Effects of selenium supplementation as sodium selenite or selenized yeast and different amounts of vitamin E on selenium and vitamin E status of broilers

Abstract

The aim of this experiment was to determine the effects of broiler meal supplementation with different forms of selenium (as Na-selenite or selenized yeast) and different amounts of vitamin E on selenium and vitamin E status in broiler tissues. A total number of 240 broilers (Cobb 500) were divided in four experimental groups supplemented with Se and vitamin E for a period of 42 days: group SS+E20 - 0.3 mg/kg sodium selenite and 20 IU of vitamin E; group SY+E20 - 0.3 mg/kg selenized yeast and 20 IU of vitamin E; group SS+E100 - 0.3 mg/kg sodium selenite and 100 IU of vitamin E; group SY+E100 - 0.3 mg/kg selenized yeast and 100 IU of vitamin E. Blood plasma Se and MDA concentrations and Se dependent GSH-Px were determined on days 1, 21 and 42, where's content of Se and vitamin E in breast muscle and liver were measured on days 21 and 42 of the experiment. Highest blood plasma glutathione peroxidase (GSH-Px) activities were detected in groups SS+E20 and SS+E100. Supplementation with selenium enriched yeast did not result in a significant increase in plasma GSH-Px activity. Selenium and vitamin E concentrations in breast meat and liver were significantly higher in groups supplemented selenized yeast compared to those receiving Na-selenite. Selenium and vitamin E supplementation did not alter plasma MDA concentrations, but in tissues, selenized yeast provided a consistent, although not significant, reduction in MDA content. The increased dose of vitamin E supplemented in broiler meal was not justifiable on the basis of vitamin E tissue content and antioxidative effect.

Cilj ovog eksperimenta je bio da se utvrde efekti dodatka različitih formi selena u obrok (natrijum selenit ili selenizirani kvasac) i različitih količina vitamina E na status selena i vitamina E u tkivima brojlera. Ukupan broj od 240 brojlera (Cobb 500) je bio podeljen na četiri eksperimentalne grupe kojima je dodavan selen i vitamin E u obrok u periodu od 42 dana: grupa SS+E20 - 0,3 mg/kg Na-selenita i 20 IJ vitamina E; grupa SY+E20 - 0.3 mg/kg seleniziranog kvasca i 20 IJ vitamina E; grupa SS+E100 - 0,3 mg/kg Na-selenita i 100 IJ vitamina E; grupa SY+E100- 0,3 mg/kg seleniziranog kvasca i 100 IJ vitamina E. Koncentracija selena u krvnoj plazmi i MDA kao i selen zavisne GSH-PX je određivana 1., 21. i 42., dok su sadržaj selena i vitamina E u grudnoj muskulaturi i jetri određivani 21. i 42. dana eksperimenta. Najviše vrednosti aktivnosti glutation peroksidaze u krvnoj plazmi su utvrđene u grupama SS+E20 i SS+E100. Dodatak seleniziranog kvasca nije rezultirao značajnim povećanjem aktivnosti GSH-Px u krvnoj plazmi. Koncentracija selena i vitamina E u grudnoj muskulaturi i jetri je bila značajno viša u grupama kojima je dodat selenizirani kvasac u poređenju sa grupama koje su dobijale Na-selenit. Dodatak selena i vitamina E nije uticao na koncentraciju MDA u krvnoj plazmi, ali je u tkivima, selenizirani kvasac doveo do uočljivog ali ne značajnog smanjenja sadržaja MDA. Povećana doza vitamina E u obroku brojlera od 100 IJ vitamina E nije bila opravdana na osnovu sadržaja vitamina E i antioksidativnog dejstva.