Vitamin E

Question 1

Vitamin E - Structures

Answer 1

-  A family of compounds known as tocopherols;
-  Alpha-tocopherol is the most active;
-  D-isomers are naturally occurring and more
active than the synthetic L-isomers;
-  Most commercial vitamin E preparations are…
DL-a-tocopheryl acetate

Question 2

Vitamin E - Functions

Answer 2

Antioxidant
-  Primary lipid-soluble free radical scavenger;
-  Important for maintaining cell membrane integrity by protecting unsaturated fatty acids in membranes.
-  Required for normal reproduction
-  Used to be claimed to enhance fertility and
virility…

Question 3

Vitamin E - Deficiency

Answer 3

1.   White muscle disease
2. Exudative diathesis
3. Encephalomalacia
4.   Reproductive failure

Question 4

Vitamin E - Deficiency

What is associated with white muscle disease?

Answer 4

•   Occurs in young growing animals: calves, foals, chicks;

-   Usually from poor maternal vitamin E status.

Question 5

Vitamin E - Deficiency

What is associated with Exudative diathesis

Answer 5

• Occurs in chickens;

-   A result of fragile blood capillaries which causes fluid leakage (edema)

Question 6

Vitamin E - Deficiency

What is associated with Encephalomalacia

Answer 6

•   Crazy chick disease;

-   Lack of coordination “chicks fall over but can’t get up!”

Question 7

Vitamin E - Deficiency

What is associated with Reproductive failure

Answer 7

• Embryonic degeneration;

-   Sterility from testicular atrophy

Question 8

Vitamin E – Interactions with other nutrients

Answer 8

1.   Interrelationship with PUFA…
2.   Interrelationship with Selenium (Se)…
3.   Interrelationship with vitamin A…

Question 9

Interrelationship with PUFA causes?

Answer 9

More polyunsaturated fatty acids (PUFA) in the diet, the greater the need/requirement for vitamin E.

Question 10

Interrelationship with Selenium (Se) causes?

Answer 10

-  Se is a component of an enzyme, glutathione
peroxidase, that regenerates vitamin E after it
neutralizes free radicals.
-  Some functions of vitamin E can be met by Se.

Question 11

Interrelationship with vitamin A causes?

Answer 11

• Protect vit. A from oxidative destruction

- Excessive vitamin A reduces vit. E absorption, thus more vit. E is needed.

Question 12

Vitamin E Requirements

Answer 12

• 1 mg alpha-tocopherol = 1 I.U.
  •   Dairy cattle: 300 IU/kg diet
  •   Beef cattle: 15-60 IU/kg diet
  •   Swine: 11-22 IU/kg

Question 13

Vitamin E Toxicity

Answer 13

• Health claims: Extra vitamin E may enhance immune response in various animals and people;
  (However, data are inconsistent in this area!)
  -  Although vitamin E is a fat-soluble vitamin…
  toxicity is not a problem;
  -  One of the more expensive $$$$$ vitamins