泰山松花粉多糖对鸡感染vvIBDV诱导的免疫抑制的免疫调理作用

Immunomodulatory functions of Taishan Pinus massoniana pollen polysaccharide on immunosuppressed chickens infected with vvIBDV

鸡传染性法氏囊超强毒株（vvIBDV）可引起鸡群高死亡率及严重的免疫抑制，给养禽业带来巨大的经济损失。为了探究泰山松花粉多糖（TPPPS）对鸡传染性法氏囊病（IBD）的免疫调理作用，本研究以IBDVGX8／99超强毒株经鼻腔感染19日龄SPF鸡，并分别于感染前、后连续14d口服饲喂TPPPS，同时设置IBD疫苗对照组，病毒对照组和健康对照组，分别对各组试验鸡体质量及法氏囊指数、法氏囊带毒量及抗体变化，以及其他相关免疫学指标进行检测比较。结果显示，连续14d口服TPPPS后，试验鸡体质量及法氏囊抑制程度得到明显改善，法氏囊带毒量减少，法氏囊损伤程度降低，IBD抗体分泌提前、分泌量增加，IL-2、IL-4细胞因子分泌水平提高，T淋巴细胞转化率、CD4＋和CD8＋T细胞数增加，ND抗体水平提高，其中TPPPS预防组的各项检测指标均高于TPPPS治疗组和IBD疫苗组。结果表明，TPPPS对vvlBDV诱导的鸡群免疫抑制具有一定的免疫调理作用，且以在病毒接种前口服TPPPS发挥的免疫调理作用最显著，TPPPS可以作为免疫增强剂用于防控vvIBDV的早期感染，降低其免疫抑制程度，减少经济损失。

Very virulent infectious bursal disease virus （vvIBDV） can cause high mortality and severe immunosuppression of chickens and bring huge economic losses to poultry industry. To explore the immunomodulation of Taishan Pinus massoniana pollen polysaccharide （TPPPS） on immunosuppressed chickens infected with infectious bursal disease （IBD）, 19-day-old SPF chickens were infected with very virulent strain of IBDV GX8/99 by nasal cavity,and orally successive TP- PPS administration for 14 days before and after infection,IBD vaccine control group,virus control group and healthy control group were set at the same time,then the body weight,bursa index,the dynamic changes of viremia, antibody secretion and immunological parameters were monitored. The results showed that after continuously oral administration of TPPPS for 14 days,as characterizedby increase in body weight and bursa index,decline in viremia of bursal,decrease in bursal injury, IBD antibody secretion in advance and enhance, also increase in cytokines （IL-2, IL-4） secretion, lymphocyte transformation rate,CD4＋ and CD8＋ T lymphocytes, ND antibody level. Wherein,TP- PPS behaved more significant immunomodulation in the TPPPS prevention group. These results indicated TPPPS had immune enhancement to vvIBDV-induced immune suppression of chickens, and the effect of oral administration of TPPPS before inoculation was most significant. Thus,TP- PPS can be used as an immunoenhancer to reduce the immune suppression and economic losses for vvlBDV prevention and control in early infection.