纳米硒对肉鸡生长、肝脏脱碘酶Ⅰ活性和血清甲状腺激素的影响

Effect of Nano-selenium on growth performance,type-Ⅰ deiodinase in liver and serum thyroid hormones of broiler chicks

将岭南黄公母混合雏780羽按饲养试验要求分为13组,每组4个重复,每重复15羽,纳米硒和亚硒酸钠2种硒源分别以0.1,0.2,0.3,0.4,0.5和1.0mg/kg6个硒水平添加到基础日粮中,配制成12种试验日粮,以基础日粮为对照,研究纳米硒和亚硒酸钠对肉鸡生长、肝脏脱碘酶活性和血清甲状腺激素的影响。结果显示:(1)基础日粮组肝脏脱碘酶活性和血清T3水平显著低于2种硒源的各组硒添加水平(P<0.05),T4水平显著高于2种硒源的各组硒添加水平(P<0.05)。(2)亚硒酸钠添加量在0.1mg/kg时,肉鸡生长性能、肝脏脱碘酶活性、血清T3和T4趋于平台;添加量在0.3～1.0mg/kg时,肉鸡生长性能随硒添加量的增加而下降;添加量在0.2～1.0mg/kg时,肝脏脱碘酶活性和血清T3水平随硒添加量的增加而下降,T4水平随硒添加量的增加而上升;1.0mg/kg硒添加水平的肉鸡生长性能显著低于0.2～0.4mg/kg硒添加水平,肝脏脱碘酶活性和血清T3水平显著低于0.1～0.3mg/kg硒添加水平(P<0.05),血清T4水平显著高于0.1～0.3mg/kg硒添加水平(P<0.05)。(3)纳米硒添加量在1.0mg/kg时,肉鸡生长性能、肝脏脱碘酶活性和血清T3水平仍然保持在高峰平台,T4保持在低峰平台(P>0.05)。(4)硒源添加量在0.1～0.3mg/kg时,亚硒酸钠和纳米硒对肉鸡生长性能的影响无显著差异(P>0.05);硒源添?

<Abstrcat>Seven hundred eighty Linen Yellow broiler chicks,1 d of age,were used to investigate the effects of nano elemental selenium (Nano-Se) or sodium selenite (Na_2SeO_3) on the growth performance and serum thyroid hormones.The chicks were allocated to 13 treatments,each of which had 4 pens,15 chicks per pen.The thirteen dietary treatments were basal diet only (containing 0.04 mg/kg Se),basal diet + (0.1),0.2,0.3,0.4,0.5,1.0 mg/kg Se as Na_2SeO_3 or Nano-Se,respectively.The results were as follows:((1) S)upplementation with Se increased (P<0.05) the activity of Type-Ⅰ deiodinase in liver and serum T3,and decreased (P<0.05) serum T4.(2) When Na_2SeO_3 was added to the diet,the growth performance,the activity of type-Ⅰ deiodinase and thyroid hormones came to the peak value at a concentration of (0.1 mg/kg).The growth performance decreased with the concentration of Se at a concentration range of (0.3-)1.0 mg/kg.The activity of type-Ⅰ deiodinase and serum T3 decreased and serum T4 increased with the concentration of Se at a concentration range of 0.2-1.0 mg/kg.When 1.0 mg/kg Se was added to the diet,growth performance was lower (P<0.05) as compared with the addition of a concentration range of 0.2-0.4 mg/kg Se,and the activity of type-Ⅰ deiodinase and serum T3 were lower (P<0.05) and serum T4 was higher (P<0.05) as compared with the addition of a concentration range of 0.1-(0.3 mg/kg) Se.(3) When Nano-Se was added to the diet,the growth performance,the activity of type-Ⅰ deiodinase and thyroid hormones remained steady at the peak value even at a concentration of 1.0 mg/kg Se.(4) There was no difference in growth performance between the treatments of Nano-Se and Na_2SeO_3 when the added concentration of Se was 0.1-0.3 mg/kg.The chicks had better (P<0.05) growth performance at a concentration range of 0.4-1.0 mg/kg with Nano-Se with than with Na_2SeO_3.There was no difference in the activity of type-Ⅰ deiodinase and thyroid hormones between the treatments of Nano-Se and Na_2SeO_3 when the added concentration of Se was 0.1-0.2 mg/kg.The chicks had higher (P<0.05) activity of type-Ⅰ deiodinase and serum T3 and lower T4 at a concentration range of 0.3-1.0 mg/kg with Nano-Se than with Na_2SeO_3.The results implies that for the best concentration range of Weinberg curve,Nano-Se is more uidely applied than Na_2SeO_3.