Fat soluble vitamins

Question 1

Which molecules are very water soluble?

Answer 1

• COOH

- C-Cl

Question 2

Which molecules are moderately water soluble?

Answer 2

-COH

Question 3

Which molecules are not water soluble (fat soluble)?

Answer 3

-CH2-CH2-CH3

Question 4

What are the fat soluble vitamins?

Answer 4

K, A, D, E

Question 5

What are the water soluble vitamins?

Answer 5

all the others - especially B group & C

Question 6

Which vitamins can herbivores not produce?

Answer 6

A & E (fat soluble)

Question 7

Which vitamins can most animals produce?

Answer 7

C & D (vit D needs sunlight)

Question 8

Which vitamins can microbes produce?

Answer 8

B group & K

Question 9

In which conditions may vitamin supplements be needed?

Answer 9

1. When on antibiotics
2. high grain diets or drought (Vit A & E)
3. poor quality diets
4. animals in poor sunlight (vit D)
5. stress or infection
6. nervous or hyperactive
7. reduced appetite
8. anaemia

Question 10

How should vitamins be stored?

Answer 10

cool & dry to maintain potency

Question 11

Vitamin A (retinol) functions/roles…?

Answer 11

• Required for vision -> initiates impulse transmission along optic nerve
• formation & protection of epithelial tissue & mucous membrane
• free radical scavenger (antioxidant)

Question 12

Deficiency symptoms of vitamin A…? Include sub-clinical deficiency symptoms

Answer 12

Excess lacrimation (tearing)
night blindness (lack of rhodopsin synthesis in dark reaction)
sub-clinical - rough hair coat, reduced immune response, infertility

Question 13

Sources of vitamin A…?

Answer 13

green leaves (4-6 weeks grazing green forage provide enough stores (liver) for 3-6 months)
corn
grains (poor)
decreases in cutting & storage

Question 14

Excess/toxicity of vitamin A…?

Answer 14

fragile bones

dull hair

Question 15

Vitamin D functions/roles…?

Answer 15

calcium metabolism (uptake from gut & deposition in bone)
can be synthesised in skin (UV)

Question 16

Deficiency symptoms of vitamin D…? Which animals most likely affected?

Answer 16

pet reptiles (animals housed indoors/behind glass as UV does not pass thru glass or plastic)
metabolic bone disease (MBD) -> Ca-deficiency -> scoliosis

Question 17

Vitamin K functions/roles…?

Answer 17

required for synthesis of prothrombin - BLOOD CLOTTING (inactive precursor of thrombin - converts fibrinogen -> fibrin)

Question 18

Deficiency of vitamin K…?

Answer 18

-> decrease prothrombin & carboxyglutamic acid (needed for Ca binding)
deficiency occurs a few weeks after vit. K not available
causes internal haemorrhage, bruising, poor blood clotting, malformation of dev. bones

Question 19

What else can cause vitamin K symptoms?

Answer 19

accidental ingestion of rodenticides, anticoagulants, coccidiostats (antiprotozoal agents) which contain vit. K antag’s.
‘sweet clover disease’

Question 20

Sources of vitamin K…?

Answer 20

Green, leafy material - good source

microbes -> synthesise enough to meet requirements in ruminants

Question 21

Some conditions in birds deficient in vitamin K?

Answer 21

spontaneous subcutaneous haemorrhage

perifollicular petechiae of the skin (due to frail capillary walls)

Question 22

Vitamin E storage & functions (many)…?

Answer 22

Stored in liver (dietary fat is needed for absorption of vit E from GIT)
(8 different isoforms)
ANTIOXIDANT (ESP FOR FAT METABOLISM)
IMMUNE FUNCTION
aids in RBC formation & use of vit K
replete endothelial cells of blood vessels -> resist platelets adhesion (prevent ‘false-alarm’ clotting in capillaries)
cell signalling (regulate gene expression)
neuro function

Question 23

How do vitamins E and C work together as antioxidants?

Answer 23

Fat metabolism (oxidation) in cell membrane -> free radical + active electron. Vit. E ‘mops’ up the electron. Vit. C comes along, accepts the electron and passes it onto electron carrier (NADH) while vit. C returns to its active form

Question 24

What are the 3 likely situations for Vitamin E deficiency…?

Answer 24

usually caused by poor uptake rather than inadequate diet

1. premature, very low birth weight animals
2. animals which cannot absorb dietary fat
3. animals with rare genetic disorders of fat metabolism

Question 25

What are the symptoms of vitamin E deficiency…?

Answer 25

• reduced immune response
• neuromuscular probs - spinocerebellar ataxia (intention tremor)
• anaemia due to oxidative damage to RBC’s

Question 26

What are the implications of high doses of vitamin E?

Answer 26

can be fatal as it is FAT soluble so more difficult to excrete excess

Question 27

Good natural sources of vitamin E…?

Answer 27

Wheat grain

most seed oils (wheatgerm, sunflower, safflower, canola oils

Question 28

When would one supplement vitamin E?

Answer 28

in premature, very low birth weight animals

animals on low-fat diets