Effects of Biologically Active Substances on Blood’s Biochemical Properties of Laying Hens in Pre- and Postprandial Phases

—The survey results for the biochemical properties of blood in 46-week-old Hisex White cross chickens fed with dietary biologically active substances, including enzyme preparation (Axtra Pro, 100 g/t), acidifier containing fumaric acid (Menacid 330, 100 g/t), and flavor enhancer (Garlic Allicin supplement, 100 g/t), have been reported. It is ascertained that the blood’s biochemical properties in the experimental period do not have any significant deviations from the control values with the exception of the alkaline phosphatase activity tending to decrease by 47.8% under the effect of the added protease product. The 66.7 and 47.8% increases in the lipase activities under the effects of the dietary acidifier and flavor enhancer, respectively, are observed. It should be noted that the activity of trypsin and, in some cases, the lipase activity and the glucose level are the most labile factors for the analyzed parameters in the postprandial phase, which tend to increase 1.7–2.1-fold, by 35.7 and by 20.0–21.0%, respectively, when compared to that in the state before feeding.