Lipids

Functions of Lipids

• ENERGY STORAGE

• Fatty Acid Source

• Fat soluble vitamins transport

• Constituent of cell membranes

Carbohydrates vs Lipids in Energy Storage

-Carbs have limited storage capacity

-Lipids have UNLIMITED storage capacity.

Kcal Comparison of Carb vs Lipid

Lipids=more concentrated energy (5 kcal more per gram)

1gram of lipids contain 9 kcal

1 gram of carbs contain 4 kcal

Composition of Lipids

Organic compounds, insoluble in water (oil in water)

Fatty Acid

Type of Lipid

has a carboxyl group in the acid part and soluble in water but not fat,

Fatty part is soluble in fat not water, 2-22 carbon chains

Saturated Fatty Acids in regards to nutrition

-Saturated with hydrogen atoms but have no double bonds between carbon atoms only oxygen

-From Animals

-Examples are solid at room temp items like: butter, lard, cheese, fatty cuts of meat

-Limit the intake of saturated fat to not raise cholesterol.

-They provide energy and help with absorption of fat-soluble vitamins (A,D,E,K)

Unsaturated Fatty Acid

-Usually liquid at room temp and have 1 or more bonds between carbon atoms

-From Plants and fish

-Considered healthier than saturated fats.

-Lowers cholesterol, reduce inflammation, support brain function…

Two types of Unsaturated Fatty Acids

1. Monounsaturated Fatty Acids (MUFA)

   1. Found in Olive oil, avacodos, nuts(peanuts, almonds, cashews

2. Polynusaturated Fatty Acic

   1. Ommega-3 and Omega-6 fatty acids

   2. Found in Fish, Flaxseed, Walnuts, Sunflower oil.

Saturated Fatty Acid Chain

-No double binds to carbon

Unsaturated Fatty Acid

-Double carbon Bond

Saturated fatty Acid

-Neat figure

Unsaturated Fatty Acid

-Not neat or uniform

Cis or Trans double bonds

Nomeclature and example

Dependent on the number of carbon and number of double bonds

C2:0

C2 shows the number of Carbon 2 and

0 stands for no double bond between the carbon

Essential Fatty Acids for animals Diets

Linoleic ( C18:2)= 18 Carbon with 2 double bonded

-Omega 3

Linolenic Acid (C18:3)= 18 Carbon with 3 double bonds

Omega 6

Omega 3

Poly-Unsaturated Fatty Acid

3 carbon counted from the end of the chain

Linoleic ( C18:2)= 18 Carbon with 2 double bonded

Omega 6

Poly-Unsaturated Fatty Acid

6 carbon counted from end of chain

-Linolenic Acid (C18:3)= 18 Carbon with 3 double bonds

Three Types of Simple Fatty Acids

1. Saturated Fatty Acid

2. MonoUnsaturated Fatty Acid

3. PolyUnsaturated Fatty Acid

Nomenclature Practice

C10:0

Capric Acid

Nomenclatire Practice

C18:2

Linoleic Acid

What are short-chain fatty acids synthezixed by microbes?

Volatile Fatty acids ( VFA’s) located

In reticulum in rumen

In hindgut in nonruminants

Acetate/ Acetic Acid (C2:0)

Producet of microbial digestion of fiber

Example: Vinegar (produced by the bacterial fermentation of corn.

Propionate/ Propionic Acid (C3:0)

Product of microbial digestion of starches and sugars

Example: Swiss Cheese

Butyrate/Butyric Acid (C4:0)

Produced in small amounts- sugar/Starch and fiber

Example: Butter

Complex Fatty Acids

They are attached to glycerol ( 3 carbond with a hydroxyl on each)

Types of Complex Fatty Acids

1. MONOglyceid

   1. 1 fatty acid attached

2. DIglyceride

   1. 2 fatty acids attached

3. TRIglyceride

   1. 3 fatty acids attached

Triglycerides

Most common in diet

Animal vs Plant Triglyceride Saturation

Animals: 50% saturated

Plants: 15% saturated

Which species has the higest amount of saturated fats?

Red Meat from rumenants, followed by swine, poulty, the some fish

Glycolipids

Carbohydrates+ Lipids

(On membrade of red blood cells)

Lipoproteins

Lipids+Proteins

-Allows lipids to be transported in bloodstream

Phospholipids

Phosporous+Fatty Acid

-Components of cell membranes

Cholesterol

-Animals Synthesize from Acetyl CoA

-Released from oxidation of fatty acids

-Can be used to make vitamin D and steroid hormones

Function of Lipoproteins

Transport lipids in blood

LDL

Low Density Lipoproteins

LDL info

-Bad Cholesterol

-Transports cholesterol to cells, including artery walls

• Plaques on artery wall

HDL

High Density Lipoproteins

HDL info

-Good Cholesterol

-Remove lipids from cells (including artery wall)

• Transports lipids to liver for use or excretion

Diets high in saturated fats lead to

Increase in serum cholesterol

Increase in low density lipoprotein

-Increased risk of atherosclerosis

Hyperlipidemia

high levels of Cholesterol and Triglycerides

-More common in dogs than cats

-effects carnivores eating fatty meals and getting to be overweight

How are lipids digested in MONOGASTRIC animals?

In the small intestine

-Aided by bile and pancreatic lipase

How bile works in digestion

Bile produced by liver (some store in gallbladder) emulsifies lipids and breaks them down which increases surface area. The smaller blobs are called micelles

-Balsamic vinaigrette

Pancreatic Lipase

Produced by Pancreases, hydrolyzes triglycerides (breaks down into monoglyceride and 2 fatty acids)

Depiction of the pancreatic lipase breakdown of triglyceride into monoglyceride and 2 fatty acids

Monogastric Digestability

-Lipids are highly digestible: can be influenced by

• Length of chain

  • >18 Carbon means lower density

  • Greater saturation=lower digestibility

Items with good digestibility/ absorption

1. Soybean oil 96% high low saturation (plant)

2. Corn Oil 94%

3. Lard 92%

4. Beef Tallow 70% (low saturation, fatty/saturated)

Fat Soluble Vitamins that Lipids help absorb

A, D, E, K

Primary Site of Absorption in Monogastric

Small intestine

Lipids broken by emulsion into micelles use simple diffusion into call lining in Small intestines

-Packaged as triglycerides and form chylomicrons

-Transported via lymph and bloodstream

Non-Lipemic: Dog serum after fasting several hours

Lipemic: Dog serum after eating puppy meal

Ruminant Lipid Digestion

Location: Rumen

Digested by:

Microbes that split fatty acids from glycerol backbone.

-Hydrogenation of unsaturated fatty acids of saturated fatty acid

Lipid Absorption

Location in Ruminants: Rumen

-Mineral absorption of larger fatty acids located in Rumenen—> Small intestine

-Large amounts can cause dietarty upset

Dairy farmer has decreasing fat levels in milk and thinning cattle. He tries to fix it by supplementing corn oil. What is the problem

The supplement has large amounts of unsaturated fatty acids and it harms cellulolytic bacteria.

-Limits VFA production (especially acetate.)

Lipid Metabolism

-VFAS transported in bloodstream

-Acetate and Butyrate→ Oxidized in tissues or used for fatty acid synthesis

Propionate→ Glucose

Butyrate→ Ketones

What hormones control storage and Degredation of fatty acids?

Insulin ( Fed state and fatty acids are stored)

Glucagon (Fasting State, FA are used as Fuel)

Ketone Bodies

Fasting or starvation

-Catabolism in liver→ Ketone Bodies→ Acetyl COA→ ATP

-Transported in blood,

-main fuel for brain and skeletal muscle during starvation

Ketosis

Problems occur with excessive ketone production because keotones are acidic

-Decrease blood PH

-Major issue in Ruminants

Why moghy a cow, goat or sheep require so much energy that ketosis occurs?

Pregnancy

-High nutrient demand in late stages and high demand in lactation

-Stress of birth

-Hormonal changes

Signs of Ketosis

1.Decrease feed intake

2.Decreased milk production

3. Cant stand→ Coma and death

How to prevent ketosis?

Feed adequate energy to pregnant animals, especially late in gestation.

Esssential fatty acids animals cant make?

Alpha-Linolenic acid (Omega 3)

Linoleic acid (Omega 6)

Composition of body fat

Animals that eat higher oils have softer carcass fat with lower melting points

Fish oil can change the taste of meat