Lecture 17- Vitimans Flashcards
Who isolated an anti-beriberi substance from rice polishings?
Polish biochemist Casimir Funk
What did Russian scientsists discover in 1880?
Rodents die if they are fed “purified foods” if they added 1ml of milk to the diet the mice remained healthy.
What where synthesized by the microflora within the large intestine? What is the exception?
-Several of the B vitamins and the K vitamins
-Ruminants
Whats a folklore medicine …
Cod liver oil
List 4 general functions of vitimans:
1-Nuture growth: reproduction : maintain life.
2-Prevent deficiency diseases
3-help enzymes release energy from carbohydrates, lipids and proteins
4-They are regulator molecules. they regulate normal growth and development
Do vitimans provide energy by themselves?
NOOOO
Name the 2 classification groups of vitamins:
1-Chemically and biologically diverse; therefore hard to classify (water soluble and fat soluble)
2-Not metabolic fuels (like glucose and fatty acids) of metabolism and other nutrients
List fat soluble vitamins that are important in animal nutrition: (5)
1- A , retinol
2- D2, ergocalciferol
3- D3, cholecalciferol
4- E, tocopherol
5-K, phylloquinone
List water soluble vitamins that are important in animal nutrition: (4)
1- B1, thiamine
2- B2, riboflavin
3- B6, pyridoxine, pantothenic acid, biotin, folacin, choline.
4- B12, cyanocobalamin
Are all vitamins essential?
All vitamins are metabolically essential but not all vitamins
are necessarily required in the diet, depending on the diet
and the vitamin concerned.
Where is vit K made?
By the large intestine microflora
What can most mammals synthesise?
Vitamin C from glucose
What can ruminants obtain adequate supply of?
Vitamin B from bacterial synthesise in the rumen.
1-What are fat soluble vitamins absorbed with?
2-What % is the absorption efficiency?
3-What is the absorption typically regulated by?
4-What happens after this whole process occurs?
1-Dietary fat across small intestine. (hydrophobic)
2-40-90% absorption efficiency.
3-Increased need=increased absorption rate.
4-Transported away from the small intestine in chylomicron via the lymph
What does the liver do with fat soluble vitamins?
Liver either stores the vitamin or repackages it for delivery to other cells
Where do access fat soluble vitamins accumulate ?
They accumulate in the liver and adipose tissue
What is always (nearly always) associated with fat soluble vitamins? how are these toxicities excreted?
Toxicities almost always occur
Can be excreted by the liver through bile.
Do you need to consume bile on a regular basis?
No you do not need to consume fat soluble vitamins on a regular basis
List the Water soluble, B complex vitamins: (7)
1- B1
2- B2
3- B3
4- B5
5- B6
6- B12
7- C
Where are water soluble vitamins absorbed?
Small intestine
-What is water soluble vitamins absorption often?
-Where are they transported to?
-Where are they stored?
-What’s the bottom line with these vitamins?
-Highly regulated by wither other vitamins or binding proteins in the small intestine.
-Transported away from small intestine in blood
-Typically not stored instead kidney filters excess into urine.
-More important to provide these vitamins daily. (Toxicities are rare)
What are the categories of water soluble vitamins?
-Vitamin C
-B complex vitamins
What is fat soluble vitamins closely associated with?
What does this require?
What is this transported by?
Where is this stored?
Absorption and transport of lipids (requires bile salts) (transport by chylomicrons)
-Stored in body lipids.
Where are water soluble vitamins absorbed?
Are they kept in the body for a long period of time?
How/When are they excreted?
-Directly into the portal blood
-Not retained by body for long periods of time (exception is B12)
-Excreted in urine when plasma levels exceed normal.
What type of vitamins are absorbed in the small intestine?
-Water soluble and Fat soluble.
What type of vitamins are hydrophilic?
Water soluble vitamins
What type of vitamins are hydrophobic?
Fat soluble
What vitamins are absorbed into the blood?
Water Soluble
What type of vitamins are absorbed into the lymph?
Fat-Soluble
What vitamins are generally not stored in the body?
Water-Soluable
What type of vitimans are stored in the body?
Fat soluble
What vitimans generally dont build up and become toxic?
Water soluble
What vitamins can become toxic if they build up?
Fat soluble
What vitamins do we need to consume daily?
Water soluble
What vitamins do we not need to consume daily?
Fat soluble
Are vitamins found in all types of feed?
Yes
What can decrease the amount of vitamins in feed?
Food processing
Vitamins from animals are generally more what?
More bioavailable/digestible than those in plants.
What makes vitamins destructive? (looses stability)
-Oxygen, heat, acids, trace minerals.
Why should you use feed within 3-4 weeks after mixing?
Or why would you increase dietary vitamin levels to account for losses?
Vitamins loose there activity overtime(stability is effected)
What’s the Units to measure fat soluble vitamins?
IU - A measure of biological activity
What does ICU stand for?
International check unit (used to express vitamin D requirements of poultry )
What are other vitamin measured in weight units as?
ug, ng, mg
What are provitamins?
Provitamins function as
vitamins only after
undergoing a chemical
change in the body.
e.g. β‐carotene to vitamin A
-Where can you get Vit A from?
-Animal sources. They provide various retinoids that are easily converted to retinol in the body. , plant sources don’t contain vitamin A but they provide carotenoids. (precursor of Vit A)
Whats the provitamin A?
β-carotene
How many carotenoids are found in nature?
500
– Less than 10% with provitamin A activity
– B-carotene highest activity
– Must be acted upon in the gut or by the liver to form retinol
What does Vitamin A give to plants?
The red, orange, yellow pigment.
What are carotenoid used in the food industry for?
As a colorant (orange)
Where is Vitiman A:
-Stored
-Used as
-Important for
In liver
Used as an antioxidant
Important for sight
What does deficiency of Vitamin A cause?
Night blindness (500,000 causes worldwide)
What can prevent blindness at night?
Rice with high vitamin A can prevent night blindness
What did the ancient Greeks do to get vit A?
night blindness cured with eating liver or application of liver juice to the eyes
What are sources of Vit A?
Animal sources:
-Liver (the [Vit A] content of polar bear liver is so
high that it can be toxic to humans)
-Milk
Egg yolk
Fish (tuna, sardines, herring)
Plant sources: (Provitamin)
-Alfalfa
-Green leafy vegetables
-The chlorophyll masks the red/orange colour
Whats Vit D also known as?
Whats Vit D main role?
Calciferol due to its role in calcium absorption.
Its main role is to regulate and maintain calcium and potassium levels.
What type of vitamins can animals synthesise in the presence of sunlight?
Fat soluble vitamins
What can vitamin D be made from?
Cholesterol
What does vit D act more like?
a hormone than a vitamin
What are sources of Vit D?
-Primarily in foods if animal origin (Liver, dairy, eggs, oily fish)
-Not found naturally in many foods.
-Plants
-Fluid milk product’s are fortified with vit D
Whats another name for Vit D?
Calciferol
Whats another name for Vit D2?
Ergocalciferol
Whats another name for Vit D3?
Cholecalciferol
What is Vit D3 produced by?
Photochemically by the action of sunlight or ultraviolet light from the precursor sterol 7-dehydrocholesterol
What can rickets be caused by?
Lack of sunlight , but also from insufficient calcium and phosphors
When was there an era of rickets in Europe?
Industrial revolution. Because people moved from farms and into cities, working indoors.
Name the 2 functions of Vit D:
1- Bone development
2-Hormone
Whats vit D also known as and why, what is it ,made from?
The sunshine vitamin.
Not always essential body can make it if exposed to enough sunlight. Made from cholesterol.
How is Vit D formed?
in
1-Skin(UV light)
2-Liver
3-Kidney
1- *7-dehydro cholesterol (turned into) vit D3
*Ergosterol (turned into) vit D2
2- *OG group added
3- *OH group added by 1- hydroxylase
Name the active form of Vit D 3?
1,25- Dihydroxy vitamin
What does a vit D deficiency cause ?
Rickets (in young animals)
Ostermalacia or osteoporosis (in older animals)
Poultry (decreased egg production & hatchability. Thin shelled eggs.
What can Vit D toxicity cause?
Anorexia, nausea, hypertension(high blood pressure).
Hyper-calcification of soft tissue. (hardening of arteries)
Hypercalcemia (normal is 10mg/dl)
Excess blood calcium leads to stone formation in kidneys.
What is another word for Vit E?
Tocopherol
What is Vit E essential for?
Factor for rodent reproduction.
What type of fam is Vit E?
Fam of 8 naturally occurring compounds (syntheses by plants)(tocopherols and tocotrienols)
What is Vit E used as ?
An antioxidant in foods
Whats strange about the deficiency’s of Vit E?
They arent well understood.
Americans spend $300 million per year on vit E supplements.
List sources of Vit E:
Plant sources:
Cereal grains (Especially germ)
Veg and seed oils
Animal sources:
Not nearly as good of a source as plants.
Concentrated in fatty tissues.
Beef fed high levels of vit E right before slaughter to improve shelf like can be source
What does Vit K contribute to?
How can it be reactivated ?What does it work as?
-Synthesis of 7 blood clotting factors.
-Reactivated to continue biological action.
-Works as a cofactor for an enzyme that makes two bone proteins.
List sources of Vit K
1-Bacteria in the large intestine (10-15%) or rumen
2-Plant sources: Green leafy veg, some oils, broccoli.
3-Animal Sources: Milk, liver.
Whats the functions of Vit K?
Clotting factors are synthesised in the liver as inactive precursors. Vit K converts them to their active forms.
Name 2 antagonists of Vit K:
1- Dicoumarol and Warfarin (they both prevent coagulation)
Where is Dicoumaloral found?
In mouldy sweet clover
What is the story with sweet clover disease?
- Especially after procedures that causes bleeding
- Cattle were dying from dehorning and castration
What medication was used to thin blood?
Waefarin
What are 2 Vit K deficiency in humans resulting in?
1) Hemorrhagic disease in first few days of life;
death caused by subdural hemorrhage
(Vit K given at birth)
2) Antibiotics
1) Reduces bacterial synthesis and thus absorption
Name the 2 water soluble vitamin’s :
B vitamins and C vitamins
What originally where B vitamins thought to be?
What do they act primarily as?
They thought there was just 1 Vitamin.
But there where actually 8. They act primarily as coenzymes in metabolic pathways (important for ATP production)(Important for MANY additional functions.)
Where is Vit B present?
Present in plant and animals cells. Widley distributed in feeds.
What does Vit B generally act as?
Components of coenzymes in energy - yielding reactions.
What is the vit B dietary requirement closely liked with?
Closely linked to metabolic rate
What are Vit B ruminant requirements met entirely by ?
Ruminant requirements are met entirely by rumen bacterial synthesis (they don’t need to consume, they make there own)
What is the story with Vit B tissue storage?
Must be continually supplied in diet or by ruminal synthesis
Whats the story with Vit B functions?
Several B vitamins have close general functions but each has a specific role
What are ruminant requirements if B vit met by?
Rumen bacterial synthesis (The microbes synthesise B vitamins)
Does hindgut bacterial synthesis and absorption meet full requirements for a horse?
No its insufficient
Coprophagy helps to recycle and better utilise vitamins for cecal fermenters
What are Vit B sources :
Plant sources:
-Fibrous portion of plant
-Most cereals and grain products and enriched
Animal sources:
-Liver
-Milk
-Egg
-Beef, pork, chicken
What a symptom of a vit B deficiency :
Fatigue (but theres lots of sympotms)
Whats Vit C also known as?
Whats it found in?
Whats is destroyed by?
Ascorbic acid, ascorbate.
Found in Citrus fruits etc.
Destroyed by exposure to oxygen and destroyed by heat.
What do most mammals synthesize ascorbate from? Who needs a dietary source of Vit C?
Glucose including farm animals
(Primates and guinea pigs require a dietary source of Vit C)
Who lacks the terminal enzyme , gluconolactone oxidase in the ascorbate biosynthetic pathway?
Humans and other primates.(we cant make our own vit C so we have to have it in our diet
What does Vit C (Ascorbic Acid) act as?(5)
1-Antioxidant
2-Assists as co-factor in collagen formation
3-Helos in the hydroxylation of carnitine
4-Conversion of tryptophan to neurotransmitters serotonin and norepinephrine.
5-Enhances iron absorption and regulates the absorption of copper.
What is caused by a deficiency of Vit C
?
Scurvy in humans.
– Not observed in farm animals
– Structural defects of bone, connective tissue
– Bleeding gums; pinpoint hemorrhage
– Fatigue; microcytic anemia
– Loss of appetite
– Slow wound healing; frequent infections
– Scaly and dry skin; neurological symptoms
– Edema
– Loose teeth, gum problems
– Diarrhea
Who found citrus fruits that prevented scurvy by experimenting on British sailors?
1930’s- James Lind
