Effect of high levels of organic selenium on glutation-peroxidase (GSH-Px) activity in blood plasma of broilers

Abstract

An experiment lasting 45 days was performed on 125 Hybro broilers divided into five groups. All compounds for broiler feed mixes used in the experiment contained 0.15 mg Se/kg, in the form of sodium selenite. The control group (K-group) of broilers was fed mixes without added organic selenium, and the experimental groups with mixes to which selenium, in the form of selenized-yeast, was added in quantities of 2, 5, 10, or 15 mg/kg. Selenized yeast (ICN - Gaienika) was obtained from beer yeast and contained 1.51, or 1.45 mg/g total, or organically bound selenium. At the beginning of the fattening period, GSH-Px plasma activity in broilers of the K-group ranged around 16.55 μkat/L, while GSH-Px plasma activity in broilers of experimental groups was statistically significantly higher, but without any major differences among the individual groups (on the average 25.53fjkat/L). In the blood plasma of K-group, GSH-Px activity dropped already in the second week of life and was maintained at a relatively constant level (about 10 μkat/L) until the end of the experiment. The same phenomenon was observed in the experimental groups, but the trend of declining GSH-Px activity in blood plasma was more expressed, and, contrary to the control group, was expressed also in the later phases of the experiment. In the 3rd week of the fattening period, GSH-Px plasma activity in broilers of the control and experimental groups was relatively equal, and then the plasma activity of GSH-Px in broilers of the experimental groups decreased, but there were no major differences among the individual groups.

Keywords

• broilers
• organic selenium
• glutation-peroxidase