Omega Fatty Acids

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Omega Fatty Acids
2
Essential Fatty Acids

• Used as an energy source
• Used in the production of hormones
• Are incorporated in cell membranes

3
DeNovo Fatty Acid Biosynthesis

• Birds can synthesize saturated fatty acids de
  novo and oxidize them to mono- and diunsaturated
  fatty acids up to C-9 in from the carboxyl end (
  delta 9).

4
DeNovo Fatty Acid Biosynthesis

• Birds can synthesize saturated fatty acids de
  novo and oxidize them to mono- and diunsaturated
  fatty acids up to C-9 in from the carboxyl end (
  delta 9).
• For example, avian liver cells can synthesize
  stearic acid (C 18) and introduce a double bond
  between C-9 and C-10 to give oleic acid
• ( C 18 1 9 ).

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DeNovo Fatty Acid Biosynthesis

• Acetate ? 160 ? 180
• palmitic stearic
  
• Malonate
• ?------------------------?
  
• elongation
  
• 
  

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DeNovo Fatty Acid Biosynthesis

• Acetate ?160 ? 180 ? 9 desaturase? 181
  
• palmitic stearic
  oleic
• Malonate
• 
  
• ?------------------------?
• elongation
  
• 
  

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• Birds cannot introduce double bonds past the 9
  so they cannot use stearic acid to synthesize
  linoleic acid (C 182 9, 12) or
• a linolenic acid (C 183 9, 12, 15 ).

8

• Birds cannot introduce double bonds past the 9
  so they cannot use stearic acid to synthesize
  linoleic acid (C 182 9, 12) or
• a linolenic acid (C 183 9, 12, 15 ).
• Only plants have the enzymes capable of
  inserting 12 or 15 double bonds into C 18
  fatty acids, hence linoleic and linolenic acids
  are essential fatty acids for birds.

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DeNovo Fatty Acid Biosynthesis

• Acetate ? 160 ? 180 ? 181? 182?
  183
• palmitic stearic
  oleic linoleic linolenic
• Malonate
• 
  9 12 15
• ?------------------------?
  ?---------------------------?
• elongation
  desaturation
• 
  plants

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• It is common to name fatty acids by referring to
  the position of double bonds relative to the
  methyl end of the molecule.

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• It is common to name fatty acids by referring to
  the position of double bonds relative to the
  methyl end of the molecule.
• This is appropriate because the methyl end is not
  subject to elongation and desaturation and
  determines nutritional essentiality.

12

• It is common to name fatty acids by referring to
  the position of double bonds relative to the
  methyl end of the molecule.
• This is appropriate because the methyl end is not
  subject to elongation and desaturation and
  determines nutritional essentiality.
• Linoleic acid and its elongation products are
  referred to as the n-6 or omega 6 family of fatty
  acids.

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Linoleic Acid (182)
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Nomenclature

• The n designation indicates the number of
  carbons from the methyl end.

15
Nomenclature

• The n designation indicates the number of
  carbons from the methyl end.
• The (delta) designation indicates the number of
  carbons from the carboxyl end.

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Nomenclature

• The n designation indicates the number of
  carbons from the methyl end.
• The (delta) designation indicates the number of
  carbons from the carboxyl end.
• Birds can introduce double bonds at the
• 5, 6, and 9 positions.

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Linoleic Acid (182)
18

• Once consumed, linoleic can be desaturated
  between C-6 and C-7 to yield gamma-linolenic (C
  183 6, 9, 12) which can be further elongated
  ( 2 C) and desaturated to give arachidonic acid
  (C 20 4 5, 8, 12, 14 ).

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• Once consumed, linoleic can be desaturated
  between C-6 and C-7 to yield gamma-linolenic (C
  183 6, 9, 12) which can be further elongated
  ( 2 C) and desaturated to give arachidonic acid
  
• (C 20 4 5, 8, 11, 14 ).
• Arachidonic can be further metabolized to
• C 22 fatty acids such as prostaglandins.

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• C 182 9, 12, n-6 (linoleic acid) ?6
  desaturase ?
• C 183 6, 9, 12, n-6 (gamma-linolenic) 2 C ?
  
• C 203 8, 11, 14, n-6 ? 5 desaturase ?
• C 204 5, 8, 11, 14, n-6 (arachidonic acid)

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Sources of Omega 6

• Sunflower oil
• Corn oil
• Poultry fat
• Pork fat

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a-Linolenic Acid 183
23

• Dietary a-linolenic acid can be elongated and
  desaturated by hepatocytes to give
• eicosapentanoic acid ( C 20 5 5, 8, 11, 14,
  17) which can be further elaborated to other C 22
  fatty acids.

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• C 183 9, 12, 15, n-3 (a-linolenic acid) ?
• 6 desaturase ? 184 6, 9, 12, 15, n-3 2 C
• C 204 8, 11, 14, 17, n-3 ? 5 desaturase ?
• C 205 5, 8, 11, 14, 17, n-3 (eicosapentanoic
  acid)?
• C 226, n-3 (docosahexanoic acid)

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Sources of Omega 3

• Fish oils from cold-water fish
• Can be unpalatable and contain contaminates
• Flaxseed
• Must be processed with added pyridoxine
• Salvia Hispanica
• Very palatable, contains antioxidants

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• The C-18, C-20, and C-22 PUFA are stored in
  phospholipids of cell membranes where they
  contribute to membrane structural integrity and
  fluidity.

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• The C-18, C-20, and C-22 PUFA are stored in
  phospholipids of cell membranes where they
  contribute to membrane structural integrity and
  fluidity.
• They are released by the action of phospholipases
  and become the precursors for the eicosanoids
  prostaglandins, leukotrienes, and thrombaxanes.

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• The ratio of n-3 to n-6 fatty acids in the diet
  is an important modulator of many physiologic
  processes and often more relevant than their
  absolute concentrations.

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• The ratio of n-3 to n-6 fatty acids in the diet
  is an important modulator of many physiologic
  processes and often more relevant than their
  absolute concentrations.
• The ratio of n-3 to n-6 is reflected in the
  composition of membranes and consequently the
  type and rate of different eicosanoids produced
  for regulatory purposes.

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Avian Immune Response

• High ratios of n-6 to n-3 are proinflammatory,
  low ratios are anti-inflammatory.
• Young chickens, n-3 fatty acids from fish oil
  enhances the immune response to sheep red blood
  cells.

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Omega-6 Fatty Acids

• The precursor product relationship means that
  the dietary requirement for linoleic acid is
  decreased with the consumption of other
• n-6 PUFA such as gamma-linolenic or arachidonic
  acids.

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Omega-3 Fatty Acids

• a- linolenic acid and its elongation products are
  members of the omega-3 family of fatty acids.
• The fat from marine animals is high in C20 and C
  22 PUFA of the omega-3 family and this diminishes
  the need for a-linolenic acid.
• Dietary n-3 PUFA do not decrease the requirement
  for n-6 PUFA because these families are not
  interchangeable.

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Deficiencies of Omega 6 3

• Dull, greasy coat
• Skin inflammation
• Dry flaky skin
• Amplified allergic responses

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Pet Food Industry

• The pet food Industry has realized the benefits
  of balancing Omega 6s 3s in pet diets
• Many companies now advertise on their labels
• High end quality diets can be purchased with an
  increase in cost

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Purina One Dog Food Label
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Carotenoid Pigments

• Birds are the most colorful of all vertebrates.

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Carotenoid Pigments

• Birds are the most colorful of all vertebrates.
• The unique colors of feathers, eyes, beaks, and
  egg yolks are often dependent upon pigments of
  dietary origin.

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Carotenoid Pigments

• Birds are the most colorful of all vertebrates.
• The unique colors of feathers, eyes, beaks, and
  egg yolks are often dependent upon pigments of
  dietary origin.
• Dietary pigments are chemically called polyenes,
  as a class are called carotenoids.

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Carotenoid Pigments

• Birds are the most colorful of all vertebrates.
• The unique colors of feathers, eyes, beaks, and
  egg yolks are often dependent upon pigments of
  dietary origin.
• Dietary pigments are chemically called polyenes,
  as a class are called carotenoids.
• Each carotenoid has a specific color ranging from
  brilliant reds, oranges, and yellows to violet.

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Carotenoids, contd

• Carotenoids are synthesized only by plants and
  are conspicuous in blossoms, seeds, fruits,
  leaves.

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Carotenoids, contd

• Carotenoids are synthesized only by plants and
  are conspicuous in blossoms, seeds, fruits,
  leaves.
• Many animals (insects, fish) concentrate and
  further metabolize cartenoids providing a rich
  source for birds.

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Carotenoids, contd

• Carotenoids are synthesized only by plants and
  are conspicuous in blossoms, seeds, fruits,
  leaves.
• Many animals (insects, fish) concentrate and
  further metabolize cartenoids providing a rich
  source for birds.
• Other animals (lab rats, mice) selectively
  excrete carotenoids.

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Carotenoids

• Carotenes unmodified cyclohexenyl rings
• a carotene
• b carotene precursor for Vitamin A in all
  species, pigment in some

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Carotenoids

• Xanthophylls oxycarotenoids, have alcohol,
  keto, or ester groups on their terminal
  cyclohexenyl rings.

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Carotenoids

• Xanthophylls oxycarotenoids, have alcohol,
  keto, or ester groups on their terminal
  cyclohexenyl rings.
• The positioning and types of groups determine the
  color of xanthophylls

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Carotenoids

• Xanthophylls oxycarotenoids, have alcohol,
  keto, or ester groups on their terminal
  cyclohexenyl rings.
• The positioning and types of groups determine the
  color of xanthophylls
• Complexing of xanthophylls with proteins may
  shift the color or give iridescence

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Carotenoids

• Dietary carotenoids may be used directly to to
  pigment tissues or they may be metabolized to
  other carotenoids prior to incorporation into
  tissues.

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Carotenoids

• Dietary carotenoids may be used directly to to
  pigment tissues or they may be metabolized to
  other carotenoids prior to incorporation into
  tissues.

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Carotenoids

• Dietary carotenoids may be used directly to to
  pigment tissues or they may be metabolized to
  other carotenoids prior to incorporation into
  tissues.
• Lutein, zeaxanthin, astaxanthin, capsanthin are
  prevalent xanthophylls consumed by captive and
  free-living birds.

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Carotenoids

• Dietary carotenoids may be used directly to to
  pigment tissues or they may be metabolized to
  other carotenoids prior to incorporation into
  tissues.
• Lutein, zeaxanthin, astaxanthin, capsanthin are
  prevalent xanthophylls consumed by captive and
  free-living birds.
• Canthaxanthin, red pigment found in flamingo
  feathers, not produced in plants

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Carotenoids

• Carotenoids are found in the diet in the free
  form or esterified to fatty acids.

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Carotenoids

• Carotenoids are found in the diet in the free
  form or esterified to fatty acids.
• Most carotenoids in fruits and seeds are in the
  esterified form and less digestible than those in
  the free form (stems and leaves).

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Carotenoids

• Carotenoids are found in the diet in the free
  form or esterified to fatty acids.
• Most carotenoids in fruits and seeds are in the
  esterified form and less digestible than those in
  the free form (stems and leaves).
• Carotenoid esters must be hydrolyzed by specific
  intestinal esterases prior to absorption, this is
  a rate-limiting step.

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Carotenoids

• Factors which influence fat digestion will also
  influence carotenoid digestion.
• Each carotenoid appears to have its own
  individual pattern of absorption, plasma
  transport, and metabolism.
• Species differences in types of carotenoids that
  are preferentially absorbed, metabolized.

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Carotenoids

• Canaries, chickens efficiently absorb and
  utilize xanthophylls to pigment tissues but do
  not efficiently absorb B-carotene and metabolize
  it to the appropriate xanthophylls.
• Flamingos effectively absorb and utilize
• B-carotene as a precursor for skin and feather
  pigments but no not readily utilize many other
  dietary xanthophylls.

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Carotenoids

• In some species, the deposition of specific
  carotenoids into newly synthesized tissue may
  differ within different parts of the body.
• -different feather colors, skin pigments

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Carotenoids

• In some species, the deposition of specific
  carotenoids into newly synthesized tissue may
  differ within different parts of the body.
• -different feather colors, skin pigments
• Some species are not very specific in the type
  or quantity of carotenoids absorbed. The color
  of a chickens skin, adipose, and egg yolk are
  directly reflective of the type and level of
  dietary xanthophyll.

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Carotenoids

• Changing the proportion of specific xanthophylls
  can change the color of yolks from lemon yellow
  to golden yellow to orange-red.

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Carotenoids

• Changing the proportion of specific xanthophylls
  can change the color of yolks from lemon yellow
  to golden yellow to orange-red.
• Xanthophylls in feed or tissues loses their color
  after oxidation so adequate antioxidants help
  maintain pigmentation potential.

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Carotenoids

• Changing the proportion of specific xanthophylls
  can change the color of yolks from lemon yellow
  to golden yellow to orange-red.
• Xanthophylls in feed or tissues loses their color
  after oxidation so adequate antioxidants help
  maintain pigmentation potential.
• The antioxidant activity of some carotenoids is
  superior to Vitamin E though distribution limits
  their functionality.

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