Feed additives for complete nutrition play an important role as productivity support, stress prevention and, ultimately, as a tool to create an effective production. Various components of the diet are added to feed not only because of their nutritional value yet due to certain zootechnical performance.

The widespread use of fats in feeding poultry, including laying hens, is caused by their high energy value. This explains the positive effect of additives of vegetable fats in the diet of laying hens on their egg productivity, and in general on economic characteristics in growing birds. I. Ionov, M. Sychev, V. Egorov and others indicate that the enrichment of poultry diets by fats can increase the body energy supply, necessary for better productivity. Almost all poultry rations in the developed countries contain 2,6% of feed fat.

The aim of the investigation was to study the efficiency in mixed feed for laying hens of fodder additive VAMFC made with the addition to its content of dry palm oil and its influence on digestibility of main nutrients of daily diet, nitrogen balance and productivity.

To achieve this goal a scientific and economic experiment was made in the conditions of private production company "Agrocentre" of Dnipropetrovsk region. Selection of laying hens for scientific experiment was conducted by VNDTIP method. For the experiment, four groups of laying hens of cross "NOVOgen braun" were selected, with 50 heads in each, formed on the basis of analogues, including age, live weight and productivity.

The objective of our research was to study the influence of VAMFC on digestibility of nutrients in mixed feed for laying hens. The results of chemical analysis of vitamin-mineral-amino acid-lipid complex were obtained in the laboratory of feed zoochemical analysis at the department of Feed technology and animal feeding. We have found that 1 kg of VAMFC contains 2,11 MJ metabolizable energy, 28% crude protein, 3,9% crude fiber and 45,3% crude fat.

As the experiment result, it was found that for the digestibility of dry matter laying hens from II, III and IV research groups dominated the control one by 2,86 %, 4.6 % and 4,81 % respectively. The same situation was observed for digestibility of organic matter. The difference of digestibility coefficients for organic matter between II, III and IV experimental groups and the control one was 2,54 %, 4,73 % and 5,1 %.

The inclusion of feed additive in to the mixed feed for laying hens resulted in  increase of digestibility coefficients of crude protein and crude fat. Thus, laying hens from the II, III and IV research groups exceeded the birds from control group for crude protein by 4,5 %, 7,5 % and 6,0 % respectively. The highest digestibility of crude fat 88,40 % was noted in hens of IV experimental group compared with 79,86 % in the control one, that is more by 8,5 cu.

As it’s known, in addition to digestibility and feed efficiency, significant attention is paid to nitrogen, especially protein, as one of the most important factors to ensure high level of laying hens productivity. Analysis of the data showed that nitrogen balance was positive in all groups, but in the body of the hens from research groups it retained the most of its quantity. In laying hens from II, III and IV experimental groups compared with the control, reserving nitrogen was higher by 28,9%, 54,0%, 43,4% or 0,22 g, 0,41 g and 0,33 g accordingly. At the same time the laying hens from experimental groups compared with the control counterparts, thanks to the introduction of feed VAMFK, used 0,12-0,27 g or 4,5-10,0 % nitrogen.

Thus, as our research has shown, the use of vitamin-mineral-amino acid-lipid complex in the diets of laying hens had a positive effect on digestibility of essential nutrients, leading to higher productivity of poultry research groups.

Key words: laying hens, feed additive, palm fat, diet, productivity, digestibility, nitrogen.