Vitamin B2, also known as riboflavin, is an important vitamin for dogs. It acts as a precursor for FMN and FAD, which are cofactors in enzymes involved in energy production and metabolism. Signs of a deficiency include dermatitis, weight loss, weakness, and eye lesions like cloudiness or discharge. Riboflavin is found in many foods like meat, eggs, dairy and leafy greens. Dogs need around 2.2-5.3 mg of riboflavin per kg of diet daily to meet their nutritional needs.

1. Importance of
Vitamin B2 for
Your Pooch

2. HELLO!
I am Dr. Preethi Sudarshanie Dassanayake (B.
V. Sc., M.Sc., MBA) from Veterinary Teaching
Hospital, University of Peradeniya, Sri Lanka.
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3. Vitamin B2  Commonly known as riboflavin,Vitamin G ,
lactoflavin, hepatoflavin, & ovoflavin.
 Water-soluble.
 Yellow color organic compound.
 Easily destroyed by light.
 Heat stable.
 Roasting and steaming preserves more
riboflavin.
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4. o Riboflavin is d-Ribitol & it’s
hydroxyl group at position 5
is substituted by a 7,8-
dimethyl-2,4-dioxo-3,4-
dihydrobenzo[g]pteridin-
10(2H)-yl moiety.
o Formula –C17 H20 N4 O6
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Structure of
Riboflavin

5. FMN & FAD ◎ Riboflavin is present in the food as free
riboflavin, FAD & FMN.
◎ Riboflavin is a precursor of the two
coenzymes.
-Flavin mononucleotide (FMN).
◎ - Flavin adeno dinucleotide (FAD).
◎ - FMN & FAD are cofactors for several
enzymes (oxidoreductases) that present in
your pet.
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6. Chemical
structure of
Riboflavin,
FMN &FAD
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7. Digestion &
Absorption
Digestion & Absorption
• Protein bound riboflavin undergo proteolytic
digestion to release free riboflavin.
• FAD &FMN (phosphorylated forms) are
hydrolyzed by phosphatases to release free
riboflavin in upper small intestine.
• Riboflavin absorption enhances by bile salts.
• Free riboflavin is absorbed by mucosal cells
in the small intestine.
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8. Absorption &
Transport
◎ Absorption method is an active Na dependent
transport system.
◎ In the mucosal cells, riboflavin converts to
FMN by the enzyme flavokinase.
◎ FMN enters to the portal vein, bound with
plasma proteins (Albumin-FMN Complex)
transport to the liver.
◎ In the liver, FMN converts to FAD.
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9. Riboflavin,
FMN & FAD
◎ Riboflavin FMN
riboflavin kinase
ATP
FMN FAD
◎ FAD pyrophosphorylase
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10. Excretion
Excess riboflavin mainly excrete
through urine as free flavin.
Small amount of absorbed riboflavin
can be excreted through bile & sweat.
Storage
Due to water solubility cannot store
it considerably.
Riboflavin found in high
concentrations in liver, kidneys &
heart .
It is stored as FMN & FAD.
Approximately 1/3 of total body
riboflavin found in the liver.
Due to inability to store this vitamin, it must include with sufficient quantities in regular daily meals.
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Storage &
Excretion

11. Functions  Production of red blood cells.
 Supports production of antibodies.
 Helps prevent cataract.
 Supports energy production (ATP)by the
cells.
 Maintains mucus membranes healthy.
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12. Functions  Helps absorption of vitamin B6 &iron in the
intestines.
 Supports metabolism of fats, proteins &
carbohydrates.
 Supports conversion of tryptophan into
niacin.
 Helps activate vitamin B6 & folic acid.
 Acts as a coenzyme in many cells.
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13. Riboflavin
requirements
for dogs
◎ According to NRC (2006)- For all life stages
of dogs is 5.3mg per Kg of diet.
◎ The Association of American Feed Control
Officials (AAFCO, 2007) – For all classes of
dogs, 2.2mg per Kg of diet.
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14. Signs &
symptoms of
riboflavin
deficiency
Acute
 Anorexia.
 Weight loss.
 Hypothermia.
 Lethargy.
 Progressive
weakness.
 Ataxia.
 Collapse.
 Semicomatose.
 Death.
Chronic
o Anorexia.
o Weight loss.
o Flaky dermatitis
of the abdomen
and medial
surface of hind
legs.
o Ocular lesions.
Ocular lesions
o Generally
bilateral.
o Opacity of
cornea.
o Opacity of cornea
with
vascularization.
o Watery discharge
from the eye.
o Purulent
discharge from
the eye.
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15. Place your screenshot here
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Sources
Beef, Pork, Chicken,
Salmon, Trout, Dairy
products, Eggs,
Spinach, Kidney
beans, Cereals,Kale,
Broccoli.

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THANKS!
Any questions?
You can find me at
dassanayakepreethi@gmail.com.

17. CREDITS Special thanks to all the people who made and
released these awesome resources for free:
◎ Presentation template by SlidesCarnival
◎ Photographs by Google image.
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