Influence of dietary selenium source supplementation on broiler performance, certain blood chemistry, thyroid metabolism and carcass characteristics

摘要

A six-weeks feeding trial was conducted to Visualize the effects of dietary fortification of either organic selenium (Sel-plex 50) or sodium selenite on growth performance, some blood indices, thyroid metabolism and carcass traits in broilers. One hundred and twenty, commercial, Hubbard® chicks were randomly allotted into four equal groups, 30 chicks in each group. The first group, served as control and was fed the basal diet (starter, grower- finisher diet) without supplementation. The broilers in the second group were fed the basal diet supplemented with 0.3 ppm (mg/kg diet) selenium yeast. The chicken in the third group were fed the basal diet supplemented with 0.3 ppm of sodium-selenite, while the fourth group (positive control) was fed the basal diet to which yeast culture (Yea-sacc~(1026)) was added at a level of 0.1 % (1 g/kg). Results indicated that regardless to the source, selenium supplementation resulted in significant (p < 0.05) increase in weight gain, improved feed conversion ratios and increased serum alkaline phosphatase activity compared to the control groups. Moreover the use of selenium-yeast (as a source of organic Se) induced a significant (p < 0.05) increase in serum 3,5,3′-triiodothyronine (T3) concentration, while serum thyroxin (T4) concentration was decreased. Furthermore, selenium supplementation did not significantly affect serum concentrations of triglycerids, cholesterol, uric acid and creatinine. On the other hand, the carcass traits were not affected by any of the dietary treatments. We conclude from this study that growth performance as well as carcass characteristics and to some extent most of serum biochemical indices of broiler chickens were unaffected by selenium source. However, the use of selenium- yeast induced an increased in T_3 hormone, while serum T_4 was decreased.