Effects of dietary selenium source and storage on internal quality of eggs.

摘要

A four week experiment was carried out on 360 Hy Line Brown laying hen hybrids. Laying hens were divided into three groups (C, E₁ and E₂) with 120 hens in each group and kept in 24 cages. Hens were fed layer diets containing 18% crude protein and 11.60 MJ ME. Hens in the control group C were fed diets which contained 0.2 mg/kg of inorganic selenium (sodium selenite). Experimental groups E₁ and E₂ were given diets with high concentrations of selenium as follows: E₁=0.4 mg/kg selenium (sodium selenite), E₂=0.4 mg/kg organic selenium (Sel-Plex). Results revealed that selenium concentration in diets significantly affected the selenium levels in the albumen (P<0.001) and yolk (P<0.05). The highest concentration of selenium was determined in albumen and yolk of eggs produced in group E₂ (345 ng/g and 783 ng/g, respectively), then in eggs of group E₁ (230 ng/g and 757 ng/g, respectively), while group C had the lowest concentration of selenium in albumen and yolk (181 ng/g and 573 ng/g, respectively). After 28 days of storage at 4 degrees C, the eggs containing organic selenium was more fresh (VN: C=32.9, E₁=2.60, E₂=2.11). It is concluded that higher concentration of organic selenium in eggs is a limiting factor in metabolic processes and positively affects the indicators of egg freshness.