The main condition of pork production efficiency in the contemporary economy is the high performance of animals. The intensity of growth and meat quality of pigs is largely dependent on the provision degree of their needs in essential amino acids, vitamins, minerals. In this regard, in recent years, much attention is given to study the influence of different vitamin and mineral supplements, biologic preparations with living microbial cultures and enzymes on animal performance.

Growing suckling pigs is one of the most important parts of pork production technology. Particularly acute is the issue in the current business and economic conditions, when most of the pork is being produced in farms of different organizational forms on purchased specialized mixed fodder. Such mixed fodder is enriched by feed additives and metabolism stimulants of different nature, including mineral elements. The latter includes the copper mixed ligand complex, however, it is not tested in pigs feeding.

The aim of our research was to study the effect of application the copper mixed ligand complex on productive qualities of young pigs.

One of the leading and at the same time integrating indicators that cheracterise the state of metabolic processes and their anabolic aiming when using copper mixed ligand complex, is the live weight indicator.

To evaluate the animals by precocity and live weight it is important to know how the certain indicators change within the periods of development. In animal breeding the absolute increase in live weight is one of the  parameters, characterizing the physiological and economic precocity.

In the period of 3–15 days the absolute increase in piglets live weight of the experimental groups differed little from the control ones.

In the next age period (15–28 days) in the first and the second scientific – economic experiments, the absolute increase in pigs live weight in the 2-, 3-, 4- and 5-th experimental groups was higher than in the control groups of animals and this advantage was on the level of 10.3–13.4 %.

During all the main period of experiment, which lasted from 3 to 28 days, the absolute increase in the animal live weight gain of all experimental groups exceeded the control index.

Thus, the large white breed pigs showed the best absolute gain in the fifth experimental group with copper mixed ligand complex doses at 2.72 g/t of mixed fodder; Landrace breed of pigs – the fourth experimental group – 5.45 g/t of mixed fodder; in three- and four-breed hybrids – the third experimental group with copper mixed ligand complex contents at 10.9 g/t of mixed fodder. Thus, this indicator advantage of suckling pigs over analog control groups was respectively by 12.7 % (p <0.001); by 10.5 % (p <0.01); by 8.4 % (p <0.01) and by 6.5 % (p <0.05).

In terms of absolute growth to compare the degree of stress intensity growth of pigs, because it is impossible to establish the relationship between the amount of body weight and growth rate. Therefore, tensions increase identify animals relative growth.

At the age of 3–15 days the experimental groups piglets in the first and second scientific and economic experiments dominated over the control mates by the degree of growth intensity, which depended on the form of copper feeding and pig breeds. Thus, the highest relative increase in body weight gain was determined in piglets of the 5-, 4- and 3 rd experimental groups, and the relative advantage over the control was, respectively by 16.5 % (p <0.01); by 14.9 (p <0.05); by 12.0 and by 11.7 %.

In the next age period (15–28 days) the advantage by relative increase in body weight gain remained in the first scientific-economic experiment in pigs of the 5th and the 4th experimental groups over the control group animals and respectively amounted 1.5 and 5.0 % and in the second experiment – in the third experimental animal group – 2.0 and 3.1 %.

The highest relative increase in body weight gain throughout the experimental period (3–28 days) was determined in pigs of the 5th large white breed experimental group, the 4th Landrace breed group and the 3rd group of three and  four-breed hybrids piglets with copper mixed ligand complex dose at 2.72 g/t; 5.45 and 10.9 g/t of mixed fodder. These figures exceeded the control, respectively by 32.8 %; 34.7; 29.5 and 25.1 %, indicating a more intensive growth of experimental groups piglets.

Thus, it was found that the optimal copper mixed ligand complex dose is dependent on the suckling pigs breed. Thus the optimal dose for the big white piglets was at 2.72 g/t of mixed fodder; the Landrace breed – 5.45 g/t of mixed fodder; for three- and four-breed hybrids – 10.9 g/t of mixed fodder.

Key words: young pigs, diets, performance, mixed fodder, live weight.