Macro + Micronutrients Flashcards
Nutrients
categories + general neeeds + function
Categories 🡢 water, carbs, proteins, fats, minerals, vitamins
Relative needs:
- 2/3 part water + 1/3 DM 🡢 energy wielding = 50-80% of DM
- proteins + fats 🡢 variable
- minerals 🡢 2-3%
- vitamins 🡢 0.2-0.3%
Functions:
- energy supply
- structural components
- temp control
- for chemical reactions
- transport of substances
Water
Sources, Function, Requirement
Sources 🡢 ingested (env.) + metabolic
- metabolic 🡢 10-16ml/100kcal of ME & 5-10% of water requirment
40-80% of total body mass
- Lean = more body water vs. obese = less body water
- water requirements lower with age
10% water loss 🡢 illness
15-20% water loss 🡢 death within days
Functions:
- solvent 🡢 transport of substances
- chemical reactions 🡢 hydrolysis
- thermoregulation
- structural 🡢 shape + constituent of body fluids
Water intake 🡢 dry foods v moist/wet food
Water loss 🡢 urination. defacation, evaporation, perspiration
daily water req. (mL/day) ~ daily energy req. (kCal/day)
Water intoxication 🡢 hemodilution, hyponatremia, edema in brain
cats form more concentrated urine than dogs
Quality of Water
Total Dissolved Solids (TDS) 🡢 general indicator of quality of water
- < 5000 ppm TDS acceptable for livetsock
- < 500 ppm TDS acceptable for humans + pets
- > 7000 ppm TDS not acceptable
Factors affecting quality:
- mineral content 🡢 less concerns in domestics
- nitrates/nitrites 🡢 toxic in dogs + cats
- bacterial contamination
Carbohydrates
Types, Requirement, Uses
Types:
- monosaccharides 🡢 trioses, pentoses, hexoses
- disaccharides 🡢 lactose (mammals), sucrose (plants)
- oligosaccharides
- polysacchardies 🡢 digestibles starches (plants) + glycogen (animals) v nondigestible fibers
no absolute dietary requirement
needs vary over time 🡢 growth, gestation, lactation
glucose needed in body to maintain TCA cycle + energy source for CNS + blood cells
Carbohydrates
Digestion + Metabolism + Excretion
Digestion:
- dogs + cats lact salivary a-amylase
- primarily digested in SI by pancreatic amylase + enzymes in brush border of intestinal mucosa (maltase, sucrase, lactase)
- gelitinization of starches 🡩 digestibility 🡢 30-35% of DM in commercial pet foods
Metabolism:
- glycolysis + TCA cycle
- provide chemical energy 🡢ATP or GTP
- metabolic byproducts 🡢 non-essential AA, glycoproteins, lactose, vitamin C
- endogenous energy stores 🡢 glycogen, fat
Excretion:
- 6CO2 + 6H20 + heat (aerobic)
- flatus 🡢 bacterial fermentation
Animals with deranged carb metabolism 🡢 elevated plasma or urine of sugars + metabolites
- DM 🡢 high glucose + ketones
Unabsorbed carbs in lumen:
- high osmotic pressure 🡢 reduces water + mineral absorption
- abdominal distension + diarrhea
- bacterial overgrowth
- overproduction of gas d/t bacterial fermentation
Carbs of special importance in Vet Med
Xylose 🡢 used in dogs to test absorption
Lactulose 🡢 prebiotics + laxative
Glycosaminoglycans 🡢 dietary supplements for joints
Oligosaccharides 🡢 prebiotics
Resistant Starches 🡢 dietary fibers (can help with glycemix index + improve bowel health)
excess fiber can 🡣 nutrient index + 🡣 mineral absorption
Proteins + Amino Acids
Types, Requirements, Uses, Considerations
Amino acids = carboxyl (COOH) + a-amino (NH2) + 20 AA
Peptide bonds 🡢 dipeptides, tripeptides, polypetides
Essential v non-essential AA
- glutamine is the only conditinally essential AA
Requirements 🡢 specific requirements based on individual
- Dogs : puppy = 18% v adult = 8% of DM
- Cats : kitten = 18% v adult = 16% pf DM
Amino Acids needed for:
- structural components 🡢 collegens, elastins, keratins
- functional units 🡢 muscle, enzymes, immunoglobulins, protein hormones, etc.
- precursors 🡢 nitrogen, energy
Considerations
- amount of food consumed 🡢 meet specific energy requirements 🡢 small amount / high protein + calory v large amount / low protein + calorie)
- maintenence protein requirement 🡢 dietary protein that must be consumbed to replace obligatory N loss
- imbalance 🡢 1+ aa needed but not available but at least another aa is provided in excess
- antagonism 🡢 aa with similar chemical structure
Protein Quality
- refers to efficiency of converting aa 🡢 tissues
- dependent on source, concentration + availability of essential aa
High v Low Quality
- protein sources with optimal proportions of ALL essential AA
- protein sources that lack 1+ essential essential AA
- imabalance +/- antagonism of AA 🡢 lower protein quality
- processing 🡢 lower digestibility 🡢 lower quality protein
- animals v plant sources
Improving quality:
- proteins complementation 🡢 combining protein sources
- aa supplementation
Protein + Amino Acids
Digestion, Absorption, Metabolism, Storage, Excretion
involves chemical + enzymatic digestion
Digestive tract:
- stomach 🡢 pepsin + HCl 🡢 large polypeptides
- SI 🡢 peptidases
Fate of AA:
- tissue protein synthesis 🡢 actin, myosin, hormone receptors, etc.
- biosynthetic pathway
- deamination 🡢 carbon skeleton 🡢 energy
Storage:
- not stored to same degree as sugars + fats
- muscle + liver protein + serum albumin
Excretion:
- AA catabolism produces N waste 🡢 if not used for purines + pyramidines
- NH3 🡢 urea (via urea cycle) 🡢 urine excretion
Unabosrbed AA or small peptides
- substrate for bacterial fermentation
- 🡩 fecal odor
Amino Acids of Special Importance in Vet Med
Taurine 🡢 essential for cats / non-essential for dogs
- not incorporated in protein 🡢 free AA in animal tissue
Functions:
- aids in absorption of dietary fats 🡢 cats only conjugate taurine to bile acid
- NT + neuromodulator in CNS 🡢 body temp control + brain dev.
- heart + retina maintence 🡢 deficiency linked to central retinal degeneration + DCM
- repro
Arginine 🡢 essential in domestics
- key intermediate in urea cycle 🡢 detoxifies N waste
- cats sensitive to deficiency
Glutamine/Glutamate 🡢 conditionally essential in domestics
- key role in 🡢 TCA cycle, generation of NADPH + GABA, antioxidant glutathione
Minerals
Requirements, Uses, Considerations, Absorption
- inorganic elements of food
Macrominerals : % VS microminerals (trace) : ppm
- ~ 18 essential elements 🡢 7 macros + 11 trace
General requirement 🡢 2-3% of DM
Uses:
- structural components of organs + tissues 🡢 Ca, P, Mg
- constituents of body fluids (electrolytes) 🡢 osmotic pressure, AB balance, muscle contraction
- reaction catalysts/co-factor 🡢 enzymes, proteins
Considerations:
- excess or defficiencies
- needs vary over time 🡢 demographic, homeostatic mechanisms
- dietary components 🡢 dietary fibers interfere with absorption of minerals
- mineral interactions 🡢 synergistic v antagonistic
antagonistic minerals:
- share same tranpsport channels
- interfering with storage
- competing for transport protein
Absorption:
- intestinal mucosa 🡢 transporter system = transcellular + paracellular
Factors Influencing Mineral Availability
1) Chemical form 🡢 influences solubility
- organic > inorganic forms
- meat-derived > plant-derived
- sulfate/chloride form > carbonates > oxides
2) amount/proportions of other dietary components 🡢 antagonistic interactions
3) age, gender, species
4) intake of mineral + need
5) env. factors 🡢 presence of non-nutritional factors
Calcium
Function, Deficiency, Excess
Major Functions:
- bones
- muscle function
- nerve conduction
Deficiency:
- 🡣 in growth, appetite, bone mineralization
- tetany
- convulsions
Excess:
- 🡣 feed efficiency
- urinary calculi
Phosphorus
Function, Deficiency, Excess
Major Function:
- bones
- nucleic acids
- phospholipids
- metabolism of sugars, proteins, fats
Deficiency:
- pica
- 🡣 in growth, apetite, bone mineraization
Excess:
- calcification of soft tissues
- urinary calculi
Potassium
Function, Deficiency, Excess
most abundant IC cation
Major Functions:
- muscle contractions
- nerve conduction
- AB balance
- osmotic pressure
Deficiency:
- locomotive problems
- muscle weakness
- heart failure
Excess:
- paresis
- bradycardia
Sodium + Chloride
Function, Deficiency, Excess
most abundant EC cation + anion
Major Functions:
- osmotic pressure
- AB balance
- nerve conduction
- muscle contraction
- nutrient absorption
Deficiency:
- water imbalance
- fatigue
- anorexia
Excess:
- thirst
- constipation
- seizures
Magnesium
Function, Deficiency, Excess
Major Functions:
- component of bones
- component of ICF
- NM transmission
- enzyme function
Deficiency:
- retarded growth
- 🡣 bone mineralization
- muscle weakness
- tetany
- convulsions
- anorexia
- vomiting
Excess
- bladder stones
- flaccid paralysis
Iron
Function, Deficiency, Excess
Major Functions:
- oxygen transport
Deficiency:
- anemia
Excess:
- hepatic dysfunction
- hemosiderosis
Iodine
Function, Deficiency, Excess
Major Functions:
- T3 + T4
Deficiency:
- goiter (enlarged thyroid)
- lethargy
Excess:
- goiter
- fever
Zinc
Function, Deficiency, Excess
Major functions:
- constituent/activator of >200 metabolic enzymes
- nucleic acid/carb metabolism
- protein synthesis
- growth
- repro
Deficiency:
- 🡣 growth
- impaired repro
- anorexia
Excess: (relatively non-toxic)
- vomit
- diarrhea
- 🡣 appetite
Grass tetany
aka grass staggers
Horses + Ruminants
rapidly growing grasses tend to be RICH in K + very LOW in Mg/Ca
clinical signs thought to be d/t low Mg 🡢 Mg supplement is mainstay of treatment
Big Head
aka Nutrtional Secondary Hyperparathyroidism
excessive bran in diet 🡢 high in K, low in Ca
low levels of serum calcium stimulate PTH 🡢 induces osteoclast-mediated resorption of bone
bone replaced by copious fibrous tissue
Goiter
domestics
most commonly d/t iodine defficiency
- low iodine in diet
- ingestion of goitrogenic substance
insufficient iodine 🡣 ability of thyroid to make hormones
with 🡣 circulating TH, pituitary secretes more TSH
causes hyperpplasia of TG 🡢 development of goiter
goiter is not synonymous with hypothyroidism
Hemosiderosis
anemia is common in newborn piglets d/t
- low iron reserve
- low iron in colustrum
- insufficient contact with dirt
why piglets get iron injections
Copper Storage Disease
hepathopathy of bedlington terriers 🡢 30-60% affected
caused by mutation in COMMD1 gene that affects copper excretion in liver
Copper Toxicity
many factors that alter Copper metabolism influence chronic copper poisoning by 🡩 absorption/retention of copper
Ex. 🡢 low levels of molybdenum or sulfate in diet
toxicosis remains subclinical until copper is stored in liver is released in massive amounts
blood [copper] 🡩 suddenly 🡢 lipid peroxidation + intravascular hemolysis
sheep most sensitive
Vitamins
Defined by physical + physiologic characteristics:
1) organic substances that aren’t lipis, CHOs, proteins
2) dietary component
3) essential for normal phys. function
4) not produced in sufficient quantities to support phys. function
5) deficiency syndrome
not all vitamins are essential for all species
Vitamers 🡢 chemically same/related compound as vitamin, may exert diff. effect
Provitamin 🡢 vitamin precursor that requires activation
classification 🡢 water-soluble v fat-soluble
Requirements 🡢 0.2-0.3% of DM
Needs in body:
- enzymes co-factors 🡢 B
- roles in DNA synthesis 🡢 folic acid, B12
- metabolism of nutrients 🡢 B
- bone dev. + calcium homeostasis 🡢 D
- eye function 🡢 A
- cell membrane integrity 🡢 E
- blood clotting 🡢 K
- free radical scavenging 🡢 C, E
- nerve impulse transduction 🡢 B
Considerations:
- excess of deficiences 🡢 species differences
- storage of vitamins 🡢 fat-soluble in lipid depots v water soluble has limited storage
- needs vary over time
Factors Affecting Availability:
- disease
- drugs
abx 🡢 decrease Vitamin K
Vitamin Interactions
One needed for optimal absorption of another
- B6 for B12
- folate for thiamin
One may interfere with absorption/metabolism of another
- E with K
- B6 with niacin
- thiamin with riboflavin
One needed for metabolism of another
- riboflavin for B6 + niacin
- B6 for niacin
One protects against excess catabolism, urinary loss or oxidative destruction of another
- C spares B6
- E spares A
- C spares E
High level of one can obscure diagnosis of deficiency of another
- Folate deficiency obscures B12 deficiency
Vitamin A
Major Functions:
- component of visual proteins
- spermatogenesis
- bone resorption
- immune function
Deficiency:
- xerophthalmia 🡢 dry conjuctiva
- nyctalopia 🡢 night blindness
- aspermatogenesis 🡢 lack of sperms
- retarded growth
Excess:
- cervical spondylosis (cats)
- slow growth
- anorexia
Vitamin D
Major functions:
- Ca + P homeostasis
- bone mineralization
- insulin synthesis
Deficiency:
- rickets
- osteoporosis
Excess:
- hypercalemia
Vitamin E
Major Function:
- antioxidant
- free radical scavenger
Deficiency:
- sterility (males)
- myopathy
Excess:
- impaired bone mineralization
- 🡩 clotting time
retained placenta per cara
Vitamin K
Major functions:
- clotting factor
Deficiency:
- prolonged clotting time
- hemorrhage
Excess:
- minimal toxicity
B-Complex Vitamins
Function:
- nutrient metabolism
- co-enzymes/co-factors
- purine + DNA synthesis
Deficiency:
- anorexia
- retarded growth
- weight loss
Excess:
- low toxicity
Vitamin C
Major function:
- enzyme co-factor
- collagen synthesis
- antioxidant
Deficiency:
- NONE 🡢 domestics synthesize their own
Excess:
- NONE in domestics
Choline
vitamine-like + conditionally essential
Major Function:
- precursos to acetylcholine + phosphatidylcholine
Deficiency:
- 🡣 growth rate
- fatty liver (puppies)
Excess:
- NONE in domestics
L-carnitine
vitamin-like + conditionally essential
Major functions:
- transports FA to mitochondria
Deficiencies:
- hyperlipidemia
- cardiomyopathy
Excess:
- NONE in domestics
Scurvy
Vitamin C deficiency 🡢 primates + guinea pigs
- other domestics synthesize it
C needed for hydroxylatin of lysine + proline in regards to collagen synthesis
Result 🡢 multitude of effects d/t 🡣 collagen synthesis capabilities
Rickets
Vitamin D deficiency 🡢 any species but mostly swine + poultry
wide variety of clinical signs:
- failure of both vascular invasion + mineralizaton in area of provisional calcification of physis
- pathology is most obvious in metaphyses of long bones 🡢 proliferative zone enlarged
Metastatic Mineralization
Vitamin D excess 🡢 usually d/t ingestion of cholicalciferol-based rodenticides
deposition of calcium salts in otherwise normal tissue
result 🡢 raise calcium
- when serum calcium + phosphate product is > 70mg2/dl2 = mineralization can occur
Vitamin K Depletion
d/t anticoagulant rodenticides
clotting factors 2,7,9,10 are vit. K dependent
depletion 🡢 inability to clot = hemorraghes
Polioencephalomalacia (PEM)
vitamin B1 (thiamine) deficiency 🡢 any species but mostly ruminants + cats
vitamin B1 intimately involved in metabolism + energy maintenence
neurons are one of most energy-intensive cells 🡢 first to fall in an energy deficit
- Result 🡢 death of neuronal cell bodies
usually not d/t diet defficiency but rather ingestion of thiaminases 🡢 degrade extant thiamine
Ruminans 🡢 bracken fern, horsetail, some bacterial species
Cats 🡢 fish + some shellfish diet exclusive diet can lead to PEM
