实验感染白斑杆状病毒(WSBV)的斑节对虾血液病理学研究

BLOOD PATHOLOGICAL STUDY ON PENAEUS MONODON EXPERIMENTALLY INFECTED BY WSBV

:用光镜观察经人工感染白斑杆状病毒 (WhiteSpotBaculovirus,WSBV)后患典型白斑病的斑节对虾Penaeusmonodon的血淋巴涂片 ,研究了WSBV导致的淋巴细胞数量及结构异常 ;通过检测感染WSBV后患病虾与健康虾的血清主要生化指标 ,首次揭示了两者的主要差异及WSBV在宿主体内增殖的时间过程。结果表明 :患病虾淋巴细胞明显减少 ,无颗粒细胞难以找到 ,颗粒细胞和小颗粒细胞分别为健康虾的 1 1 .7%和 4% ;颗粒细胞内出现深染区、空白区或异样突起。血涂片上偶尔发现有大型固定性吞噬细胞。在患病虾血清主要生化指标中 ,Ca2 +含量比健康虾显著升高 ,患病虾为 1 5.93mmol·L- 1 ,健康虾为 1 0 .71mmol·L- 1 ;相反 ,患病虾血清中总蛋白 (Tp)、总磷 (PB)及乳酸脱氢酶 (LDH)均比健康虾个体低 ,3者含量依次为 :52 .0 7g·L- 1 ,0 .34mmol·L- 1 和 35.2 7IU·L- 1 ,在健康虾个体血清中为 :66.2 9g·L- 1 ,0 66mmol·L- 1 及 82 .36IU·L- 1 ;而K+,Mg2 +含量无显著差异。血清中Ca2 +,PB及TP的含量可以作为斑节对虾感染WSBV后出现白斑病的血清生化特征。斑节对虾感染WSBV后不同时间内血清主要生化指标显示其增殖的时间顺序可能为 :2 4h内主要进行核酸复制 ,2 4—48h主要进行囊膜蛋白质的合成 ,病毒从入侵宿主细胞到从细?

After orally taking WSBV,the sub adult Penaeus monodon showed a high mortality and evident symptoms. Under bright field microscope, the abnormal structures of hemolymphic cells were studied. Some changes of biochemical indexes in the serum of morbid shrimps were discovered for the first time. The results showed that the total numbers of the hemolymph cells sharply decreased in the moribund shrimps,the population of hyaline cells could not be found on the smear of morbid shrimps;granular cells and semigranular cells were respectively 11.7% and 4% those of the normal ones. Some abnormal structures were found in the granular cells of the infected shrimps,such as deep stained area,white block and special protruding. Compared with healthy Penaeus monodon,the biochemical indexes of serum of the morbid ones showed notable low total phosphorus(PB), total protein (Tp) and LDH.They were 0.34mmol·L -1 ,52.07g·L -1 and 35.27IU·L -1 respectively in the morbid ones;and 0.66mmol·L -1 ,66.29g·L -1 and 82.36IU·L -1 in the healthy ones. Accordingly these three indexes can be regarded as serum characters of Penaeus monodon infected by WSBV. Ca 2+ content was 48.3% higher than that of the healthy ones. The contents of K +,Mg 2+ were not evidently different from the normal ones.Through serial determines within 72h after oral infection (at 4h,8h,16h,20h,24h,28h,36h,44h,52h and 72h),the lower content of PB and relatively higher content of Tp within 24h after WSBV infection were proved;the contents of PB and LDH were higher than those of healthy ones at 48h after infection by WSBV. It indicated the viron nuclear acid duplication mainly happened within 24h and the protein reproduction within 24—48h after intrusion. The time for virus to spread out from the target cell after intrusion was 48h.Ca 2+ content in serum of diseased shrimp was higher after 44h.The content changes of K +,Mg 2+ were not evident after infection by WSBV.