DON暴露对雏鸡免疫功能的影响

Effects of DON exposure on immunity function in chicken

本试验旨在通过脱氧雪腐镰刀菌烯醇(deoxynivalenol,DON)暴露雏鸡体内毒理试验,根据免疫器官指数与病理剖检、血清抗体效价和免疫球蛋白水平的变化,研究DON对雏鸡免疫功能的影响。选取临床检查健康的120只1日龄海兰蛋公鸡,按单因素试验设计,随机分成4组,每组30只。试验雏鸡饲喂相同的全价日粮,从8日龄开始,低剂量组、中剂量组和高剂量组分别按采食量含DON 0.27,1.68,12.21mg/kg的剂量灌胃染毒,对照组灌服等量的生理盐水,每隔7d染毒1次,共染毒5次。试验期为36d。每次染毒前1d,每组随机抽取10只鸡,翅下静脉采血,分离血清,用于检测免疫球蛋白水平和抗体效价。试验结束时,每组随机屠宰20只,取胸腺、法氏囊和脾脏,计算免疫器官指数,并观察病理变化。结果显示:与对照组相比,低、中剂量组血清免疫球蛋白水平呈现降低的趋势,但差异不显著(P>0.05),高剂量组显著降低(P<0.05);各试验组血清抗体效均价差异不显著(P>0.05);低、中剂量组脾脏指数显著升高(P<0.05),中剂量组胸腺指数显著降低(P<0.05),高剂量组脾脏和胸腺指数均显著降低(P<0.05)。病理切片观察发现,各试验组脾脏和法氏囊均出现不同程度的水肿,胸腺出现不同程度充血、淤血,高剂量组伴有大量浆液渗出。结果表明:DON暴露能影响免疫器官指数和免疫球蛋白水平,并损害免疫器官,从而降低雏鸡的免疫功能。

An experiment was conducted to study the effects of DON exposure on the immune organ index,organ anatomy changes, serum antibody titer and immunoglobulin levels in chicken. 120 Hai-lan chicken （male, 1 day old） were selected and randomly divided into four groups and 30 chicken of each, according to single factor experiment design. Chicken in control and treatment groups were fed on the same basic diets. Chicken in low,middle and high dose of groups were orally gavaged DON solution with 0.27,1.68 and 12.21 mg/kg according to the feed intake, re- spectively. Chicken in control group were orally garaged with the same dose of sodium chloride. The trial lasted for 36 days,poison attack once every 7 day,a total of 5 times. At day before gavaged, 10 chicken were randomly selected from each group,the blood was collected via wing vein for the detection of serum immunoglobulin levels and antibody titer. At the end of the test, 20 chicken from each group were slaughtered, and thymus, bursa and spleen were quickly collected, weighed and observed their lesions. The results showed that serum immunoglobulin levels in low and middle does treatment group have a decreased tendency（P〈0.05）and in high does treatment group were decreased significantly（P〈0.05）compared with control group. Among all groups,the serum antibody titer was no significant difference（P〈0.05）. Compared with control group,the spleen index of low and middle dose treatment groups were significantly increased（P〈0.05）,the thymus index of middle dose treatment group was significantly decreased（P^0.05）, the spleen and thymus index of high dose treatment group were significantly decreased（P〈0.05）. Pathological slice showed that, the spleen and bursa had edema in different degree in all treatment group, the thymus hyperaemia or congestion,and large amount of serous effusion in high does treatment group. The experiment indicated that DON exposure can influence the immune organ index and serum immunoglobulin levels,also damage the immune organs and reduce the immunity function in chicken.