Source: Alberta Agriculture and Forestry
Why is Vitamin Supplementation required?
Vitamin A, D, and E, are fat soluble vitamins that are required in a properly balanced feeding program;
Vitamin A is important for bone development, sight, and soft tissue maintenance. Deficiencies can cause reduced fertility (longer to first cycle and lower first service conception rates). Fetal bone development and bone density in mature animals is reduced. Animals on feed can have a reduced feed efficiency and increased occurrence of disease and illness.
Vitamin D is provided by sunshine over the summer, and can be limited in the winter with shorter daylight hours. It is needed to prevent rickets, and to reduce the incidence of having weak, deformed or dead calves during the calving season.
Vitamin E is important to improve the efficiency of Vitamin A and selenium. It is important for immune and reproductive functions both in cows, heifers and bulls.
Do stored forages lose their vitamins?
Exposure of cut hay to the air for 60-90 days results in destruction of the fat soluble vitamins. This will occur in baled hay, silage, round bale silage, or feed that is going to be used for winter swath grazing. Supplementation is required at this time.
Are Fat Soluble Vitamins Stored by the animal?
Vitamins A, D, and E, can be stored in the liver and used by the animal for 2-3 months after coming off green pasture.
How can Vitamins be supplemented?
Vitamin A and D can be given by injection, and will last about 2-3 months. Injections should be done twice during the winter months. Typically vitamin A and D are together in one solution with only enough vitamin E present to prevent deterioration of the two vitamins. There is no registered product for vitamin E injection in Canada.
Forced feeding of vitamins in a grain mix or in a silage based ration is the preferred method of providing vitamins to livestock. Each animal will obtain some vitamin everyday.
Free choice supplementation of vitamins through a free choice mineral supplement, protein lick or block, or in a salt/mineral/vitamin mix is not consistent. Variability of intake both on a daily basis and a grams/head/day can create deficiencies and excesses. Intake must be monitored to ensure proper supplementation levels.
What levels of Vitamin supplementation are required?
Age and size of the animal, stage of production (pregnant vs lactating) and health status of the animal all influence vitamin requirements. High stress situations generally increase vitamin requirements, ie. weaning, calving, or weather change.
Refer to published values or talk to your feed salesman or nutritionist to develop a solid vitamin supplementation program.