Vitamins and minerals

Why are vitamins and minerals considered essential nutrients for animals?

Iron-red blood cells

Vitmin E/Selenium: antioxidants: crucial for preventing cell damage

How are minerals classified?

Based on the abundance in tissues

What are the two classifications for minerals?

macro minerals and trace minerals

In what concentration are macro minerals and trace minerals available?

• Trace minerals are present concentrations of <100 mg/kg or 100 ppm (0.01%)

• Macro minerals are present at greater than 100 ppm (>0.01%), some thousands of times higher

Name the macro minerals

• Calcium

• Phosphorus

• Magnesium

• Sulfur

• Sodium

• Chlorine

• Potassium

Chinese People Make Super Salty Chicken padthai

Name the trace minerals

• Cobalt

• Copper

• Iodine

• Iron

• Manganese

• Selenium

• Zinc

• Molybdenum

Cool Cows In Italy Make Strong Zinc Milk”
(this one actually ties back to nutrition)

• Others that might influence health, but these are less abundant, and their role is unclear

What are minerals and where can we find them?

• Inorganic ions found in the body, ~4% of body in humans

• Varies by animal

Minerals have many functions but many have some role us _____ reactions

enzyme

Which minerals are important for acid-base and water balance

- Na, K, Cl

What minerals are important for structure in bone and in keratin

In bone: Ca, P

Keratin: S

Which minerals has a function in…

1. heme

2. Vitamin B12

3.Thyroid hormones

1. Fe

2. Co

3. I

What are some factors which influence mineral requirements?

• Physiological state and level of production

• Interactions with other minerals

• Tissue storage

• The form fed – digestibility or availability

Most minerals have a optimal range, below is considered…

deficiency

Some deficiency or toxicity symptoms can take extended periods – months – to develop especially if it can be stored

Above can lead to…

toxicity

How do minerals in soil correlate to feed?

Minerals in soil can determine the mineral content of feeds produced from them

What are vitamins?

Vitamins are organic compounds required in small amounts for normal functions

Why is it difficult to classify vitamins?

• Vitamins are chemically and biologically diverse so difficult to classify

• Not fuels like glucose/fatty acids or structural like amino acids/Ca/P

• Generally act as facilitators or catalysts for metabolism of other nutrients

How are vitamins classified?

Classified according to solubility

What factors are considered when classifying vitamins

• Relates to digestion

• Fat soluble

• Water soluble

Name the fat soluble vitamins

• Vitamin A

• Vitamin D

• Vitamin E

• Vitamin K

Name the water soluble vitamins

• B1 Thiamin

• B2 Riboflavin

• B3 Niacin or nicotinamide

• B6 pyridoxine

• Pantothenic acid

• Biotin

• Folic acid

• Choline

• B12 cyanocobalamin

• C ascorbic acid

Are all vitamins required in the diet?

• All vitamins are metabolically essential, but not all are necessarily required in the diet depending on the diet and vitamin

Most mammals synthesize Vitamin C except….

humans, primates, guinea pigs, bats, and some fish and bird species

Which mammals synthesize B vitamins?

No mammals synthesize B vitamins but rumen bacteria produce them and so they have a source other than the diet

What are provitamins?

Some compounds are vitamins only after conversion through chemical change – called provitamins

• β-carotene to vitamin A, for example

Which vitamin and mineral are known for regulation?

Vitamin D and Calcium

Support for absorption, regulation of calcium levels

Which mineral goes along with Vitamin E, and why?

Vitamin E and selenium

• Both antioxidants preventing oxidative damage in cells

What are metals for protein and enzyme functions

Iron and copper

• included as electron carriers in enzymes

How do we formulate feed for animals?

we formulate feed for animals on a dry matter basis

When moving from as fed to dry matter do nutrients increase or decrease?

increase

• remove the water, concentrate what remains

When moving from as fed to dry matter do amounts (weights, masses) increase or decrease?

decrease

• remove the water, less weight

when moving from dry matter to as fed nutrients and concentrations increase or decrease?

decrease

• remove the water, less weight

when moving from dry matter to as fed do amounts (weights, masses) increase or decrease?

increase

• add the water, more weight

If a feed is 44% crude protein on a dry matter basis and 90% dry matter, what is the crude protein concentration on an as fed basis?

If a feed has 1.1 Mcal/kg on as fed basis and 36% dry matter, what is the energy concentration on a dry matter basis?

Where is most Ca and P found?

In the skeleton

What percent of Ca and P are found in the skeleton?

99% of Ca is skeletal

80% of P is skeletal

How are Ca and P primarily found in the bone?

As hydroxyapatite

Ca10(PO4)6(OH)2

How is Ca and P found in the blood?

• Some is free and ionized in circulation

• Some associated/bound to proteins or lipids (phospholipids)

What tissues are Ca and P found in?

• Ca in muscle and nerve cells

• P in molecules like DNA and RNA, lipids – found in virtually all cells

What is the ideal dietary ratio for Ca and P?

1:1 ro 2:1

What animal is the exception for the typical Ca:P dietary ratio?

Layers

• laying hens need a higher ratio of Ca

What does a deficiency of Ca, P, or Vitamin D cause in young animals?

Rickets: misshapen bones, lameness

What does a deficiency of Ca, P, or Vitamin D cause in old animals?

Osteomalacin: brittle bones

What does a deficiency of Ca, P, or Vitamin D cause in cows?

Milk “fever” - periparturient paresis - inability to stand at parturition

• insufficient calcium for the body due to sudden demand to support milk production

Ca is controlled to maintain what?

a relatively consistent level in plasma

Bone is dynamic meaning?

continuous turnover and remodeling

how is plasma (extracellular fluid) Ca and P regulated?

By hormones

Dietary factors that affect circulating Ca affect hormones controlling…

bone metabolism and Ca absorption

Why is P metabolism related to calcium?

because of tie to bone

• if Ca is incorporated into bone, P is incorporated

• if Ca is reabsorbed from the bone, P is reabsorbed

What is calcitonin?

Calcitonin is a hormone made and released to help regulate calcium levels in your blood by decreasing them.

When is calcitonin released?

when plasma Ca increases

Where is calcitonin produced?

Produced by the thyroid gland

• C cells

What are the 2 ways in which calcitonin reduces plasma calcium

• decreases reabsorption of Ca in Kidneys

• Inhibits bone osteoclasts

  • reduces breakdown of bown and release of Ca

When is parathyroid hormone released?

When plasma Ca concentrations are low

what produces parathyroid hormone?

the parathyroid gland

What does parathyroid hormone do?

increases plasma Ca

• stimulates production of vitamin D

• Increases Ca absorption from intestine

What does parathyroid hormone do to osteoclasts?

stimulates osteoclasts to reabsorb bone Ca

what does parathyroid hormone do to the kidney?

Promotes Ca, reabsorption in kidneys

• reduced urinary loss

What are the two forms of vitamin D?

D₂ and D₃

What is the plant source of Vitamin D?

Ergosterol is the plant source

What is the source of Vitamin D in animal tissues?

7-dehydrocholesterol

What triggers the conversion of ergosterol and 7-dehydrocholesterol to Vitamin D?

UV light

After exposure to UV light ergosterol is converted to?

Vitamin D₂ (ergocalciferol)

After exposure to UV light 7-dehydrocholesterol is converted to?

Vitamin D₃ (Cholecalciferol)

What is the essential first step of Vitamin D activation?

hydroxylation in the liver

What is the main circulating form of vitamin D?

25-hydroxyvitamin D₃ (25-hydroxyD₃)

Does 25-hydroxyvitamin D₃ have direct biological activity?

No, it has no direct action

What is the second step in vitamin D activation?

Hydroxylation in the kidney

What are the active forms of vitamin D produced in the kidney?

1,25-dihydroxyvitamin D₃ and 24,25-dihydroxyvitamin D₃

How is active vitamin D transported in the body?

Carried through the blood to target tissues

How does active vitamin D function in the body?

Acts as an endocrine hormone

What does active vitamin D do at target tissues?

Acts directly on target tissues

One of Vitamin D’s functions is to raise ___ and ___ levels to support normal ___ mineralization

Ca

P

bone

What does active vitamin D do in the intestines?

Stimulates transport of calcium and phosphate across the intestinal epithelium

How does active vitamin D affect the kidneys?

Stimulates reabsorption of calcium and phosphate

What effect does active vitamin D have on bone?

Stimulates osteoclasts to release calcium and phosphate

What is the overall effect of active vitamin D on calcium and phosphate levels?

Increases calcium and phosphate levels in the blood

What is calcitriol?

The active form of vitamin D (1,25-dihydroxyvitamin D₃)

How does calcitriol function in the body?

Acts as an endocrine hormone that regulates calcium and phosphate balance

What is an enterocyte?

An absorptive epithelial cell lining the small intestine

What is the primary function of enterocytes?

Absorption of nutrients, including calcium, from the intestine

What is calcitriol’s role in enterocytes?

Regulates and increases calcium absorption in the intestine

What are the three components involved in enterocyte calcium absorption?

An apical membrane transporter, an intracellular calcium-binding protein, and a basolateral transporter

Where does wasting disease originate?

Ruminants grazing where there was Co deficiency in plants and soils had wasting disease

Co deficiency is highly localized in..

parts of Midwest and east especially Florida and coastal Carolinas

What relieved the wasting disease?

feeding cobalt

Which vitamin was found to contain cobalt?

B₁₂

What other than feeding cobalt relieved the wasting disease?

Injecting B₁₂

Injecting Co did not relieve the wasting disease

What was happening? what explains the findings?

Ruminants developed a vitamin B12 deficiency because cobalt-deficient soils prevented rumen microbes from synthesizing B12; feeding cobalt restored microbial production, injecting B12 bypassed the need for synthesis, and injected cobalt failed because it did not reach the rumen microbes.

Vitamin B₁₂ is _____ (meaning it contains cobalt)

cobalamin

This synthesis is the reason why ruminants can be fed Co and receive adequate B₁₂

Microbial synthesis of bacteria

How do non-ruminants obtain vitamin B12?

From dietary sources, primarily animal products

Why was vitamin B12 originally called “animal protein factor”?

Animals fed diets without animal protein developed blood and neurological disorders

How can vitamin B12 deficiency be prevented in animals without animal protein in their diet?

By supplementation with vitamin B12

What is another way some animals obtain vitamin B12 besides diet?

Coprophagy (consumption of feces)

Vitamin B₁₂ is need for the the production of ________

deoxyribonucleotides - needed for DNA synthesis

What metabolic process in ruminants requires vitamin B12?

Propionate metabolism

What is propionate?

A short-chain (volatile) fatty acid produced during carbohydrate fermentation in the rumen

Why is propionate important in ruminants?

It is the major substrate for gluconeogenesis