Lecture quiz 4/12/23 (wednesday) Flashcards
What are fats?
- fats ( glycerides) are a subclass of LIPIDS
= compounds that are insoluble in water but soluble in organic solvents (ether)
What are the several subclasses of lipids?
- glycerides, phospholipids, glycolipids, lipoproteins, etc.
What class has the greatest significance in nutrition?
Lipids
Lipid class of greatest significance in nutrition (for us) are the glycerides including mostly triglycerides, but also some diglycerides and monoglycerides
Do all glycerides have a glycerol backbone?
yes
mono - 1 fatty acid
di - 2 fatty acids
tri - 3 fatty acids that are attached (triglycerides)
what is the more formally names version of glycerides?
acyglycerols
What does R stand for?
fatty acid
what is the nature of fat?
it depends on what fatty acids are connected to the glycerol molecule
What are fats composed of?
CHO but little oxygen in relation to carbon and hydrogen
- they are highly digestible
how much more energy does fat yield compared to carbohydrates and protein?
2.25 times more
what are saturated fats?
no double bond
what are unsaturated fattss?
double bonds
What are the building blocks of fat?
fatty acids
what are VFAs?
VFA - volatile fatty acids = produced from microbial fermentation of carbohydrates in the rumen and hindgut fermentation
- Acetic acid = 2 carbons - CH3COOH
- Propionic acid = 3 carbons - CH3CH2COOH
- Butyric acid = 4 carbons - CH3CH2CH2COOH
What are the short-chain fatty acids?
acetic
propionic
butyric
What are the long-chain saturated fatty acids?
palmitic acid- 16 carbons = 16:0
stearic acid - 18 carbons = 18:0
what is an example of a long-chained unsaturated fatty acid that is not essential?
Oleic Acid (18:1)
- found in olive oil, animal fat, wagyu
what are examples of essential long-chained unsaturated fatty acids?
- Linoleic acid - 18 carbon 2 double bonds (18:2)
- Linolenic - 18 carbon 3 double bonds (18:3)
- Arachidonic acid - 20 carbons 4 double bonds ( Essential only for cats) = 20:4
Where can we find glucose in freeform?
can be found in foodstuff
- fruits
- refined carbohydrates = corn syrup
honey
What do we mean by the major end product of CHO digestion for non-ruminants?
non ruminants (humans or omnivores)
- swine and poultry (monogastric) = final end product glucose = the main form of carbs is starch from grains and tiny fiber + some sucrose ++ main energy source GLUCOSE
Ruminants and hindgut fermentors = VFA (acetic, propionic and butyric acids) (MAIN ENERGY SOURCE) by microbes== NOT GLUCOSE
Since mammalian and avian enzymes cannot break beta bonds there is an exception. What is the exception in disaccharides?
Lactose = galactose and glucose (ß1,4 glycosidic linkage)
What is the main source of carbohydrates in swine and poultry?
CHO in grains in swine and poultry are mainly from starch but they also consume fiber
What is the main source of carbohydrates in hindgut fermentors and ruminants
- CHO in forages
- mainly in the form of cellulose and hemicellulose
- they can consume some grains (starch) when they need to get chunky to reach nutrient requirements
cattle to grow fast - give grains to get marbled fat and more energy + high carcass value
digestibility of starch is higher than fiber
non structural vs structural CHO
cell wall fraction (hemicellulose, cellulose and lignin)
hemicellulose and cellulose = structural CHO
Non structural CARBS
starch = from seeds not part of the cell wall + inside the cells + sugars too
Sugars - mono and di
What will happen if you give too much starch to horses
too much in horses = colic and laminitis
- high blood glucose = increase resistance
- mess up the hind gut and lower pH -
feed is always check for nonstructural carbs even in forages
ALWAYS WATCH FOR THE NON STRUCTURAL CARBS
