Niacin (Vitamin B3)
Niacin (Vitamin B3) deficiency is very important in pig and dog
Corn is deficient in Niacin or Vitamin B3
Deficiency of Niacin or Vitamin B3 causes canine pellagra and swine pellagra
Pellagra results from deficiency of Niacin or Tryptophan
In swine it causes nutritional enteritis or chronic diarrhea
Deficiency of Vitamin B3 causes mucus degeneration and then causes invasion by Salmonella cholerasuis, Sherophorus necrophotus and Balantidium coli and causes diffuse 
Niacin (Vitamin B3) deficiency in dogs cause black tongue/Canine pellagra
Pyridoxine (Vitamin B6)
Three naturally occurring forms. i. Pyridoxine	ii. Pyridoxal	iii. Pyridoxamine
Abundant in cured grains
Coenzyme form of Pyridoxine is Pyridoxal S Phosphate involved in transaminations, carboxylations, deaminations in lipid and aminoacid metabolism
Deficiency of Vitamin B6 causes microcytic anaemia in swines
Deficiency of B6 causes haemosiderosis of spleen, liver, bone marrow
Necrosis and atrophy of dorsal root ganglia in swine

Pantothenic acid or B5
Chick antidermatitis factor
Deficient in corn so deficient ion corn fed to swines
Pantothenic acid is an important component of Coenzyme A
Pantothenic acid is important precursor of cholesterol, steroid hormones
Pantothenic acid is deficiency in swine leads to alopecia, rough hair coat, Goose stepping gait (pigs drags with hind legs)

Biotin
Hypobiotinosis: Kangaroo sitting posture haunched stance
Present in green plants, liver, yeast
Biotin synthesized in rumen and large intestine
Biotin deficiency mainly seen in poultry (synthesized in caecum and absorption from SI so deficiency in birds)
Aflatoxin is a Biotin antagonist
Biotin is an important cofactor for pyruvate carboxylase
Acetyl coenzyme A carboxylase (in lipogenesis)
Biotin is essential in Carbohydrate and lipid metabolism
Avidin in egg (raw) causes Biotin deficiency
Biotin deficiency causes parrot beak and chondrodystrophy or bone abnormality in birds. Also causes perosis or slipped tendon
Biotin deficiency causes fattly liver kidney syndrome (FLKD)
Vitamin B9 or Folic acid (folate)
Folate is the naturally occurring form of vitamin B9
Folic acid is a synthetic form of vitamin B9, also known as pteroylmonoglutamic acid.
Chemically folic acid is Pteroylmonoglutamic acid  
Rich in greens, fruits, vegetables etc
Folic acid is mainly transported as monoglutamate
Folic acid within the cell is converted to tetrahydrofolate
Folic acid is essential for cell mitosis
Folic acid deficiency reduces DNA synthesize
Folic acid deficiency causes Megaloblastic anaemia (Co deficiency also cause Megaloblastic anaemia)

Vitamin B12 (Cyanocobalamine)
Vitamin B12 has the most complex structure of all vitamins
Synthetic therapeutic form of B12 is Cyanocobalamine
Ruminants synthesise B12 in rumen by microbes
Cobalt is needed for Vitamin B12 synthesise
Deficiency of Cobalt causes B12 deficiency in ruminants
Vitamin B12 deficiency is very important in poultry
Vitamin B12 is very essential for nucleic acid synthesise and for good health of nervous system
Deficiency of Cobalt and Vitamin B12 causes Ovine white liver disease
Diphyllobothrium latum depletes Vitamin B12 in host and it results in pernicious anaemia
Vitamin B12 closely connected with folic acid in its functions
Vitamin B12 deficiency causes DNA synthesize impairment
Vitamin B12 deficiency causes Megaloblastic anaemia
Vitamin B12 deficiency causes oedematous and haemorrhagic embryo

Vitamin B4 or Choline
Choline is CH3 (Methyl) group donator for various reactions
Choline helps in converting neutral fat to phospholipid
Choline deficiency causes Fatty change
Choline is called as Lipotropic factor as it is having fat affinity
Fatty liver of young animals due to choline deficiency
Colustrum is a good source of Choline
In poultry its deficiency causes fatty liver, decreased hatchability, chondrodystrophy etc

Vitamin C or Ascorbic acid
Rich in greens, fruits, citrus fruits (highest amount of Vitamin C)
Most animals produce Vitamin c from glucose via glucuronic acid they have L-gulonolactone oxidase
Humans, Guinea pigs and monkeys lack L-gulonolactone oxidase enzyme so has Vitamin C deficiency
Ascorbic acid or Vitamin C produced in liver of mammals and birds
Kidney also synthesize Vitamin C in certain birds
Vitamin C is important in accelerating hydroxylation reaction
Most important function of Vitamin C is cofactor of Prolyl and Lysyl hydroxylation of Proline and Lysine
Collagen has highest content of Hydroxyproline in the body
Vitamin C is very important in collagen synthesise. So cause scurvy in man, monkey and guinea pigs
Deficiency of Vitamin C causes haemorrhages mainly in gums
Wound healing also affected in Vitamin C deficiency