Lipids and Fatty Acidspages 293, 294, 298, 299, 300additional pages may be sited.

Functions of fat:

•Provide the body’s primary form of stored energy• make up cell membrane structure• protects vital organs• aids in the transmission of nerve impulses• make things taste YUMMY

Lipids and Fatty Acids

• Lipids that are solid at room temperature are referred to as fats and lipids that are liquid at room temperature are referred to as oils.

Simple Lipids

• Simple lipids are Dietary fats made up of units called triglycerides (3 fatty acids held together by a molecule of glycerol).

• Fat is digested in the stomach and the intestines to smaller compounds. These compounds are repacked into structures called chylomicrons. These are transported to the bloodstream where they are later broken down by the liver.

Fatty Acids : page 298

• Saturated: have no double bonds in the primary hydrocarbon chain

• Monounsaturated: has one double bond

• Polyunsaturated: has more than one double bond

Are named according to the position of the first double bond. There are several families of fatty acids.

• Saturated fatty acids are more common in animal fat and less common in vegetable oil.

• As saturation increases, fats become less solid and more liquid at room temperature.

The length of the carbon chain backbone is used to classify

fatty acids. Short chain have 2 – 6 carbon

atomsMedium chain have 8 – 12

carbon atomsLong chain have greater than

14 – 24 carbon atoms.

Short chain are building blocks

Medium chain are found in mothers’ milk and certain foods such as coconuts. They are thought to be more easily broken down and absorbed

Long chain are the most common type found in foods. More palatable than medium chain.

Omega 3 and Omega 6This refers to the area of the

“backbone” where the first double bond is present.

The differences in structure result in different effects within the body.

Omega 3 – alpha-linolenic acid•Reduce inflammation• cognitive function• visual acuity• reduces chances of CHF and cancer

Symptoms of omega-3 fatty acid deficiency include fatigue, poor brain function, dry skin, heart problems, mood swings or depression, and poor circulation.

Omega 6 - linoleic acidconverted to arachidonic acid in the dog.

AA found in animal tissue but not plant material, which is why felines should not be fed a vegetarian

diet

•stimulate skin and hair growth• maintain bone health•regulate metabolism•maintain the reproductive system.

•Primarily found in nuts and seeds and vegetable oil

Omega 6 breaks down into AA.

Omega 3

Arachidonic Acid:

Is the precursor to a group of fatty acids that perform extensive hormonelike actions.

•vasoconstriction/vasodialation• muscle contraction• blood pressure homeostasis• regulation of body temperature• regulation of blood clotting• control of inflammation

Fatty Acids

• Essential fatty acids play an important role in kidney and reproductive function, cell membrane formation, and prostaglandin production.

• Signs of deficiency include: alopecia, dull hair coat, anemia, and hepatic lipidosis (fatty liver).

Fats – a review

• Fats are derived from animal and vegetable fats. Just as protein is composed of amino acids as their building blocks, fats are composed of fatty acids as their building blocks.

• 1 gram of fat = 9 calories of energy• Fats provide more calories• Fats make food taste better (palatable) and provide

better texture• Fats are essential for the absorption of certain

vitamins, such as A, D, E and K

Fat Influences

• Appetite and food intake• The dietary levels of minerals, vitamins,

and protein necessary to provide adequate nutrition

• The ability to perform muscular work• Hair coat condition• Type of fat deposited in the body• Tissue pathology

Technician Note

• Fats serve as primary sources of energy, supply essential fatty acids, facilitate digestion, and act as carriers for the fat-soluble vitamins (A, D, E, and K).

Fat Facts

• Fats are water insoluble• Mammals cannot synthesize essential fatty

acids; therefore fatty acids must be obtained from food.

• Fats, carbs and proteins are stored as fat when fed in excess of requirement

• Fat is catabolized when the body needs energy

Ketosis• Primarily occurs in animals with diabetes mellitus. A

deficiency of insulin prevents the animal from utilizing the glucose circulating in the blood stream. Insulin is

needed to get glucose to enter the body cells, consequently the animal breaks down fat for energy. Excessive amounts of acetyl-Coa (product A) starts to accumulate in the blood. Accumulated product A is

converted to Ketone Bodies, large amounts of ketone bodies cause a condition called ketosis. Ketosis is life threatening because ketone bodies are acidic and the body can not function when the blood drops below a

pH of 7.35.

National Exam note:

• Normal Animal = blood pH 7.4

• If pH rises above 7.45 = alkalosis

• If pH goes below 7.35 = acidosis

• Normal range pH of blood: 7.35 – 7.45