Information About Vitamin D...

It is a vitamin with rickets activity.
Vitamin D precursors;
Ergocalciferol in plants,
In animals it is 7-dehydrocholesterol.
Vitamin D has two types, cholecalciferol (Vitamin D3) and ergocalciferol (Vitamin D2).
The pro-vitamin of Vitamin D2 is ergosterol and Vitamin D3 is 7-dehydrocholesterol.
Vitamin D2 is found in plants and yeasts and vitamin D3 is found in animal tissues. 
Vitamin D of animal origin (vitamin D3 or cholecalciferol) is formed as a result of UV light exposure of 7-dehydrocholesterol formed from cholesterol in animal tissues.

Vitamin D, which is ingested in the diet or formed in the body, reacts first in the liver and then in the kidney and then acts on the target tissues and organs.

Leguminous grasses contain vitamin D when they are properly recovered by exposure to natural or artificial UV light.  Alpha alpha contains 660-3300 U/kg of vitamin D. This amount varies according to processing or storage conditions.

Ergosterol, the precursor vitamin of vitamin D2, is found in plants.

In both plants and animal tissues, the formation of vitamin D2 and vitamin D3 from ergosterol and 7-dehydrocholesterol, respectively, is weakened due to the short days in winter, weakening of sunlight due to fog-clouds, etc., and the impermeability of windows to UV light in cloudy and closed places.

Vitamin D is well absorbed from the digestive tract.

Bile acids are needed for absorption. Disorders related to liver and bile secretion impair absorption.

It is stored in the body for a long time in tissues, especially in fat tissue.  Small amounts of vitamin D are found in kidneys, adrenal glands, bones and intestines.

Vitamin D;

Absorption of minerals from the intestines in mammals and poultry

Providing and maintaining blood calcium, phosphorus and phosphotase balance

It is a substance with functions related to growth rate, bone formation and reproduction.

Vitamin D accelerates the absorption of calcium and phosphorus from the intestines.

While Vitamin D accelerates bone formation in young people, it enables the renewal of old bone tissue in adults.

Vitamin D maintains calcium and phosphorus within normal limits for nerve stimulation, ossification, blood clotting and other calcium-dependent events.

The reabsorption of calcium from the intestines and kidneys by the effects of vitamin D and para hormone, and the increased release of calcium from old and old bones ensure that the plasma calcium-phosphorus balance remains within normal limits.

Vitamin D deficiency leads to rickets in young people and osteomalacia (osteoporosis, adult rickets) in adults.

In rickets, blood calcium and phosphorus levels decrease and ossification deteriorates.

In the disease, long bones bend, joints become stiff and swollen. Frequent fractures occur.

The disease is mostly encountered in calves, lambs, kids and wings.

In case of deficiency, the disease in adults is osteomalacia.

In adults, calcium and phosphorus are separated from the bones and their ratios in the bones decrease in case of a significant impairment of calcium absorption and a significant increase in the need, such as pregnancy or milking. bones soften and deformities develop.

In cattle;

The first noticeable symptom of rickets is swelling in the joints. Although cartilage ends continue to develop in the bones, these parts cannot be converted into normal bone tissue. As the disease progresses, the front legs can be bent up to the knees. The joints are stiff and swollen. Bone fractures are frequently encountered. Sick animals usually have a drawn abdomen and hunched back.

Respiration is accelerated and they become exhausted even after light exercise. they are restless. They have lost their appetite and are weak. They can stand by crossing their hind legs and walk by dragging their hind legs.

The joints of the ribs become enlarged and swollen like rosary beads. In severe cases, death by convulsions is seen.


In poultry, developmental retardation, reluctance to walk, softening and sponging of the beak, failure to develop the sternum and curvature of the spinal canal are observed.

In laying hens, first the eggshell becomes thinner and then the egg yield decreases.

The breast bones become soft and spongy. leg and wing bones are easily broken.

The hens gradually lose the use of their legs and typically squat or sit on the ground. This condition is known as egg preference.

The hatching rate is also significantly reduced.

Vitamin D is used for the prevention of birth paralysis.

Vitamin D to be used in treatment should be several times the preventive dose.

Vitamin D to be used in the treatment of rickets should be 10-15 times the daily requirement.

Especially during the autumn and winter months and in weather that does not receive enough sunlight, animals should be given vitamin D-supplemented feeds.