Animal Nutrition Quiz 5

what are fats/lipids soluble in

organic solvent

what are the 3 classes of lipids

simple, compound, sterols

do plants & animals synthesize even or odd-numbered FA

even

how would a ruminant animal be able to acquire odd-numbered FA

through the bacteria present in rumen

what is stored in the body; FFA or triglycerides

triglycerides

what is an example of a simple lipid

vegetable oil and animal fat

What is an example of a compound lipid

glycolipids, lipoprotein, phospholipids

what is an example of a sterol

cholesterol, estrogen, testosterone

what do FA do for lipid nutrition

structure, composition, metabolizability

what makes up a triglyceride

one glycerol, three fatty acids, connected by ester bonds

what is the name of the reaction that combines glycerol and fatty acids to form a triglyceride

esterification

what is the primary form of lipid storage in animals

fat

what is the primary form of lipid storage in plants

oil

when is fat stored

excess of energy in diet

when is fat broken down

negative energy balance

classes of fatty acids

saturated and unsaturated

difference between saturated and unsaturated fatty acids

saturated has no double bonds, unsaturated has one or more

are saturated fatty acids primarily solid or liquid

solid ex. butter

difference between cis and trans fatty acids

cis has the H atom present in the same plane, trans are on two different planes

will cis bonds be liquid or solid at room temp, why, example

liquid, there is a kink that stops the FA from packing tightly, ex. vegetable oil

what is the difference between n-3 and n-6

the position of the first double bond

which has the lower melting point: short or long chain FA

Short

which has the higher melting point: saturated or unsaturated FA

saturated FA

examples of essential FA

linoleic, linolenic, arachidonic

why are fats important in the animals body

major source of energy

3 functions of fats in animals

energy, insulation, parts of cell memebrane

what are the two steps of lipid digestion 

emulsification, enzymatic

what are the major organs in lipid digestion (monogastrics)

stomach, small intestine

which enzyme is responsible for lipid digestion in the stomach

gastric lipase

why is lipid digestion limited in the stomach

low pH

which organ is the major site of lipid digestion in a mature animal

small intestine

where are bile slats produced and stored? 

produced in the liver, stored in gallbladder

what is the role of bile salts in digestion of fats/lipids

they can attract both fats and water, start of emulsification

which enzyme is responsible for the digestion of triglycerides in the small intestine

pancreatic lipases

what are the end-products of enzymatic digestion in the small intestine

2 free fatty acids, 1 monoglyceride

what is the purpose of micelle formation in the small intestine

transport products to brush border

what makes up micelles

bile salts, fatty acids, monoglycerides, vitamins and chloesterol

what products of fat digestion are absorbed by simple diffusion

FA, monoglycerides, glycerol, cholesterol, fat soluble vitamins

what happens to the bile salt once the fat compounds enter the enterocytes

recycled to help with emulsification of fat and forming micelles

what happens to the short chain FA in the enterocyte

directly absorbed into bloodstream

what happens to the long chain FA in the enterocyte

need help to be absorbed and transported to the bloodstream

what happens to the long chain FA & monoglycerides

made into triglycerides

what happens to the cholesterol & fat soluble vitamins

put into chylomicrons

what is the purpose of chylomicrons

transport vehicles for lipids to the lymphatic system to the bloodstream

which circulatory system do chylomicrons enter first

lymphatic system

what happens with the profile of FA in swine carcasses when we feed pigs with a finishing diet rich in sources of unsaturated FA

the carcass will be rich in unsaturated FA, be soft and excrete liquid, more prone to oxidation and soft bellies

major difference in chylomicron absorption between pigs and chickens

absorbed into bloodstream then to liver and transported/ distributed to body

which enzymes is more active in newborn animals and why

gastric lipase, because of low pH and the body is naive

how do neonatal animals digest fats in their diet

colostrum & milk contains lipases

what are the end-products of the hydrolysis of triglycerides in the rumen

glycerol and free fatty acids

after triglycerides are hydrolyzed what happens with glycerol

fermented into propionate to glucose in the liver

what are the end-products of the hydrolysis of glycolipids in the rumen

glycerol, FFA, CHO

after glycolipids are hydrolyzed what happens with glycerol & CHO

propionate and energy

what happens with unsaturated FA in the rumen

biohydrogenation

adding of H atoms to unsaturated FA, H atoms replace double bonds, FA becomes saturated

what is biohydrogenation

why unsaturated FA need to be biohydrogenated

unsaturated FA are toxic, digestion is reduced

the majority of the FFA leaving the rumen enters the abomasum as (blank) FA

saturated

why is fat deposition in ruminants not the same as what they est

biohydrogenation

what cause milk fat depression

conjugated linoleic

what happens with saturated FA in the rumen

dont undergo biohydrogenation, pass through rumen unaltered

what types of fats/FA can be used in ruminants diets

unsaturated, saturated, rumen protected fat

what are examples of rumen protected fat

calcium soap, prilled fat

pass to the abomasum unchanged, low pH make fat available to enter SI, benefits energy density without negative effects on rumen, fermentation and doesnt have milk fat depression

benefits of using rumen protected fat

when more energy is consumed what are the fates of lipids

stored in body as fat

when the animal is in negative energy balance with are the major fates

oxidized for energy

what is lipogenesis

synthesis of FA from non-lipid sources

what are the two key enzymes for lipogensis

acetyl-CoA carboxylase, Fatty acid synthetase

what are the steps of de novo

fatty acid synthesis, elongation, desaturation, esterification

what are the major precursors for fat synthesis in ruminants

acetate and BHBA

what are the two steps of lipid degradation

lipolysis, B-oxidation

what are the end products of lipolysis

glycerol, FFA

which enzymes plays a key role in lipolysis

hormone-sensitive lipase

what is the major goal of B-oxidation

ATP production