Special Veterinary Pathology

Vitamin B complex - Vitamin B1

VITAMIN B COMPLEX

• Coenzymes in Kreb’s cycle
• Also called as “energy releasing vitamins”
• Synthesised in rumen except in young animals
• Water soluble
• Found in yeast

VITAMIN B1/THIAMINE (ANTI–NEUROTIC/ANTI BERI BERI FACTOR )

Sources

• Whole grains and meat
• Milled and polished

Functions

• Component of thiamine pyrophosphate
• Essential for synthesis of acetylcholine
• Nervous system greatly affected in deficiency
• Utilisation of lactic acid produced during carbohydrate metabolism

DEFICIENCY OF THIAMINE

Causes

• Presence of thiaminases in feed ingredients
• Increased temperature and increased requirements in birds
• Vitamin is destroyed by thiamine anlogues like amprolium
• Destruction of vitamin due toaction of thiaminases found in certain fishes
• Increased coccidiostats and coccidiosis in birds
• In ruminants thiamine is synthesized in forestomach
• But in young animals dietary supplementation is essential

Poultry

• Clinical signs
• Increased feeding of milled products and low greens feeding
• Loss of appetite
• Polyneuritis
• Paralysis starting from toes
• Bird sits on its flexed legs and retracts its head called “STAR GAZING ATTITUDE”
• Lesions

  • Degeneration of peripheral nerves
  • Atrophy of heart muscle

Pigs

• Cardiac dilatation and myocardial necrosis
• Sudden death

Humans

• Causes “BERI BERI”
• Due to eating polished grains
• Charecterised by peripheral neuritis, oedema, myocardial weakness

“Chastek paralysis’’

• Cats and foxes fed with raw fish containing thiaminase
• Degeneration and necrosis of neurons causing paralysis

Horses

• Fed with thiaminase containing feed like brackern fern, horse tail causes incoordination and bradycardia