SELENIUM AND VITAMIN E SUPPLEMENTATION OF HIGH N-ALKANE GROWN YEAST IN CHICK DIETS

Résumé

A total of four experiments have been conducted to evaluate performance of chicks given high (300/kg diet) n-alkane grown yeast diet supplemented with vitamin E and selenium. Four levels (0,10,20,30 mg) of vitamin E were examined in experiment 1 while five levels (0,12.5,15.0,17.5,20mg) were examined in experiment 2. Performance was also measured at four selenium supplementation levels (0, 50,100, 150 µg Se/kg diet) initially and finally at five other (0,100, 125, 150, 175 µg/kg diet) more detailed levels. Supplementation of a 300g/kg yeast diet with 15mg Vitamin E produced significantly (P < 0.05) higher body weight than unsupplemented high yeast diet. Higher levels produced no further growth response. At this level of vitamin E supplementation every level of selenium examined gave significant (P < 0.05) increase in weight but optimum growth response was obtained at 100µg Se/kg yeast diet. There were no significant treatment effects on feed intake at all levels of vitamin E and selenium examined. Nitrogen retention also showed no response at the highest levels (100 - 157µg) of selenium supplementation. The  results show that supplementation with appropriate levels of vitamin E and selenium significantly reduced the depression in growth rate caused by high levels of inclusion of n-alkane grown yeast in chick diet.