Macro + Micronutrients Flashcards
(44 cards)
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
