Vitamin supplementation in high-producing dairy cows

Diets formulated with vitamins should be used according to the animal's needs, which vary depending on the species and category. It must be taken into account that roughage does not always meet nutritional needs, especially

10.11.2015 | 21:59 (UTC -3)

1. Introduction

Dairy production systems currently face several problems mainly related to quality parameters and reproduction. Alternatives to meet energy demand are fundamental for good production, which must meet energy needs and contain adequate levels of proteins, vitamins and minerals. Any imbalance in the diet can lead to a decrease in productive and reproductive performance, generating economic losses.

Vitamins are present in foods in small quantities and are essential in the nutrition of dairy cows, as they participate in different processes in maintaining health, growth and reproduction. Like any nutrient, they must be present in the diet in correct quantities, preventing hypovitaminosis, caused by a lack of these substances, or hypervitaminosis, resulting from an excess of them. Vitamin supplementation in the feed, in mineral form, guarantees a better response to the dairy potential, and helps in maintaining the clinical state, preventing diseases such as mastitis and other common illnesses in the period.

Diets formulated with vitamins should be used according to the animal's needs, which vary depending on the species and category. It must be taken into account that roughage does not always meet nutritional needs, especially stored products (silage and hay), which lose their nutritional concentration over time. Ruminants are different from other animals because they have the ability to synthesize many water-soluble and fat-soluble vitamins through the rumen.

Therefore, it is important to know the specific functions of vitamins, their benefits and deficiencies, to understand how and when they should be supplemented.

2. Fat-Soluble Vitamins

2.1 Vitamin A

It is a fundamental nutrient for the integrity of the mucosa of animals and their reproductive system, participates in the transformation of reproductive hormones and plays an important role in the development of the nervous and immune system. Its lack develops problems in several systems; on the skin, the hair becomes rough; in the eyes, night blindness and retinal degeneration can occur; in the nervous system there is disordination of movements, convulsions and nervous degeneration; in the respiratory system, they increase sensitivity to respiratory tract infections; the digestive system becomes more sensitive to mucous infections; in the reproductive system there is atrophy of the ovaries with a low ovulation and fertilization rate, in addition to problems with the estrous cycle and retained placenta. Vitamin A poisoning does not represent a problem in practical conditions, as it does not occur in plants but rather in its precursors.

2.2 Vitamin E

Found in oilseeds, related to various functions in the body, vitamin E has an important antioxidant role, delaying aging and preventing premature degeneration. Its supplementation associated with Selenium has shown good rates of reduction in mastitis and intramammary gland infections. It has a specific action on the absorption of vitamin A and its storage in the liver, so the deficiency of both is concomitant and can generate a series of problems, especially in young animals, where white muscle disease (abnormal calcification of muscles) is a classic sign, in addition to nutritional muscular dystrophy, which attacks skeletal and cardiac muscles. The deficiency may arise from inadequate intake and low availability of the vitamin in food, due to inadequate processing conditions. Vitamin E does not present toxicity due to its low absorption.

2.3 Vitamin D

It acts on the metabolism of calcium and phosphorus, providing better absorption of these minerals by the intestinal mucosa, having an important influence on bone mineralization and mobilization of these minerals from the bones. Its deficiency in the body compromises the bone system, deforming it, and increases the risk of milk fever. The deficiency may have occurred due to inadequate intake or little exposure to sunlight, necessary for the conversion of vitamin D precursors. Intake of high levels of vitamin D, for long periods, can cause a reduction in food intake, and thus in the rate of growth and production.

2.4 Vitamin K

The main function played by vitamin K is in the synthesis of proteins in the rumen and in its anti-hemorrhagic role. Its deficiency is difficult to occur, as it is synthesized within the digestive tract by ruminal bacteria, but when it occurs, it triggers an increase in blood clotting time.

3. Water-soluble Vitamins

3.1 B complex vitamins:

They are synthesized by the rumen flora, which is why the deficiency generally occurs in calves because they do not have a developed rumen. It can also happen that high doses of antibiotics lead to deficiency, as they weaken rumen microorganisms, compromising the adequate composition of rumen microflora.

Its functions are linked to the nervous system, performed by Thiamine-B1 (wheat bran and alfalfa) and Choline. Niacin-B3 acts in the formation of blood cells. Riboflavin-B2 acts to detoxify the liver in cases of excess urea intake. Pantothenic Acid-B5 acts in the formation of the animal organism's immune system, and in the formation of vitamin A, from carotenes. Pyridoxine-B6 acts in the formation of proteins from amino acids. Biotin-B7 and Folic Acid-B9 act on cell growth and strengthening.

3.2 Vitamin C:

Also known as ascorbic acid, vitamin C acts as an antioxidant, preventing aging and degeneration of the body's cells and helping to absorb fats. Deficiency of this vitamin is characteristic of humans, and is rarely reported in ruminants.

4. Vitamin requirements in dairy cows

All animals have vitamin needs, but supplementation for ruminants is different due to their digestive tract. The production of vitamins from the B complex and vitamin K occurs during the degradation and fermentation of nutrients present in the rumen microbiota, however, in high-production cows, due to the productive capacity that accelerates the body's reactions during lactation, there can be a greater susceptibility to vitamin deficiency.

Vitamin D is synthesized through sunlight on the skin, and vitamin C from sugars. Thus, simple measures maintain the needs for vitamin B, C, D and K, such as exposing animals to sunlight for a few hours and a balanced diet, which promotes the synthesis of vitamins in the rumen.

For these reasons, exogenous vitamin supplementation in ruminants basically consists of Vitamin A and E. In certain circumstances, deficiencies of vitamins D and thiamine can occur in animals raised in stables, respectively due to the absence of sunlight and the provision of high levels of feed. , which cause a drop in pH and a decrease in microorganisms in the rumen. In high-production cows, niacin supplementation is necessary, as ruminal microorganisms do not meet physiological needs.

It is difficult to define vitamin requirements, as they change depending on the category (dry cow and peripartum cows). In the pre-partum period, the concentration of vitamin A reduces by 38% and α-tocopherol (provitamin E) decreases by 47%, this sudden drop coincides with the period of drop in dry matter intake and with the synthesis of colostrum, which is highly rich in fat-soluble vitamins. This variation compromises the cow's immune system and results in an increase in infectious diseases.

The NRC (diet formulation program) considers that vitamin A should be supplemented at 110 IU/kg, even though it is present in food fed to animals. In lactating cows fed with preserved forage, the required amount of vitamin E is 0,8 IU/Kg (NRC 2001).

When choosing a mineral enriched with vitamins for his dairy herd, the producer must pay attention to the following characteristics required by the Ministry of Agriculture, Livestock and Supply (MAPA):

• Supplements must indicate their quantities per kilogram of product – in IU (international units) for vitamins A, D and E, for vitamin B-12 in micrograms and in milligrams for the other vitamins.

• Supplements must have the minimum content in the final mixture as shown in Table 1:

5. Tips to avoid loss of vitamins from food

The concentration of vitamins in forage is highly variable, basically depending on factors such as the origin of the forage; climatic condition and stage of maturity of the plant. However, some care at the time of conservation and storage conditions can guarantee a smaller variation in vitamins between harvest and until it is supplied to the animals.

The levels of β-carotene (provitamin A) and α-tocopherol (provitamin E), found in grasses and legumes, are high in the initial stage and reduced at the maturity of the plant, making cutting recommended at the initial stage. The green color of the plant is a good indicator of its carotene content. After cutting the plant, excessive exposure to sunlight should be avoided, as they increase the destruction of vitamin D and β-carotene and α-tocopherol. In this case, drying in the barn should be chosen to reduce the destructive effect.

The presence of humidity can aggravate the loss of β-carotene during the drying process. When forage is exposed to rain and then dried in the sun, vitamin losses increase compared to forage dried only in the sun. In the case of B vitamins and β-carotene (provitamin A), the losses are complete.

The vitamin content after the haymaking process is largely reduced compared to fresh forage; after 28 weeks of storage, the β-carotene content in hay is close to zero. The factors that may be involved in these losses are humidity, high temperature in the silo and the presence of light. Ensiling grasses and legumes presents less loss of β-carotene and α-tocopherol compared to haymaking. However, when additives and organic acids are used, the loss of vitamins is greater.

6. General considerations

A diet that meets vitamin requirements should be a concern for both small and large producers, as small imbalances in nutritional requirements can cause losses, through a reduction in milk production and, in more serious situations, deficient diseases that can even lead to loss. of the animal. In this case, it is recommended to use vitamin complexes, injectable or oral, for a quick recovery of the animal. Care must be taken because, contrary to what the leaflet states, excessive dosages can cause damage, even leading to intoxication. To correctly establish the supplement and the dosage to be applied to the animal, the veterinarian must be consulted and provide support during supplementation therapy.

The producer can guarantee a better supply of vitamins for his animals through careful conservation and choice of forage that is being used on his dairy property. However, the most commonly used form of supplying vitamins, due to their practicality, is through supplements, which must meet MAPA's requirements.

Guilherme Nunes Bolzan – Graduating in Veterinary Medicine

Paula Montagner – Graduate in Veterinary Medicine

Augusto Schneider – PhD student in Biotechnology

Rubens Alves Pereira – Master’s student in Biotechnology

Ivan Bianchi – Doctor in Agricultural Biotechnology

Marcio Nunes Corrêa – PhD in Biotechnology

Center for Research, Teaching and Extension in Livestock

Check out this article, with table, at the link below:

7. Bibliographic References

NICODEMO M, L. Suitable minerals (on line). Available in:

Accessed on August 24, 2009.

ROCHA M, V, F. Normative instruction nº 152, of October 11, 2004 (online). Available in

Accessed on August 23, 2009.


Accessed on August 23, 2009.

Santos J, E, P and SANTOS F, A, P. New Strategies in the Management and Feeding of Pre-Calving Cows. Available in

. Accessed on August 18, 2009.

GONZÁLEZ F. H. D.; SILVA S.C.; Introduction to veterinary clinical biochemistry, 2nd edition; Porto Alegre: Editora da UFGRS, 2006.

ZEOULA M, L.; GEROM L, J, V.. Vitamins. In: BERCHIELLI T.T.; PIRES, A. V.; OLIVEIRA, S. G; Ruminant Nutrition, Jaboticabal/ FUNEP –São Paulo, 2006.

PASCHOAL J.J.; ZANETTI M.A.; Effect of vitamin A supplementation on the incidence of mastitis in Holstein cows. Brazilian Archive of Veterinary Medicine and Zootechnics, v.56, n.2, p.267-269, 2004 .


. Accessed on August 18, 2009.

GASPAR R.M.; COSTA R. S., Mineral Nutrition for Dairy Cattle. Available in

Accessed on August 18, 2009.

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