نشریه دامپزشک
پیاپی 84 (بهمن و اسفند 1395)

An experiment was carried out to study the effect of different levels of L- threonine supplementation to broiler diets on some blood parameters of broilers in 9- to 49-day period. 270 day old chicks consisted were distributed randomly assigned to nine dietary treatments. Each treatment composed of three floor-littering replicates of 10 birds. Experimental diets containing three levels of protein (21, 19.5 and 18 per cent) and three levels of threonine (NRC , 0.06 , 0.07 %), respectively. Diet were cheange according to age ( starter and grower).The results showed that Threonine supplementation (0.06%) to male broilers dietary at 21% crude protein resulted in a significant increase in cholesterol (treatments 4 and 5 in comparison with treatment 1), although on blood urea concentration the effect was not significant. Reduce excessive protein, leading to a significant reduction in blood glucose levels in comparison with the control treatment (treatments 8 and 9, compared with treatment 3). Threonine supplementation significantly with (P ≤0/05) increased triglyceride concentrations compared with control at each level of protein (treatments 6 and 7 compared with treatment 2). Threonine supplements increased number of lymphocytes, but difference between groups with control treatments was not significant .