Vitamins are usually provided in premixes. Although vitamins are only required in small amounts in the diet, they are considered essential and their effects on animal performance are huge. Vitamins are not just building blocks or energy-yielding compounds but are also involved in many of the biochemical pathways in the body.
Vitamins can be divided in two main groups: fat-soluble (Vitamins A, D3, E, and K) and water-soluble (the B Vitamins and Vitamin C).
Vitamin A
Vitamin A, one of the fat-soluble vitamins, is chemically known as retinol.
Vitamin A does not exist in plants as such but is present as precursors or provitamins in the form of certain carotenoids which can be converted into Vitamin A. Carotenoids are divided into two categories; carotenes and xanthophyll’s. Most xanthophyll’s cannot be converted to Vitamin A, but B-carotene is the main source of vitamin A in the diets of farm animals.
Vitamin A accumulates in the liver and this organ is likely to be a reliable source, but the amount present differs per species and diet.
Vitamin A plays a significant role in sight, as well as in the formation and protection of epithelial tissues and mucous membranes.
Deficiency symptoms in:
Pigs
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Xerophthalmia (drying of the conjunctiva) and blindness
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Weak, blind or deformed litters
Cattle
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Excessive watery eyes, softening and cloudiness of the cornea. Development of xerophthalmia
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Blindness in calves
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Higher infertility rates and occurrence of abortions
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Roughened hair and scaly skin
Poultry
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High mortality rates
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Retarded growth, weakness
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Ruffled plumage
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Reduced egg production and hatchability
Horses
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Night blindness
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Keratinization of skin and cornea
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Susceptibility to infection and infertility
Vitamin D
Vitamin D3 (cholecalciferol), also one of the fat-soluble vitamins, is limited in distribution. Vitamin D3 rarely occurs in plants, except in sun-dried roughages and the dead leaves of growing plants. In the animal kingdom it occurs in small amounts in certain tissues and is only abundant in certain fish.
Vitamin D3 increases intestinal absorption of calcium and phosphorous from the intestine.
Deficiency symptoms in:
Pigs
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Enlarged joints, broken bones, stiffness of joints and occasional paralysis
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“Rickets” in your animals. A disease of the growing bone in which the deposition of calcium and phosphorous is disturbed
Cattle
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“Rickets” in your animals. A disease of the growing bone in which the deposition of calcium and phosphorous is disturbed
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Swollen knees and hocks and arching of the back
Poultry
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Rubbery bones and beaks
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Reduced egg production reduces
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Poor egg shell quality
Vitamin E
Vitamin E (α-tocopherol), unlike vitamin A, is not stored in the animal’s body in a large amount but is fortunately widely distributed in foods such as green fodders and cereal grains.
Vitamin E functions in the animal as a biological antioxidant and protects cells against oxidative damage caused by free radicals. Furthermore, it also plays a significant role in the development and functioning of the immune system.
Deficiency symptoms in:
Pigs
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Myopathy
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Cardiac disease (mulberry heart disease)
Ruminants
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Nutritional muscle degeneration (myopathy) in calves (white muscle disease) and lambs (stiff lamb disease).
Poultry
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Myopathy
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Encephalomalacia (crazy chick) – chick is unable to walk or stand and is accompanied by hemorrhages and necrosis of brain cells.
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Exudative diathesis – general oedema of the subcutaneous fatty tissues
Horses
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Lameness
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Muscle rigidity
Vitamin K
Vitamin K is necessary for the synthesis of prothrombin in the liver and plays a significant role in the blood clotting process.
Deficiency symptoms in:
Poultry
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Anemia
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Birds are easily injured and may bleed to death
Vitamin B1 (Thiamin)
Vitamin B1 is highly water soluble and is widely distributed in foods. It is concentrated in the outer layers of seeds, the germ and the growing areas of roots, leaves and shoots. Fermentation products such as brewer’s yeast, are also rich sources.
Deficiency symptoms in:
Pigs
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Adversely affected appetite and growth
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Vomiting
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Respiratory troubles
Poultry
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Poor appetite with consequent retardation in growth
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After 10 days with thiamin deficiency chicks may develop polyneutritis (progressive dysfunction of the nervous system)
Vitamin B2 (Ribovlavin)
Vitamin B2 is only sparingly soluble in water. It can be synthesized by all green plants, yeasts, fungi and most bacteria. Rich sources are yeasts, liver, milk and green leafy crops. Cereal grains are poor sources. It plays a vital role in carbohydrate and amino acid metabolism
Deficiency symptoms in:
Pigs
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Poor appetite with consequent retardation in growth
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Vomiting
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Skin eruptions
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Eye abnormalities
Ruminants
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Symptoms more likely in calves and lambs – loss of appetite, diarrhea and lesions in the corners of the mouth
Poultry
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Poor growth in chicks
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Develop curled toe paralysis
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Reduced hatchability
Nicotinamide
Niacin plays a vital role in energy metabolism and enhances protein synthesis. Rich sources are liver, yeast, groundnut and sunflower meals. Cereal grains are poor sources.
Deficiency symptoms in:
Pigs
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Poor growth
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Anorexia
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Enteritis
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Vomiting
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Dermatitis
Cattle (Dairy cows)
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Higher incidence of ketosis in early lactation
Poultry
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Bone disorders
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Feathering abnormalities
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Inflammation in the mouth
Vitamin B6 (Pyridoxine)
Vitamin B6 is important in protein metabolism and red blood cell formation. Seldom deficient except when feeding linseed meal.
Deficiency symptoms in:
Pigs
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Convulsions
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Dermatitis
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Impaired reproduction
Pantothenic Acid
Pantothenic acid has an important function in acetate and fatty acid metabolism. This vitamin is widely distributed. Rich sources include liver, egg yolk, groundnuts, peas, yeast and molasses. Cereal grains are also a useful source.
Deficiency symptoms in:
Pigs
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Goose-stepping gait in swine
Poultry
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Reduced growth
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Dermatitis
Folic acid
Folic acid is widely distributed in nature; green leafy materials, cereals and extracted oilseed meals are useful sources. It plays a significant role in the synthesis of haemoglobin. It is also related to B12 metabolism. Folic acid deficiencies rarely occur in other farm animals because of synthesis by intestinal bacteria.
Deficiency symptoms in:
Pigs
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Impaired reproduction
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Decreased litter size
Poultry
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Anemia and poor growth.
Biotin
Plays an important role in carbon dioxide transfer and fat metabolism. It is widely distributed in foods, however in some foods much of the bound vitamin may not be readily available during digestion.
Deficiency symptoms to in:
Poultry
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Dermatitis and cracks in feet
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Poor growth
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Loss of feathers
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Poor reproduction
Choline
Sources include leafy materials, yeast, egg yolk and cereals are also rich sources. Choline is not a metabolic catalyst but forms an essential structural component of body tissues.
Vitamin B12 (Cyanocobalamin)
Vitamin B12, with Folic Acid, is responsible for the synthesis of haemoglobin. It is synthesized by the rumen in ruminants and is therefore essential in diets for swine and poultry.
Deficiency symptoms in:
Pigs
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Reduced growth
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Anemia
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Impaired reproduction
Poultry
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Reduced growth
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Anemia
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Poor reproduction and hatchability
Vitamin C (Ascorbic acid)
Vitamin C deficiencies seldom occur unless the animals are under stress.