Nutrition

• body weight of animals, respectively 2.5-3 kg DM / 100 kg live weight (LW);

• stage of lactation, respectively in the first third 2.8-3 kg DM / 100 kg live weight, in the second third 2.6-2.8 kg DM / 100 kg live weight and third 2.2-2.5 kg DM / 100 kg live weight;

• physiological state, respectively during the lactating period 2.5-3 kg DM / 100 kg live weight, in the mammary break period 1.6-2 kg DM / 100 kg live weight;

• number of lactation, respectively primiparas consume about 2 kg DM less than multiparas, because they have a lower body weight and lower milk production;

• energy requirements of cows, respectively in the case of increased requirements in energy of the animals in certain periods it is necessary an increase of dry matter consumption.

In order to meet the requirements of dry matter of diary cows, rations must meet three conditions, namely: adequate physical structure; optimum load factor; optimal rumen fermentation.

Lactating cows rations presents an appropriate physical structure when the fiber and coarse forages, minced or chopped at dimensions of 1 cm, are administered in quantities of at least 3 kg / head / day, favoring digestion and thus enhancing milk production. Finely chopped forages cause a reduction in milk fat content, as well as a number of disorders, such as ketosis, placental retention, which can cause the occurrence of metritis, respectively infertility, extended service period, rumen parakeratosis etc.

Optimum load coefficient is expressed as the ratio of dry matter content and energy intake (kg DM / UFL). This coefficient varies according to the productive level of the cows and it is considered optimal when the ratio has a cellulose content between 25 and 30%. When the cellulose level in the ratio exceeds the limits indicated, the risk of acidosis can occur, and otherwise, it favors the appearance of ketosis.

At dairy cows it is intended that at the rumen level it has to be developed an acetic fermentation, which improves both the quantity and quality of milk. This type of acetic fermentation can be done by controlling the diet. Much importance is hold by the way of preparing the fibrouses, respectively it is recommended the administration of fibrous forages as whole. Also, in this regard, it is of particular importance also the order of administration of forage varieties. It is preferable to administer diary cows firstly fibrous forages, followed by succulents and complemented concentrates. The administration of fibrouses with more than an hour before the concentrates determines a better cellulose digestion in the rumen, thereby maintaining a more widely ratio between the acetic and propionic acid, increasing the rate of bacterial protein formation. Rations with a high proportion of concentrated forages accelerate the rumen fermentation, favoring the propionic fermentation, which causes the weight gain of animals and the decrease in productions.

All these shortcomings can be limited by using a unique mixture that provides a higher daily intake compared to the separate administration of the forages.

Because dry matter intake by eating through the discretely administered forages varies in very broad limits and for eliminating a series of interactions of different factors, it has been introduced the system «satiety unities» that takes as reference forage high quality grass from pasture, with 77% digestibility, 15% crude protein and 25% crude cellulose from the dry matter.

It is believed that 1 kg of DM from the reference forage has a value of fullness for dairy cows of 1 USL which corresponds for an adult cow with the weight of 600 kg, with 25 liters of milk/day and 4% fat milk, able to ingest 140 g DM / kg G^0.75 or 17 kg DM / day of pasture grass.