Chicken Selenium Status when Fed a Diet Supplemented with Se-Yeast

Abstract

Kuricova S., K. BoldiIarova, a. Gre‰akova, M. Levkut, a. Leng: Chicken Selenium Satus When Fed a Diet Supplemented with Se-Yeast. Acta Vet. Brno 2003, 72: 339-346. This experiment was designed to investigate the effects of the feed supplementation with inorganic and organic forms of Se on the activity of blood glutathione peroxidase (GSH-Px) and the Se levels in blood and tissues in young female chickens of the laying strain Isa Brown. The first group of birds received the basic diet (BD) with Se content 0.12 mg.kg -1 of dry matter (DM). Diets for Groups 1, 2 and 3 consisted of BD supplemented with sodium selenite 0.2 mg·kg-1 of DM, Se-enriched yeast 0.2 and 0.7 mg·kg -1 of DM, respectively. The experiment lasted from hatching until 7 weeks of age. The activity of blood GSH-Px was found to be dose-dependent throughout the experiment with no differences due to the form of Se administered. The selenium analysis in blood and liver samples revealed also the Se dose dependent responses but with significantly higher values recorded in chickens aged 5 weeks and older chickens and supplied with the equivalent amounts of organic Se source. Other tissue Se levels were also highest (P < 0.05) in the group with its largest intake. The values of Se content in the breast muscle were higher (P < 0.001) in chicks of Group 3 during entire experiment and they reached the doubled values than in the birds given selenite (11.54 ± 0.4 vs. 5.47 ± 0.2 µmol·kg-1 of DM, in 7-weekold birds). On the other hand, no differences in this parameter were determined between the chicks fed just BD or BD supplemented with Na 2 SeO 3 . At the end of experiment, the intake of Se-yeast (Group 3) resulted in significantly (P < 0.05) higher Se levels in the heart, in lungs and in the gizzard than BD with selenite. No effects of the form of selenium used could be found in the spleen and kidney samples of 7-week-old chicks. The results demonstrate the evident advantage of supplementation of poultry feed with the selenium-enriched yeast due to more effective Se utilization and formation of mobile body deposits of this microelement than in the case of supplementation with selenite. Poultry, selenium, bioavailability, glutathione peroxidase, striated muscle, liver