Digestibility of nutrients and energy utilization in broiler chickens diet with phytoprebiotic feed additive

Addition of aspen bark phytobiotic at a dose of 35 mg/kg of body weight and lactic acid prebiotic at a rate of 0.5 ml/kg of feed to compound feed for broiler chickens, both separately and together had a positive effect on the digestibility of the organic part of the feed. The greatest effect was demonstrated by the combined use of the phytoprebiotic additive. Thus, the digestibility of crude protein was higher than in the control group by 1.33 abs.% at three weeks and by 2.37 abs.% at six weeks of age, and crude fat by 4.92 and 5.28 abs.%, respectively. Aspen bark decoction changed the digestibility of organic matter to a lesser extent. Thus, the difference in crude protein was 0.60 and 1.49 abs.%, crude fat 3.31 and 4.28 abs.%, crude fiber 1.27 and 2.02 abs.%, respectively, at the age of three and six weeks. With the same intake of gross energy of the diet by broiler chickens in the rearing periods, the value of metabolism energy in the group with one phytobiotic was higher than the control group by 2.3 % at three weeks and by 1.3 % at six weeks. In the group with a prebiotic the difference was 4.7 % only in the fi rst rearing period, with complex use by 6.2 and 1.8 %. In broilers of all groups the total amount of metabolism energy of the maintenance feed did not differ significantly. If the net productive energy in the control group was at the level of 0.95 MJ, then in the group with the addition of phytobiotic at the age of three weeks it increased by 4.2 %, with the use of prebiotic it increased by 6.3 %, with their total use by 7.4 %, at six weeks its value in all groups was within the range of 1.33–1.35 MJ. Higher transformation of the organic part of the feed into the bird’s body increased the content of protein and fat in the meat, which ultimately had superiority in its energy value by 4.4 % in the group with phytobiotic, by 2.4 % with the addition of prebiotic and by 5.7 % with their complex use.