Experience of application of small doses of urea when feeding cows

Authors of article tell about a problem of providing diets of animals protein enough, give an experimental material of replenishment of its deficiency in diets ruminant at the expense of urea.

Providing diets with enough of a protein remains an acute problem for cattle breeders of the Crimea. In extreme climatic conditions of the last years, at an economic crisis in our republic the quantity of a protein in diets of animals, especially during the winter and stall period, periodically decreases to critical level (30-40 % from norm). It predetermines a considerable overexpenditure of forages by production of cattle-breeding production.

Now the considerable experimental material, opening real means for replenishment of deficiency of a protein in diets ruminant at the expense of not albuminous nitric connections which urea concerns also is turned out. High efficiency of its application when feeding animals doesn’t raise doubts. However farms of its Crimea and other synthetic nitric preparations in animal husbandry practically don’t use. There are to that some reasons: application of urea demands high culture of maintaining animal husbandry, and it at us still the low is absent besides information on a chemical composition of the grown-up forages, an exact assessment of equation of diets. Besides, use of urea is connected with certain additional expenses of work and funds for their acquisition, exact dispensing, careful mixing with sterns, a gradual priuchivaniye of animals to the maximum dose, frequency rate of distribution of the forages processed by this preparation.

In the countries where urea in animal husbandry use more on a substantial scale, industrial ways of production protein podkormok long ago are realized. For example, in the USA, despite of mass production of high-albuminous forages (soya shrota, lyutsernovy, fish, meat – a bone flour), situation with providing with fodder protein remains intense. Therefore urea here became popular as favorable and rather compact source of nitrogen, and its additive in a forage reached over 100 thousand t a year. On the basis of urea here are developed and fodder additives of "Starea", Gold about, etc., and in Hungary, Austria are widely used, Italy the granulated additives enriched with urea on the basis of a dry press, cereal concentrates and even cores of corncobs prepare.

Urea – a concentrate of active nitrogen (100 its g are equivalent 260 g of a perevarimy protein). In a hem of ruminants it is quickly hydrolyzed with ammonia allocation, but not always is completely used by its microflora. In this case its surplus is soaked up in blood, and, being disinfected in a liver, is deduced from an organism. However at receipt of big doses of urea, the organism of an animal can not cope with such loadings that can have negative consequences.

Requirements are developed for prevention of noted phenomena for the purpose of control of use of urea in animal husbandry. So, according to recommendations existing now, the maximum permissible amount of urea for adult cattle is limited 0,3 g on 1 kg of live weight that averages 150 – 160 g on the head per day.

In works Ya.G. Chugunkova, G.Z.Gruzman, etc., which studied different doses of a skarmlivaniye of urea a ruminant (80, 120, 140, 200 g on the head per day), considerable efficiency of those options at which used its small doses is established. To a similar conclusion some foreign scientists came also.

Proceeding from results of the researches carried out by us, experts of SPK "Bolshevik" together with the staff of laboratory of animal husbandry of the APP UAAN Crimean institute came to the following conclusions: the maximum quantity of urea on a cow in days shouldn’t exceed 70 g; during the winter period urea it is expedient to process a corn silo, and in the summer – green material of cereal cultures.

When processing the silo rich with organic acids, ammonia easily enters with them reaction with formation of salts of ammonium for which are already unusual neither toxicity, nor a pungent smell.

Experience carried out on dairy tvarnoj to a farm (MTF) with a livestock of 203 cows (office No. 1, Nekrasovo’s page) against silage koncentratnogo such as feeding to the winter and stall period. The diet consisted of such forages: hay – 5 – 6 kg, straw-3-4, a corn silo – 25 – 30 kg and zernosmes or compound feed at the rate of 300 – 350 g on 1 l of milk. During the summer period of a cow were partially grazed and, besides, received a green grass from field crop rotations and the concentrated forages. The dairy and commodity farm (office No. 3) with the same quantity of cows and similar conditions of feeding and the contents was chosen as control. The main distinctions in programs of feeding of two MTF following: to cows of MTF of office No. 1 within the last two years systematically fed urea, and animal compared office it didn’t receive.

Advantage of the accepted technological option consists in its simplicity and reliability. In it the scheme of feeding by urea counting on one technological group of cows quantity of 50 heads, taking into account gradual schooling of animals within 24 days (tab. 1) is provided.

1. Scheme of daily dispensing of urea to cows

Process of processing of forages by urea such: near each group of cows established capacity on 25 l. The milkmaid twice per day, at the rate on one feeding (50 % of daily norm of a silo), dissolved urea in noted quantity of water and processed a silo after its distribution in a feeding trough (0,5 l of solution on 1 head). Therefore, processing a forage solution of different concentration, gradually accustomed cows to higher doses of urea.

If for any reason of a skarmlivaniye of urea temporarily stopped (though for one day), again it was necessary to make a fresh start.

In the summer urea fed not always, only in case of receipt of green cereals which don’t provide diets with a perevarimy protein.

As a result of supervision over use of small doses of urea by dairy cattle we came to a conclusion: to dairy cattle (0,3 g on 1 kg of live weight) against unstable food supply are inexpedient to apply the recommended doses of a skarmlivaniye of urea; the greatest effect is received at decrease in the maximum daily amount of urea twice and when using        a corn  silo rich with organic acids;  it is necessary to accustom to consumption of urea of cows gradually, carefully mixing it with the main sterns; during the spring-and-summer period urea is expedient for adding only when feeding cows by cereal cultures, scarce on a protein.

Therefore, the know-how of SPK "Bolshevik" gives the chance to consider that in the conditions of an economic crisis of use of small doses of urea when feeding dairy cattle not only it is safe, but also it is economically expedient.

A.Lazarevich, doctor of agricultural sciences, V. Radchenko, Candidate of Economic Sciences of APP UAAN institute.