EFFECT OF MINERALS & ESSENTIAL VITAMINS ON MILK PRODUCTION AND REPRODUCTION IN DAIRY COWS

Introduction

Minerals are one of the key components of any dairy animal diet. These are generally inorganic as neither comes from either plant or animal origin and plays a very important role in growth as well in vital muscle and nervous functions. There are number of essential minerals which are required for maintenance, growth & reproduction.

Minerals required in large amount are classified as macro minerals and this includes mainly calcium, phosphorus, sodium, chlorine, potassium, magnesium & sulphur.

Calcium in one of the most important minerals, about 98% of it is present in bone and teeth. For dairy animal as it plays a role in bone and teeth formation, blood clotting, muscle contraction, regulation of heart beat, nervous impulse & most importantly its contribution in whole milk is as high as 12 %.

With the initiation of lactation and continued milk production, tremendous adaptations occur in the dairy cow because of the increased need for nutrients to support milk synthesis. Besides the increased need for energy and amino acids for colostrum and afterward for milk synthesis, the requirement for calcium increases two to three fold over & above what required by the dairy cow before calving.

The concentration of calcium in blood is tightly regulated through control of absorption of dietary calcium and release or uptake of calcium from bone. Two hormones, parathyroid hormone (known as PTH) and 1,25-dihydroxy vitamin D₃, control these processes.  As the concentration of calcium decreases in the blood, PTH is secreted and acts at the kidney to decrease the excretion of calcium in the urine. This change allows for only small adjustments in the concentration of blood calcium. If greater amounts of calcium are needed, as with the initiation and maintenance of lactation, PTH acts on bone, and calcium is reabsorbed and released into the blood. In addition, PTH acts on the kidney and results in the conversion of a vitamin D metabolite into 1,25-dihydroxy vitamin D₃. Then 1,25-dihydroxy vitamin D₃ can regulate the absorption of calcium from the small intestine through active transport.

Deficiency of calcium can leads to various problem such as rickets, poor bone growth, milk fever, reproductive disorder and lastly decrease in milk production.

Phosphorus is the second most abundant mineral element in the body with 80 to 85% of phosphorus in the body being found in the teeth and bones. Phosphorus is involved in every metabolic reaction & energy transfer within the body & required for normal milk production, growth, and efficient use of feed by the rumen microorganisms in the digestion of cellulose & synthesis of microbial protein.

In deficient cattle, growth rates, voluntary feed intake, feed efficiency and reproductive efficiency are decreased. In extremely deficient cattle, bone mineral content is decreased and the bones started to break very easily. The key for preventing phosphorus deficiencies is to consistently provide adequate amounts of phosphorus. This means the complete mineral supplement needs to contain the appropriate concentration of phosphorus and cattle need to consume adequate amounts of the mineral supplement. Various types of studies done with supplementation of oral calcium have proved overtime that it has significant effect on milk production as well as on reproductive health.

Mode of Action

The high degree of regulation of calcium homeostasis in the cow maintains plasma calcium at an adequate level in most situations, and as long as the regulatory systems are functioning, plasma calcium level is maintained independent of dietary calcium level.

Oral calcium supplemented has shown a positive response for preventing a drop in concentration of blood calcium. Oral Calcium get absorbed within 30 minutes after administration and blood calcium concentration is increased for 4 to 6 hours.

The unique combination of Oral Calcium with phosphorous, Vitamin D3, Vitamin B12, Vitamin E, Vitamin A increase the absorption as well utilization of these minerals and vitamins.

The availability of dietary calcium for absorption varies with dietary source which makes the chelated & organic form getting absorbed more effectively. Also chelated minerals ensure higher bioavailability (1.2-1.85 times higher than inorganic) as these are protected from ruminal microflora, pH and enzymes of GI tract hence animal get sufficient amount of calcium, phosphorous and other vitamins present in oral calcium.

One crucial benefit of Mineral supplementation is in preventing heavy metal interaction like Lead, mercury, cadmium etc. Heavy metals are toxic to animals even in small level and they interact with other essential macro and micro minerals and make them unavailable and hence animal suffer from severe deficiency. Various type of analysis has revealed the presence of these heavy metals in Mineral mixture as these come into mineral premix from the ore from where minerals are collected.

Phosphorus is also a vital mineral that is required by the animal body. It plays a key metabolic role and has more physiological functions than any other mineral. These functions involve major metabolic processes such as: tissue and bone development, development and maintenance of skeletal tissue, maintenance of osmotic pressure and acid base balance, energy utilization and transfer, Protein synthesis, transport of fatty acid and amino acid exchange. Phosphorus compounds are involved, directly or indirectly, in all major physiological functions and therefore play part in or rather are responsible for intestinal absorption, glycolysis and direct oxidation of carbohydrates, renal excretion, transport of lipids, exchange of amino acids, etc. Phosphorus is also a component of a large number of coenzymes.

Various studies have proven that supplemental vitamin B12 found to be beneficial for milk production and milk component yields for high producing dairy cows in early lactation 

Vitamin B12 is an essential part of several enzyme systems that carry out a number of basic metabolic functions. Most reactions involve transfer or synthesis of one-carbon units, such as methyl groups. Vitamin B12 is metabolically related to other essential nutrients, such as choline, methionine and folic acid. Although the most important tasks of vitamin B12 concern metabolism of nucleic acids and proteins, it also functions in metabolism of fats and carbohydrates.

Milk production is also dependent on vitamin A. In vitro studies show important interactions among vitamin A, lactoferrin, and insulin-like growth factor (IGF) binding proteins. As a consequence vitamin A is important for mammary gland epithelial cell proliferation and apoptosis during the dry period and potential milk yield can be affected. There are reports of improved mammary health in dairy cows supplemented with vitamin A during the dry period and lactation. Vitamin A is required for normal visual function, maintenance of healthy epithelial tissues and mucous membranes, normal bone development and functional immunity in animals. Clinical signs of vitamin A deficiency may be specific or nonspecific. General signs observed include loss of appetite, loss of weight, unthrifty appearance, thick nasal discharge and reduced fertility. The normal epithelia of the body are progressively replaced by stratified, keratinized tissue. This effect has been noted in the respiratory, alimentary, reproductive and genitourinary tracts as well as in the eye. Keratinization reduces the effectiveness of the epithelial tissues as a barrier to the entrance of infectious organisms. Thus, respiratory and upper respiratory diseases tend to be more severe in animals with vitamin A deficiency.                                              

Vitamin E has been shown to be essential for the integrity and optimum function of reproductive, muscular, circulatory, nervous and immune systems in animals. Vitamin E is highly effective in reducing toxicity of silver, arsenic, nickel and lead, and shows slight effects against cadmium and mercury toxicity.

Heavy metals produce oxidative damage to tissues, and thus vitamin E can exert a protective antioxidant effect. Vitamin E can be effective against other toxic substances.

Beneficial effects of supplemental vitamin E for dairy cows include reduced incidence of reproductive disorders, reduced clinical mastitis and somatic cell count & finally protection of milk from oxidation 

The high plasma level for longer period also helps those animals having increased demand due to increased milk yield or due to any kind of stresses. The balanced level of calcium & phosphorous in oral calcium helps in maintaining the actual ratio required by the animal for these two important minerals i.e. 2:1.

Conclusion

Feeding the proper amounts of all minerals and vitamins is very important for profitable milk production from healthy cows.If your Lactating cow as well dry cows and heifers are not getting minerals make sure they are getting Oral Calcium Combination with other Minerals & Vitamins, as this will help in there lactation phase as well as in preparation for next lactation and reproductive health..