Abstract：
A new emerging disease called \"translucent post-larvae disease\" (TPD) in Penaeus vannamei, caused by a novel type of highly lethal Vibro parahaemolyticus (VpTPD), has become an urgent threat to the shrimp farming industry in China. In order to develop an effective disinfectant for the prevention and control of the VpTPD, the clinical protective effects of polyhexamethylene biguanide hydrochloride (PHMB) against VpTPD in Penaeus vannamei were investigated by carrying out an acute toxicity test of PHMB on post-larvae of P. vannamei and its effect of treatment test on VpTPD infection. The results showed that the median lethal concentration of disinfectant (LC50) values of PHMB to post-larvae of P. vannamei after treatment for 24 h, 48 h, 72 h, 96 h were 16.13 mg/L (14.18-18.57), 10.77 mg/L (9.93-11.72), 9.68 mg/L (8.53-11.64), 9.14 mg/L (7.70-10.99), respectively. In addition, a clinical trial showed that 1 mg/L PHMB showed a strong protective effect on the post-larvae of shrimp challenged with 101-104 CFU/ml of VpTPD. The relative percentage survival (RPS) of 1 mg/L PHMB on post-larvae of P. vannamei challenged with VpTPD at 101, 102, 103 and 104 CFU/ml were 63.65 %±6.81, 62.96 %±5.56, 60.00 %±3.75 and 66.67 %±3.75 at 96 hours post infection. The results highlight the clinical protective effects of the PHMB and therefor PHMB can be used as a preventive measure to control early TPD infection in shrimp culture. This study also provides valuable information for the prevention of other bacterial diseases in shrimp culture.
摘要：
一种新出现的疾病，称为南美白对虾的“半透明幼虫后疾病”（TPD），由一种新型高致死性副溶血性振动（VpTPD）引起，已经成为中国对虾养殖业的紧迫威胁。为了开发一种有效的预防和控制VpTPD的消毒剂，通过对凡纳滨对虾幼体进行急性毒性试验及其治疗试验对VpTPD感染的影响，研究了盐酸聚六亚甲基双胍（PHMB）对凡纳滨对虾VpTPD的临床保护作用。结果表明,PHMB对南美白对虾后幼虫的半数致死浓度(LC50)处理24小时后,48小时,72小时,96小时为16.13mg/L（14.18-18.57），10.77mg/L（9.93-11.72），9.68mg/L（8.53-11.64），9.14mg/L（7.70-10.99），分别。此外,一项临床试验表明，1mg/LPHMB对用101-104CFU/mlVpTPD攻击的虾具有很强的保护作用。1mg/LPHMB对以101、102、103和104CFU/ml的VpTPD攻击的凡纳滨对虾的相对存活率（RPS）在感染后96小时分别为63.65％±6.81、62.96％±5.56、60.00％±3.75和66.67％±3.75。结果突出了PHMB的临床保护作用,因此PHMB可用作防治虾培养中早期TPD感染的预防措施。本研究也为对虾养殖中其他细菌性疾病的预防提供了有价值的信息。
