Exam 2 Flashcards
What do high starch diets cause in ruminants
-Rapid fermentation
-SCFA and lactic acid production
-Decrease in rumen pH
-rumen acidosis
-disruption in ruminal function
When is rumen acidosis subclinical
pH is approximately 5.5
What are subclinical signs that the ruminant is undergoing rumen acidosis
-Decreased Intake
Gain
When is rumen acidosis clinical
when the pH is less than five
Clinical Signs of rumen acidosis
increase lactic acid
metabolic acidosis
damage to papillae
microbial death and release of endotoxins
Is subclinical or clinical rumen acidosis more dangerous
subclinical because you can’t usually see the signs so then you can’t treat it or manage it
Associated problems with rumen acidosis
parakeratosis (hardening of the papillae tissue)
liver abscesses
laminitis
Rumen Acidosis prevention
-reduce grain
-feed additives (buffers, ionopheres)
-the chewing of cud also helps because it produces saliva and helps buffer the pH
Glucose homeostasis in ruminants
50-80mg/dl
Glucose homeostasis in simple stomachs
80-120mg/dl
Why is there reduced glucose fluctuations in ruminants
-more time spent eating and ruminating
-prolonged digesta flow
-steady VFA production
-continuous glucogenesis
Glucose requirements in ruminants
don’t typically feed glucose to meet energy requirements since it rapidly ferments and drops pH
Source of glucose precursors in ruminants
1.) propionate
2.) amino acids
3.) lactic acid
4.) glycerol
Source of gllucose for ruminats
25% comes from diet and 75% comes from gluconeogenesis from propionate
Lipids
-“Lipos’ meaning fat
-insoluble in H20
-Hydrocarbons-CH2-CH2-CH2
-Not a polymer
Lipids energy compared to glycogen
6x equivelant mass of glycogen
Short Chain Fatty Acids
2-5 carbons
soluble in water
Fatty Acids
Hydrocarbon chains with 2 or more carbon atoms and a carboxyl group
Medium chain fatty acids
6-12 carbons
soluble at physiological conditions
Long chain fatty acids
13-20 carbons
generally insoluble
Very long chain fatty acids
> 20 carbons (also insoluable)
Simple Lipids
Include fats and oils
-comprised of 3 fatty acids each in ester linkage with a single glycerol (triacylglycerol)
-Make up the largest fraction (~98%) of lipids in animal feeds
Glycolipids
-esters of glycerol with CHO
-widely present in plants and major lipid component of forages
-in animals, glycolipids serve as markers for cell recognition and as energy sources
-maintain cell membrane stability
Phospholipids
-fats complexed with phosphoric acid
-water insoluable and water soluble regions
-critical for membrane function
-most abundant biological membranes
Sphingolipids
-Based on sphingosine
-1870s-discovered in brain extracts
-abundant in brain tissues-sphingomyelon
-serve as adhesion sites for proteins, signaling and recognition
-meet,dairy,eggs and soybeans are good sources
Lipoproteins
-Lipids linked with proteins
-synthesized in SI and liver
-Protein emulsifies lipid
-Proportion of protein varies that relates to the density
-chylomicrons
3 carbon fatty acid
-propionic acid
-microbial action in the gut
4 carbon fatty acid
-microbial action in the gut
-used as energy in cells
-remove the acid you get butane
8 carbon fatty acid
-octanoic FA
-common name is caprylic acid
-made in the body
-if you remove the acid you get octane (which is in gas)
Properties that determine fatty acid function
-chain length
-degree of saturation
-location and type of double bond
Fatty acid chain length
-volatillity decreases with chain length
-14-16 Carbon-solid at room temp
-5-12 carbon-liquid at room temp
-Long chain fatty acids-higher melting point
Saturated fatty acid chains
pack tightly and form more rigid, organized aggregates (membranes) have a higher melting point than unsaturated fatty acids
Unsaturated fatty acids
bend and pack in a less ordered way, with greater potential for motion
what are the only lipids that need to be supplied in the diet
Omega-6 fatty acids (linoleic acid)
Omega-3 fatty acids (linolenic fatty acids)
Common saturated fatty acids
-Lauric 12:0
-Myristic 14:0
-Palmitic 16:0
-Stearic 18:0
Common Unsaturated Fatty Acids
Palmitoleic 16:1
Oleic 18:1
Linoleic 18:2
Linolenic 18:3
Cis Double bond
-kinked and hydrogens are on the same side
Trans double bond
straight and hydrogens are on opposite sides
Cell Membrane
-Holds components together
-protects intra and extra environment
-regulates entry and release of nutrients and gas
Temperature affect on membrane fluidity
when it cold phospholipids are found closer together and when its hot they move farther apart
Degree of unsaturation effect on membrane fluidity
saturated fatty acids have only single bonds with straight chains making them easy to pack. unsaturated fatty acids have 1 or multiple double bonds, these double bonds create kinks making it harder to pack tightly
Membrane fluidity in the cold without cholesterol
-rigid
-not as fluid/flexible
-may break
Membrane fluidity in the cold with cholesterol
increased fluidity and flexibility
Membrane fluidity in the heat without cholesterol
-too fluid/flexible
-won’t hold shape
Membrane fluidity in the heat with cholesterol
decrease fluidity and increase rigidity
Lipid Digestion in the mouth (non-ruminants)
lingual lipase hydrolyze TAGs
Lipid Digestion in the mouth (pre-ruminants)
saliva contains lipase known as pregastric esterase for limited TAGs hydrolysis
Lipid digestion in the mouth for ruminants
negligble salivary lipase activity
Lipid digestion in the stomach with non-ruminants
-proteases release lipids from feed
-ligual and gastric lipases (latter secreated in fundic region)
-Gastric lipase activity is higher in suckling neonates and higher toward milk TAGs
-pancreatic lipase is higher in adults
Fate of Lipids in the rumen
-hydrolysis of TAGs in the rumen
-unsaturated FA undergo rumen biohydrogenation
-a limit to fat inclusion in diet-generally about 8% supplemental fat (DM basis)
biohydrogenation
a process that occurs in the rumen in which bacteria convert unsaturated fatty acids (USFA) to saturated fatty acids (SFA)
Duodenal Lipolysis
-pancreatic lipase attaches to surface of triglyceride globules
-products are FFAs and 2MGs
When are pancreatic lipase very efficent
-neutral pH
-Mixing
-Bile Salts (emulsify lipids)
-Co-lipase
Micelles
20nm in diameter
-they make transport of fats and vitamins to the enterocyte membrane highly efficient
Micelle Formation
-Mono and FFa combine with bile and complex with other lipids to form micelles
Whats in a chylomicrons
apolipopproteins
-phospholipid and cholesteral coat core
Apolipoproteins
act as cofactors for enzymes or ligands
Lipoproteins core
TG and cholesterol
Lipoproteins shell
proteins and phospholipids
What has the highest ratio of lipids to protein
chylomicrons
Chylomicrons
-form in small intestine mucosal epithelial cells
-transport dietary lipids to adipose tissue
Very Low density lipoproteins
-form in hepatocytes
-transport endogenous lipids to adipocytes
Low Density Lipoproteins (bad cholesterol)
-carry 75% of total cholesterol in blood
-deliver to body cells for repair and synthesis
High Density ipoproteins (good cholesterol)
-remove excess cholesterol from body cells and blood
-deliver to liver for elimination
Lipogenesis
the conversion of glucose or amino acids into lipids and is stimulated by insulin
What are the intermediary links in lipogenesis
-glyceraldehyde-3-phosphate
-acetyl coenzyme a
Lipogenisis steps
1.) glycerol can be made from glucose through glycolysis
2.) two-carbon acyl units from acetyl CoA are linked together by fatty acid synthesis to form fatty acids
3.)one glycerol plus 3 fatty acids make a triglyceride
Lipolysis
-glycerol converted into glucose by conversion into glyceraldehyde-3-phosphate
-the resulting molecules of acetyl coenzyme A enter the krebs cycle
Oxaloacetate
allows entry of acetyl-CoA into citric acid cycle
When is oxaloacetate depleted
acetyl -CoA is converted into ketone bodies
Ketogenesis
as part of normal fatty acid catabolism two acetyl coA molecules can form acetoacetic acid which can then be converted to beta-hydroxybutyric acid and acetone
-the three substance formed are known as ketone bodies
Excess ketone bodies in blood
ketonemia
Excess ketone bodies in urine
ketonuria
Amphoteric molecules
can be both acids and bases
Peptide bonds
what bound amino acids together
What gives amino acids there charecterisitic
R-groups
Hydrophobic interactions
these amino acids orient themselves towards the center of the polypeptide to avoid the water
Disulphide Bridge
the amino acid cysteine forms a bond with another cysteine through its R groups
Hydrogen bonds
Polar R groups on the amino acids form binds with Polar R groups
Hydrophilic Interactions
These amino acids orient themselves outward to be close to the water
Ionic Bonds
Positively charged R groups bond together
Primary Protein Structure
Polypeptide strand
Secondary structure
-alpha helix
-beta pleated sheet
Tertiary Structure
folding of secondary structure
Quaternary Structure
polypeptide chains linked together in a specific manner
Protein Permutations
20 AA can from 400 dipeptides of 8000 different tripeptides
There are 20^n combinations of N amino acids
Sickle Cell Anemia
where an incorrect amino acid sequence interferes with the cell’s ability to carry oxygen
Mad cow disease
all the amino acids are there but they are folded wrong
Amphoteric Amino Acids
pH alters formation
May exist as
-uncharged molecules
-ionic charge
-mixture
Properties of amino acids
-acts as a buffer resisting pH change
-Acidic solution AA exist largely as Cations
-alkaline solution AA exist as anions
Transamination
transfer of the amine (nitrogen) molecule
Deamination
removal (cleave) of the amine (nitrogen) group
How are indespensible amino acids formed
provided in the diet, the microbes also supply them
Amino acid storage in body
-can’t be stored by the body in the same manner as fat and starch
-adequate intake is essential for optimal growth and health of animals
-excess results in wasting, pollution, digestive, hepatic and renal abnormalities
De Novo Synthesis
when essential AA are formed from indepesnible AA
Supply of Amino Acids
-exogenous proteins(digestion and absoprtion)
-tissue protein turnoer (mobilize one tissue to another)
-de novo synthesis
Disposal of excess AA
-oxidation (CO2 and NH3)
-Ureageneses
-Gluconeogenesis
“limiting AA”
AA that is in the shortest supply relative to reqs
-usually and indepsnible AAlt
-Lysine and Metanine *typically limiting
“spiky” sonic protein
first discovered in the fruit fly
has spiky look
provides information for embryos to develop
pivotal in separating your right brain from your left
make sure we have two individual eyes
Ranasmurfin
protein prdouced. by tree frogs that is blye
-foam produced by females to protect the eggs
Protein Catabolism
proteins are broken into amino acids by hydrolysis of their peptide bonds
deamination
removal of the amino group from and amino acid which creates an ammonia and an organic acid
-ammonia gets removed in urea
Animals that release ammonia
bony fishes and the larvae of amphibia
animals that release urea
many terrestrial vertebrates and ahsarks
animals that release uric acid
bird and reptiles
When was the discover and Isolation of Vitamins Discovered
1912
Where does the word vitamin come from
Vit-comes from the word vital and amine comes from when they thought amines made up vitamins
Polioencephalomalacia
Deficiency of Vitamin D1/thymine
What vitamin deficency causes rickets
Vitamin D
Scurvy
Vitamin C defiency
Symptoms of scurvy
-the structure of collagen is defective
-spongy gums, bleeding from mucous membranes
Functions of Vitamin C
-antioxidant
-synthesis of collagen
-synthesis of carnitine
-biosynthesis of norepinephrine
What are vitamins
-organic compounds required in small amounts
-cofactors in metabolic reactions
-donor or acceptor groups for metabolic intermediates
-enzyme precursors, coenzyme and antioxidants
Fat Soluble Vitamins
-Vitamins A, D, E, K
-Associated with fat during digestion and absorption
-storage in liver, adipose tissue and excess storage can be toxic for some vitamins
-no daily need
deficiency is very slow
Water-Soluble Vitamins
-total nine, all B vitamins and vitamin c
-Soluble in water and excess excreted through urine
-no storage and less toxic
-daily requirement(expect b12)
-serve as cofactor in biochemical reactions
-deficiency is fast
Vitamin A
-Discovered in 1922 as a “fat-soluble factor” present in butter and fish oil
-includes several related compounds
-retinol is the biologically active form of Vit A
Functions of Vitamin A
-vision
-bone-growth
-reporduction
-maintenance of epithelial cells
-antioxidant
Hypervitaminoses
varies with species, age and physiological condition. Results in skeletal abnormalities and thickening of skin
Vitamin D
-sterol compound
-regulates Ca and P metabolism
-formed by irradiation of sterols in plants and skin
-confined animals require vitamin D
-vitamin D3 needed for carnivores and omnivores
cats and vitamin D
-do not make vit D
-included in diet
-7-dehydrocholesterol is converted to cholesterol
1.25-dihydroxycholecalciferol
-steroid hormone acitivity
-regulates DNA transcription in microvilli
-synthesis of RNA-responsible for ca-binding protein
Vitamin E
-group of compounds called tocopherols and tocotrienols
-a-tocopherol most active biological form added to diets
Functions of Vitamin E
-antioxidant to protect cells from oxidative damage induced by free radicals
-prevents oxidation of lipids s
-lipid peroxidation causes damage to unsaturated lipids in cell membranes resulting in the disruption of the structural membrane and cell integrity
-peroxidation can reduce palatability and animal health
-protects proteins and VIt A
Deficiency of Vitamin E
-white muscle disease (degeneration of heart muscle)
-exudative diathesis in chickens( leaky capillaries in breast muscle)
-encephalomalacia (crazy chick disease)
Toxicity of Vitamin E
-least toxic of the fat-soluble vitamins
-high levels are added in diets of animals to enhance food nutritional value and lipid stability
Vitamin K
-Includes a group of compounds call quinones
-vit k1 found in plants
-Vit K2 synthesized by microbes
Menaquinone is the metabolically active form
Functions of Vitamin K
-synthesis of prothrombin blood-clotting protein
-Gi reacts microbes a good source of Vit K-abosrption or coprophagy
-mold growth on sweet clover hay or silage contains dicumarol, similar to Vit K in structure and competitive inhibitor
Water soluble vitamins
-no provitamins
-responsible primarily in energy transfer
-absorbed more easily and readily from SI
-water soluble vitamins are not stored to a great extent
-excretiom occurs both in feces and urine
-rumen microbes can synthesize all
Animal products vitamin content
rich in most vitamin including lipid soluble but deficient in Vit C
Microbial Fermentation VItamin Concentration
-supplies vit B12, K and biotin
-need other vitamins in diet
Concetrates VItamin Concentration
B vitamins
Functions of Minerals
-Constitute -4% of the animals body weight
-expression and regulation of genes and enzymes
-cellular function, osmotic balance, detoxification, immunity, acid-base balance and growth
-O2 transport requires Fe
-Thyroid hormone made using I
Macro minerals
required in large quantities in the diet (>0.01%)
Microminerals
required in trace amounts (<0.01%) in mg, ug or ppm
How are the minerals added in the diet
minerals cannot be added to a diet in their elemental forms but rather need to be added as salts that ar combined with other minerals (NaCl, CaCO3, MnSO4 etc..)
Calcium and phosphorus functions
-structural-growth and naintenance
-nervous and muscle contraction
What are some of calciums individual functions
-gorwth or maintence of bone mass
-blood coagulation, nerve impulse and cell permeability maintenance
-ezyme activation, muscle contraction and ion channels
How is phophorus involved in phosphorylation reactions
-ATP
-DNA and RNA contain phosphorylated pentose sugars
-Cell membrane phospholipids (cellular fluidity anf transport of nutrients)
Phosphorus features
P is present in the bound form as phylate or phytic acid
-the availability of P from bound sources varies (20%-60%)
-monogastric animals lack the enzyme phytase to release P from the bound form
-ruminant animals produce microbial phytase enzyme that can split and liberate phosphorus
Regulation of Blood Calcium Levels
-body has a strict homeostatic regulation-steady state blood plasma Ca
-Parathyroid hormone, calictocin ad activr formes of vitamin D
What happens in hypocalcemia
PTH is released from the parathyroid gland, increasing Ca and P resorption from bone, P excretion into urine and synthesis of active forms of vitamin d
-this in turn increases absorption of dietary Ca from the gastrointestinal (GI) tract
Ca:P ratio
1:1 small animals
2:1 large animals
-excess dietary Ca forms insoluble complexes with phosphorus resulting in decreased P absorption
-High P or phytate P in the diet can inhibit Ca absorption
When is excess P and low Ca common
in animals fed grain based or low quality hay diets
pets fed homeade meat-based diets
Ca & P deficiency or imbalance
-bone growth disorders eggshell quality in egg-laying hens
-Rickets is a condition occuring in young animals due to normal gowth in the organic matrix but insufficent mineralization
-osteomalacia occurs in adult animals (excessive loss of Ca causing brittle deminerlaized bones)
-In both rickets and osteomalacia bones become soft and often deformed due to improper calcification
Hypocalcemia
-tetany and convulsions-severe Ca defincency
-Milk fever or parturient paresis
-drop in body temperature,animal collapses with head bent over the flank
Hypocalcemia treatment
raise blood Ca through intravenous supply of Ca salts such as CaCl2, Ca-lactate or Ca gluconate
Magnesium
-presnet as phosphate and carbonate in bone and in liver and skeletal muscle cells
-strucural role in the skeletal system
-activation of enzymes in the cells
-metabolism of carb and proteins
important from muscle contraction and transmission of nerve impulses
Magnesium deficiency
-grass tetany
-affects livestock on lush green pastures of cereal forages of native pastures in the spring season
-N and K inhibit MG absorption
Magnesium Deficienncy symptoms
-muscle tetany, head retraction, staggering, convulsion and extreme senstitivity to noise or touch
Sodium
-common salt (NaCl) is added to the diets of all animals and is given free choice to grazing animals
-Na+ maintains cell permeability in the active transport of nutrients across membranes
-Na_+ pump controles electrolyte balance
-required for muscle contraction and nerve impulse transmission
Magnesium Deficency Treatment
-include intravenous injection of Mg solution, feeding Mg from different sources, pasture rotation and providing dry forages
Potassium
-major cation found in greater concentrations in intracellular fluid
-Ionizsed K+ inside cells provide osmotic force and maintains fluid volume
-cellular K+ is also involved in enzymatic reactions
-K+ balance important for normal heart muscle functions
Chlorine (Cl-)
-counterbalances the role of K+ and Na+
-also regulates osmostic pressure
-HCl, activation of gastric enzymes, protein digestion
-suppiled through NaCl in the animal diet
Dietary Electrolyte Balance in Food Animal Health and Production
-In ruminants, electrolyte balance is important in preventing acidosis and alkalosis
-DCAD reduces the incidence of milk fever
-prepartum alkalosis may increase the incedence of milk fever wheras acidosis may prevent it
-prepartum diets high in forages could reduce the ability of the cow to maintain Ca homeostasis and cause milk fever
-diets that reduce blood pH can increase blood Ca and reduce the milk fever
Chromium and Glucose
-Cr is part of a molecule ‘glucose tolerance factor’ & required for normal glucose entry into cells
-supplemented into piglet diets and pregnant sows to improve glucose utilization
-enhances milk production in lactating cows
