Vitamins D,E,K

What vitamins are fat soluble?

A, D, E, and K

Why is vitamin D important?

• necessary to use Ca and P

• deficiency causes RICKETS (in young animals—>bones become soft and weak)

• deficiency in old animals causes osteomalacia—>also softening of bones

• can be gotten from sunlight on skin

• active form is 1,25 dihydroxycholecalciferol

• form in plants = D2

• form in animals = D3

What vitamin D form is in plants? animals?

plants = D2

animals = D3

Describe how vitamin D is a hormone (how it becomes active form of 1,25 dihydroxycholecalciferol)

• vitamin D activated by UV light from 7-dehydro-cholesterol in skin and goes to liver

• in liver, is hydroxylated in 1 position

• in kidney, is hydroxylated in 25 position

• 1,25 dihydroxycholecalciferol = active form

How does vitamin D metabolize?

• facilitates deposition of calcium and phosphorous in bone

• increases the absorption of Ca and P from intestine

What are the vitamin D deficiency symptoms?

• young animals

  • rickets with weak, easily broken bones, bowed legs

• young cattle

  • swollen knees and hocks and arching of back

• pigs

  • enlarged joints, broken bones, stiffness of joints, occasional paralysis

• older animals

  • osteomalacia

• poultry

  • soft, rubbery bones and beak, retarded growth, bowed legs, reduced egg production

What are problems with vitamin D?

• need is greater for pigs and poultry than cattle and sheep

• animal housed indoors may need supplemented

• more vitamin D may be helpful managing milk fever (low calcium in blood—>boost absorption)

What can you get sources of vitamin D?

• most feeds for pigs/poultry = poor sources

• cod and fish-liver oils = good sources

  • also sun-cured hays

  • also irradiated yeast of D2

What does excessive amounts of vitamin D do?

• high doses mobilize Ca and P from tissues causing vitamin D rickets

• may cause deposition of calcium salts in arteries, various organs, and tissues (places where it shouldn’t belong)

What is vitamin E?

• major anti-oxidant

• protects membranes

• interacts with selenium

• prevents muscle, liver, blood vessel degeneration

What are the deficiency symptoms of vitamin E?

• liver cells die

• stiff lamb disease

• white muscle disease (calves)

• exudative diathesis (chickens)

  • membranes leaky

• reproductive failure

• calves and lambs = muscular degeneration

• chicks = nutritional encephalomalacia (softening of brain)

• pigs = sever liver damage, muscular weakness, heart muscle affected with sudden death

What are the functions of vitamin E?

• biological anti-oxidant

• normal tissue respiration

• normal phosphorylation rxns

• metabolism of nucleic acids

• synthesis of absorbic acid

What is the relationship between vitamin E and selenium?

• interrelationship not known

• can be prevented by administering selenium/vitamin E (muscular dystrophies in sheep and cattle)

• necrotic liver degeneration in rat and exudative diathesis in chick prevented by either substance

• nutritional encephalomalacia in chick/ muscular dystrophy by vitamin E injection, not selenium

What are good sources for vitamin E?

• good

  • wheat germ (part of seed plant—>oil)

  • green forages

  • soybean, peanut, cottonseed oils

• poor

  • corn

    • soybean, peanut, cottonseed meals (oils removed)

What is vitamin K?

• necessary for blood clotting

• normally enough by microbial synthesis

  • menadione synthetic (vitamin K3 source) NO LONGER USED

• naturally naphthoquinone = K2

• menadione = K3

What are the functions of vitamin K?

• necessary for formation of prothrombin

  • blood clotting

• also for…

  • bone formation

  • circulatory system

What are the deficiency symptoms of vitamin K?

• prolonged clotting time

• hemorrhage

Problems with vitamin K?

• synthesis by microbes even in non-ruminants (if antibiotic used = no vitamin K)

• add to non-ruminant diets anyway

• beware moldy sweet corn clover poisoning