit
- large number of small meals
-
feeding behavior
grazing herbivores -
- several hours at pasture
- rumination
-
feeding behavior
carnivores -
- variation
- large - large meal every couple of days
- small - a little bit now and again
- prefer warmer food
-
feeding behaviour
Omnivores -
- variation
- canines - large meals occasionally and regular daily meals
-
objectives in nutrition
- relate input to output- performance health
- quality optimum input, biological response, economics
-
Ideal feed evaluation system
- 1. based upon sound scientific concepts
- 2. allow prediction of responses to a given intake
- 3. easy to use
- 4. sufficiently accurate to allow substitution of one feedstuff for another
-
feed evaluation - principles
1. chemical/p[hysical nature of diet
2. productive response
- moving from 1->2 losses in digestion, absorption, assimilation of dietary energy and nutrients
- - increasingly more a function of the animal and less a charateristic of the diet
(need a diet that does both)
-
Total digestible nutrients (TND) feed evaluation system
- widely used, not effective, based on chemical constituents (proximate analysis)
- organic matter(CP, CF, NFE, EE), inorganic matter(ash)
- sum of total constituents
- total * digestibility(%)=content of digestible component
-
TND Criticism
- 1. assumes- total nitrogen, all N is protein
- 2. variables in method of chemical determination (solvent, time of reflux)
- 3. CP- complex carbs are dissolved, suppose to represent non-digestible component (does have a low amount)
- 4. digestible component? determens difference =errors
- NOT scientific - does not predict response
-
recent developments in feed evaluation
- what animal actually requires
- energy (not a nutrient) yielding potential
- protein
- minerals
- vitamins
- essential fatty acids
-
mineral interactions
Ca:P
-
mineral:vit interaction
selenium:vit E
-
vit: essesntial fatty acid interaction
vit E : linoleic acid
-
energy : protein
response to dietary protein influenced by presence of energe
-
Water- chemial analysis
- overlooked, simplest
- cheap
- moisture content = deterioration
- fermentation, mold, mycotoxicoses, mycotoxins
-
Fiber - chemical analyses
- NDF- insoluble in neutral detergent
- lignin, cellulose, hemicellulose "plant cell wall"
- ADF -insolube in acid detergent
- lignin, cellulose
NDF-ADF=hemicelluloses "active plant fiber"
-
gross energy
- glucose- 15.6
- lipid- 39.4
- protein- 20.1
- energy potential depends on degree the components are digested
-
sources of energy
- protein
- lipid- plant oils, animal fats
- carbs(starch, sugars, fiber)- cereal greains, molasses, forages
-
gross energy GE
energy released when a dietary raw material or complete feed is completely combusted in an atmosphere of oxygen
-
digestible energy DE
- energy available following digestion
- DE=GE-fecal energy
-
metabolism energy ME
- energy retained
- ME=GE-(fecal=urinary+methane)
-
net energy NE
- energy available for maintenance and production
- NE=GE-(fecal+urinary+methane+heat increment)
-
partitioning of dietary energy
- Feces - ruminants most loss
- heat incriment- non ruminants most loss
- urine methane- lots in fowl
- swine & fowl- highest production
- - ruminants do utilize low quality materials that the others can't use
-
best estimate of dietary energy
Net energy- difficult to measure, depends on multiple variables
-
small intestine digestion
glucose
-
large intestine fermentation
- volatile fatty acids
- utilize glucose>VFA
- NE from DE small>large
-
ME - metabolic energy
- need fecal and urinary output(~3%)
- hard to separte metabolic and digestice losses
- ME = poultry
- AME= apparent ME- needs endogenous losses (cells, bact, enzymes)
- MEn = corrected to zero nitrogen retention
- high losses of methane in ruminants = ME
-
DE Digestible energy
- counts variable losses of ingested dietary energy, not urine
- inaccurate w/ different conditions
- DE = Pigs
-
GE gross energy
- easy,
- does not count any losses during digestion and metabolism
- alone - poor for formulation of diet
-
high concentrate diets cause
high amounts of lactobacilli = acidosis
-
Rumen-Simple carbs
starch, fructans =fermented to VFA's
-
Rumen Energy- complex carbs (Non starch polysaccaride)
- fermented to VFA = very complex, inert
- NSP: by pass, coated so pass through rumen
- cellulose, pectins, hemicelluloses, pentosans
-
Rumen Energy- fats/oils
(in free state, reduce rumen activity feed as bypass)
Unsaturated- depress DMI, impair fiber digestion, toxic to bacteia, eats less, impair rumen fermetation
Saturated <6% - doesn't affect DMI, rumen inert, Stearic acid (digestible) decrease fat accumulation in liver, improves repro perfomance
-
Pyruvic Acid -> volatile fatty acid
- Acetate( highest)(VFA)
- Butrate (VFA)
- lactate -> concentrate -> propionate(VFA)
- succinate -> forage -> proprionate(VFA)
-
Net energy for ruminants
- NE= ME*k(efficiency - maintenance)
- k = maintenance - .72
- lactation - .62
- growth - .62
-
Neutal detergen fiber (NDF)
- increases acetate: good for milk quality, precursor for milf fat
- in: long grass, silage, rolled cereals, dried grass, concentrates
-
animal trials to determine energy value
measure digestibility/ metabloism/ nutrient balance allowing precise data on value to be dtermined
-
animal trials - compund diet
comparatively easy to determine the measurements
-
animal trials - raw materials
- can't be evaluated independently
- rate of inclusion to a basal diet- be where compund diets are at
-
animal balance studies
lengthy, expensive, may compromise animal welfare
-
predict DE from chemical content
- -non ruminants can't digest fiber (negative correlation between DE and "fiber)
- -Crude Fiber does not fraction out fiber that has nutritional relvance BUT still good results
- -emperical nature of predictions
-
Problems with Fiber - NSP (non-startch polysaccharide)
- -a chemical and will have different effects depending on the origin
- - har d to derive chemical measurements w/ biological relevance
- -measuring chemical and biological variation has to be done in separate samples within the same species
- -adults digest fiber better (need to evaluate different ages also)
-
prediction of DE/ME from chemical content
- -use several chemical variables
- -usually confined to compund diets
- - increase in % in chemical components
-
NIRS - near infra-red spectroscopy
- -chemical bonds (C, O, H, N) absorb different wave lengths
- -scan feed sample allows rapid estimate of composition which can then predict ME
-
DOMD - digestible organic matter in the dry matter
- rumen fluid used to digest forage sample
- ME = .16 DOMD%
-
-
carb - disaccharides
- 2 carb monomers, dipeptides
- sucrose = glucose + fructose
- Lactose = glucose + galactose
- Maltose = glucaose + glucose
-
carb - polysaccarides: digestible
Starch - polymer of glucose, alpha bonds (1-4), stored in plants, amylase breaks down (1-4)
amylopectin - polymer of glucose(1-4 & 1-6) less common
-
polysaccharides: non-digestible, fermentable
- Cellulose: polymer of glucose, beta (1-6), most common, plant structure, little fermentation
- Hemicelluloses: some hind gut fermentation, polymers of hexoses and pentoses
- Pectins: not digested, polymers of galacturonic acid
- oligosaccharides: glucose, fructose & galactose, bonds can't be broken by enzymes
-
Lignin
Named as a polysaccharide: nondigestible, fermentable, but NOT a carb but phenolic based compound
-
Phytic acid - carbohydrate-based molecule
- how plant stores P
- binds minerals
- needs phytase to break off minerals when plants need, can be added to diets
- P not readily available for animal - excrete in feces which leads to polution
-
Cell wall complexity
- pentosans, hexosans, mixed, cellulose
- -when bond together make it harder for fermentation
-
structure of nonstarch carbs
- Pentoses: Xylose, Arabinose
- Hexose: glucose, galactose, mannose
- -most common, less complex the more soluble
-
water insoluble Non-Starch carbs
- cellulose
- hemicellulose
- pectins
-
Barley
- Beta glucan- cant break down
- -dissolves in water and becomes sticky
- ok for adult pigs but not for birds
-
Crude fiber problems
- it does not simulate what really happens in the GI
- - sticky stomach from barley
-
legume: alpha galactosides
- raffinose: sucrose-galactose (usually low)
- stachyose: sucrose-galactose-galactose (high in soy)
- verbascose: sucrose-galactose-galactose-galatose
-
Cell contents
- starch, simple sugars- stored within cell
- -main enzyme amylase (glucose)
- -stomach pH too low for digestion
- to much starch in caecum = diarrhea enteropathogens (coliforms)
-
caecotrophy
rabbits eating their fecal pellets so that they can digest the fiber in the stomach b/c encased in mucus and increases the pH of stomach
-
cell wall
- no endogenous enzymes present
- -limited digestion in small intestine (bacteria)
- -fermented to VFAs in caecm
-
lactose
in mammal milk, small fat globs, lactase in juviniles to digest
-
alpha amylase
- saliva, inactive in stomach, in pancreas
- - digest starch, dextrin
-
Small intestine enzymes
- alpha- oligo- glucosidase, galactosidase, fructofuranosidase
- digests- maltose, dextrins, lactose, sucrose
-
starch digestion
- major energy-yielding component in diets for non-ruminants
- -complex molecule
- -crystalline in raw state = less digestion (peas greatest)
- -needs processing
-
Weaning
stressfull, damage to vilia, sever decrease in digestive enzymes for 10-12 days
-
sites of starch digestion
- slow release in SI - beneficial to poultry
- if not in SI goes to LI for fermentation
- Good: more acid, reduced pathogen
- Bad: microb proliferation, diarrhea, death, dehydatration
-
Lipids
- -diverse group of compounds, not soluble in water, only non-polar organic solvents
- -related to fatty acids
-
Fatty acids
- long chain carbon atoms with terminal methly and carboxy group
- saturated - single bonds (solid) animal fats
- unsaturated - double bonds (liquid)
-
fish oils
long chains and highly unsaturated, 4-5 double bonds
-
coconut oil
highly unsatuated
-
lipid classification: glycerol-based
- simple > fat/oil
- compund > phosphoglycerides > lecithin / cephalins
- > glycolipids > glucolipids / galactolipids
- (cell membranes)
-
lipid classification: non-glycerol based
- sphingomyelins
- cerebrosides
- waxes
- steroids
- terpenes
- prostaglandins (cell function)
-
Triacylgylercerol (triglycerides)
glycerol (back bone)+ 3 fatty acids = water + triglyceride
-
complex lipid
- lecithin: emuslified fat in nature, phospholipid
- sterol cholesterol: important in diet
- cholecalciferol Vit D3: lipid
-
lipolysis
pancreatic lipase, emulsification, micelle formation, droplet absorption
-
long chain FA
saturated
sterols, vitamins
non-polar, poor solubitity in bile salt solution, limited entry into micellar phase
-
medium chain FA
Long chain unsaturated
monoglycerides
- polar solutes, swelling amphiphiles
- - high solubility in bile salt, enter micelle
- -promot of non-polar solutes into micelle phase
-
implications of chemical structure on digestion of fats
- unsaturated > saturated
- Tri > free fatty acids
- medium chain > long chain
- interactions between fats of differing saturation
-
fat digestion - juveniles
- - limited bile and pancreatic lipase production
- - gastric lipase (serous glands of tongue)
- FA absorbed in stomach
- some TAG & DAG goes to SI
- hard to get fat from dry diet
-
fat digestion of juvinels in SI
- oil drop coated in bile
- pancreatic co-lipase absorbed onto surface of droplet
- acts as anchor for pancreatic lipase
- - hydrolyses of TAG/DAG(Ca++ needed)
-
micelle
- molecules arranged in specific alignment
- lipases act at surface
-
Absorption of Free faty acids
- micelle contact w/ membranes
- - energy dependent (FA binding protein) favor unsaturated
- - bile salts absorbed further on down the SI (recirculated by enter hepatic circulation)
-
fat energy
- - growing and endurance animals need high fat (high in energy) double than carbs
- - can break down into ketone bodies which are toxic
- - chemical structure has major effect on energy-yielding value
-
chemial structure of fats
- degree of composition
- - saturation
- - chain length (14-20 carbons)
- - triglyceride / free fatty acid
-
Essential fatty acids
- Linoleic acid - 18:2 N6 (higher content, less firm)
- Linolenic acid - 18:3 N3
- - can't be interconverted, or synthesized from other fats
- - cell messengers
- - prostaglandins
- - precursors
-
Essential fatty acid metabloism
- desaturase - add double bond
- elongase - adds 2 carbons
- both N3 and 6 start with desaturase then elongase and switch off
-
essential fatty acids and non essential fatty acids
- compete for enzymes
- Ex - oleic can create deficiency of EFA
- efficiencies further up the path are much better
-
Eicosapentaenoic Acid - N3 pathway
- 20:5
- only in animal and fish sources, most inefficient diet so need this in diet
- - intermediate
-
Zinc and Iron
- involved in chain elongation and desauturation
- Zinc deficiency: can reduce delta desaturase acitivity
- exacerbated by: high genetic potential, high Ca(inhibits Zn absorption), fats which inhibit EFA metabloism
- (becoming more previlant)
-
Requirments for EFA
- 5:1 ratio of N6 - N3
- - better performance, reproduction, immune status, appearance
- - need high level of antioxidants to prevent oxidation
- - long chains are unstable
- - don't use PV to assess oxidation?
-
healthy fat intake
- dietary < 1/3 total energy intake
- saturated < 1/3 total fat intake
- MUFA:PUFA 2:1
-
increased unsaturation
- more unstable cooked and fresh
- more oxidiation - healthier, can become rancid
- softer fat- harder to cut
- metabloic problems when digested
-
developments in meat quality /science
- oxidative stability - TBA number, volatile products
- flavor/aroma - during stoage and production
-
healthier pig meat
- interaction with vit E
- PUFA L E above threshold (healthier) but might break down to early in storage and cooking
-
Macro mineral
Ca, P, K, Na, Cl, Mg, S and others
-
Trace minerals
- Fe, I, Zn, CU, Mn, Se, Co, Mo, Cr
- current accurate list
-
Minerals - general
- co-factors in enzymes (Mn in TCA cycle)
- Electrolytes (Na, K, Cl)
- Components of other molecules (Co-B12, I-thyroxine, Fe-hemaglobin)
- structural role (Ca, P, Mg = bone)
-
Macro:electrolyte balance
- Na: cation of extracellular fluid, transport across membrane, maintain membrane potential (plasma)
- Cl: anion of extracellular fluid
- K: cytosol, membrane action potentials
-
Water balance with Minerals
- important for ions, hormones
- need for angiotensin ll and arginine
- affects - CNS, Liver, Kidney
-
Na and K balance
Na deficiency: kidney>renin>liver> aldosterone ll>adrenals>aldosterone =Renal excretion of K and re-sorption of Na
-
Ca and P
- bone mineralisation - hydroxyapatite, non-crystalline phosphates, calcium carbonates
- Ca: muscle contraction, neuronal transmission, blood clot, enzyme activit
- P: phospholipids, ATP creatine phosphate, phosphorylation, phosphate buffers
-
Ca and D3 (1,25 dihydroxy choleclciferol)
- Ca deficiency increase D3
- Ca excess decrease in D3
- CaBP dependent on active for of D3
-
Hypocalcaemia
Hypo more common: secretion of parathyroid Hormone, kidney, syn of D3, increase intestinal Ca absorption, or renal resorption of Ca = mobilisation of bone Ca
-
Hypercalcaemia
- 1. secretion of calcitonin = no renal Ca resorption
- 2. inhibition of PTH, Kidney, decrease in D3 = low intestinal absorptionof Ca
- 3. secretion of Calcitonin CT = stop mobilisation of bone Ca
-
Milk fever
- high Ca after giving birth = difficult standing head to side, staggering
- - give oral Ca salts (borogluconate)
-
Trace minerals
small quanitites, to much = toxic
-
Iron
- in hemaglobin 2/3, proteins and co-factors
- 1/4 stored in bone marrow
- rest in muscle and enzymes
- Ferrous sulphate and chloride - good
- ferric oxide and ferrous carbonate - poor
-
Iron in animals
- deficiency in foraging animals
- piglets - IM post partum ferrpus sulphate
- sow milk low levels
- loss at navel
-
Copper
- function of enzymes (ferroxidase = Cu trans + Fe oxid)
- cytochrome oxidase = ATP synthesis
- Tyrosinase = melanin
- monoamine oxidase = neurotransmitters
-
Zinc
- associated with enzymes
- - active site of component (carbonic anhydrase, alcohol dehydrogenase, superoxide dismutase)
- -structural element of proteins recognize DNA sequences
- -gene expression/metablism of proteins
-
Selenium
- antioxidant with Vit E, regenerates E
- Co-factor in Glutathione peroxidase- protect from oxidative damage
- - co-factor for thyroid hormones
-
Mineral availability
ultimate response in the animal, unclear as to how much is available
-
Phosphorus
expensive, need for bone growth and strength, give to animals that are going to be kept for breeding stock
-
Intro to Vitamins
- - organic, required in often in small amounts
- - can't be synthesised by the animals (ex. Vit C)
- - performance promoting effect
-
definition of Nutrient
specific molecule w/ a precise metabloic function
-
Fat soluble vitamins
- A: sight, epithelial cells
- D: regulats intestion absorption & metabof Ca
- E: anti-oxidant, immunity
- K: synthesis of compunds involved in coagulation
-
Vitamin A
- Retinol - 7 isomers, trans has greatest activity
- percursor - Beta carotene
- cats: can't transform Beta carotene into Vitamin A, need the precursor, can't regulate Vit A uptake = toxicity
-
Vitamin A decficiency
- retina - poor sight in dark, blood concentrations, responds fast to treatment
- Xerophthalmia- drying of cornea, common cause of blindness
- stage 1: xerosis, dryness of conjunctiva
- stage 2: keratomalacia, softening of the cornea & 2nd infections, scarring
-
Vitamin D
pre-vitamin D3: only 1 hydroxy group, most active form
- D3- 2 hydroxy groups, most active form
- -UV radiation D3 is formed from 7 dehydrocholesterol
- deficiencies = bone deformaties
- birds and furry animals get from oil on fur/feathers & consumed
-
Vitamin E
- alpha most active
- antioxidant-lipid oxidation, cell membranes
- stimulation of immune response, antibody production, meat stability
- Selenium interactions are complementary (free radicals)
- natural not as stable, commercial are protected
-
Vitamin K
- anti-hemorhagic, K1 & K2
- coagulation factors - prothrombin, prconvertin, antihemophilic factor B, Stuart Factor
- Bone metabloism, vascular biology
- deficiency - longer to clot, rodenticides block K1
-
Vitamin B
- water soluble
- protein, carb, lipid, metabolism
- enzyme systems 1. transfer of molcular groups, 2. oxido-reduction reactions (thiamine to Niacin, B6 to B2)
-
B vitamin co-enzyme forms
- Niacin - NAD
- Riboflavin - FAD, FMN
- pantothenic acid - co-enzyme A
- Folic acid - tetrahydrofolate
-
B Vitamin carriers
- thiamine - aldehydes - pyruvate dehydrogenase
- NAD - H ion - alcohol dehydrogenase
- FAD - H ion - succinic dehydrogenase
- Coenzyme A - Acyl group - acetly CoA carboxylase
-
Acetly Co-enzyme A (versatility)
goes to Krebs cycle, steroids, hormones, bile salts, cholesterol, acetoacetic acid, acetylations, acetylcholine, detoxifications, mucopolysaccharides
-
Thiamine
- deficiency - nervous system and heart b/c need for their high amount of oxidation
- poultry- anorexia, unsteady gate, stargazing
- ruminants - listless, going in circles,muscle tremors, consuming ferns
-
Pantothenic acid
- deficiency - disorders of nervous, gastic, and immune system, lower growth rate, skin lesions and changes in hair coat, alterations in lipid and card metab
- - rumen produces in high amounts
-
liver vitamin storage
A, D, B12, for some time
-
Cats and Vit A
to much vit A in liver so don't feed cats liver, causes muscle soreness and sensitivity to touch
-
Intro to Protein
- made of AA (amino group NH2, R group, carboxylic group COOH)
- - peptide bonds, sequence determines protein function
-
Primary protein structure
is sequence of a chain of amino acids
-
Secondary protein structure
occurs when the sequence of AA are linked by hydrogen bonds
-
tertiary protein structure
occurs when certain attractions are present between alpha helices and pleated sheets
-
quaternary protein structure
is a protein consisting of more than one AA chain
-
Animal protein sources
milk and animal co-products, fish products
meals, whey,
-
plant protein sources
oilseeds, legumes,
soya canola, palm kernal, cotton seed meal, peas, beans
-
Crude Protein
- - determined by N x 6.25
- - does not count for variable N content of protein, assumes all N is from protein, does not consider protein quality
- - not sufficient to estimate protein quality
-
measurements of protein quality
- Protein efficiency ratio- PER
- Gross Protein Value- GPV
- Absolute amount- does not use AA, biological value
- -overall value of a group of raw materials can be calcualted from the sum of their individual values
- don't count individual AA
-
essential AA
- in diet
- Iso, lue, val, lys, meth, thre, pheny, tryp, hist
-
conditionally essential AA
- can't be synthesised in vivo fast enough for high performance
- arg, cyst, gly, pro, ser, tyro
-
non-essential AA
- can be synthesised in body
- alan, asp, asparagine, glutamate, glutamine
-
Ideal protein
- optimum performance
- 1. all essential AA
- 2. AA in the correct proportion balanceone to the other
-
-
-
diets of beans and peas
- lower growth and increased environmental pressure
- deficient in M+C or THR
- animal proteins are usually better quality
-
leaf germ proteins
- functional: higher content of essential AA
- often not bound, higher digestibility
-
seed/tuber proteins
- storage: poor content of essential AA
- bound lower digestibility
-
first limiting AA
performance is restricted to the first limiting AA, no benefit in providing extra of others when there is 1 limited AA
-
AA = performance
- meat, eggs, milk
- coat condition, longevity
- cell membrane permeability, RBC integrity
- metabolic profiles, plasma urea
-
Ileal digestibility
- better than LI: b/c N in LI has no nutritional value, alters AA by de- and trans- amination
- - hard to measure Ileal digestivity
-
Protein in Rumen
- 1. undegradable- not digested in SI , feces
- -by pass, digested in SI, metabolisable protein
- 2.degradable protein- peptides/AA, mirco protein, metabolisable protein
-
Non Protein Nitrogen in Rumen
- 1.NH3- liver, kidney, urine
- - microb protein, metabolisable protein
- 2. salivary glands- liver, kidney, urine
-
balance of energy and protein
- protein and fiber need to work together,
- starch free- high in CP (ethanol production)
-
Rumen functions adequately
- breakdown of fiber- VFA
- protein- microbe protein and ammonia
- digestion in SI
- feed the animal and the rumen
-
Rumen does not Function adequately
- reduced breakdown of dietary components particularly "fiber"
- reduced overall dietary efficiency
-
Rumen digestion of protein in stomach
- acidic pH
- pepsin, parapepsin, rennin in ruminants,
- producing polypeptides
-
Rumenant digestion in SI
- pancreatic secretions- trypsin, chymotrypsin, elastase, caboxypeptidases A/B
- producing peptides oligopeptides + free AA
-
factors influencing protein digestion
protease inhibitors- reduce, growth rate and protein digestibility, increased demand for met and cys, pancreatic hypertrophy
-
soyben trypsin inhibitors
- Bowman Birk Inhibitor: 2 active sites, 71 AA, 7 disulphide bonds
- Kunitz Inhibitor: 1 active site, 181 AA, 2 Disulphide bonds
- (highest in soy less in peas and other plants)
-
High temperature processing
- 2 major ANFs are heat labile, reduced/eliminated by heat
- 1. Autoclaving- moist heat underpressure
- 2. Extrusion- wet or dry
- 3. micronising- gas burners heat ceramis tiles, emit IR waves
- 4. jet-sploding/expansion- material heated and explodes into area of low pressure
-
trypsin inhibitor
greater the intake the more the pancrease weights, are prominant in legumes
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