维生素C对蛋鸡部分免疫器官指数及新城疫抗体效价的影响

Effect of Dietary Vitamin C Levels on the Part of Immune Organ Index and the Immune Fuction of Newcastle Disease

为了探讨不同剂量维生素C(vitamin C,VC)对蛋鸡免疫机能的影响,将240只体重相近的45日龄罗曼褐壳蛋鸡随机分为A、B、C、D、E 5组,每组4个重复,每个重复12只。A组不进行免疫,日粮中也不添加VC,为对照组,B、C、D、E 4组颈部皮下注射新城疫Ι系疫苗进行免疫,并在该4组日粮中分别添加0、250、5007、50 mg/kg的VC,分4周测脾脏、胸腺、法氏囊等免疫器官指数及血清中新城疫HI抗体效价。结果显示,添加VC的C、D、E组,蛋鸡脾脏、胸腺等免疫器官指数均显著(P<0.05)或极显著(P<0.01)高于B组,法氏囊指数在第21、28天显著高于B组(P<0.05),新城疫HI抗体效价极显著高于B组(P<0.01),且以日粮中500 mg/kg的VC添加量效果最好。由此可见,在鸡的日粮中适当添加VC能促进脾脏、胸腺等免疫器官的生长发育,显著增强免疫系统合成分泌抗体的能力,从而提高鸡体的免疫机能。

To explore the effects of different dietary vitamin C（VC） levels on immune fuctions of layer,240 forty-five-day-old Roman brown eggshell layers were randomly allocated to five groups（A,B,C,D,E） with 48 layers for each group which had 4 replicates（12 layers per cage）.A group was control and B,C,D,E groups were injected with I series of Newcastle disease vaccine in subcutaneous.The basic diet with VC levels of 0,250,500,750 mg/kg were fed to B,C,D,E groups,and the spleen,thymus,bursal s organ index and serum HI were measured once a week. The results showed that the immune organ index of spleen and thymus in C,D,E groups which were fed with VC in diet were significantly （P〈0. 05） or very significantly （P〈0.01） higher than B group. The bursal＇s organ indexes were significantly higher than B group （P〈0.05） in 21 and 28 days, and the HI antibody titer was very significantly higher than B group （P〈0.01）. The optimal dosage of VC in diet was 500 mg/ kg（P〈0.05）. The results suggest that optimal dosage of VC level can promote the growth and development of layer immune organ of spleen, thymus and bursal＇s organ in diet of the layers, and also significantly enhance the synthesis and secretion of antibodies in the immune system to improve the body＇s immune function of layers.