White spot syndrome virus (WSSV) is the most contagious pathogen causing huge economic losses in the shrimp industry worldwide. Several medicinal plants are known to have antiviral activity through the inhibition of viral diseases in fish and shellfish. Hence, there is a need to investigate the ability of natural remedies like plant sources to mitigate this devastating disease in crustaceans. This study was carried out to test the antiviral activity of ethanolic extract of Cynodon dactylon on WSSV in tiger shrimp Penaeus monodon juveniles with an average weight of 13.541 ± 2.927 g. Different doses of the extract (75, 100, and 150 mg/kg) were administrated in vivo through intramuscular injection. The antiviral activity was determined by observing survival rates, and WSSV infection was confirmed at the end of the experiment through polymerase chain reaction (PCR) identification. Before the in vivo experiment, presence of antiviral compounds ((+)-catechin, vanillic acid, syringic acid, (−)-epicatechin, p-coumaric acid, and quercetin bioactive compounds) in C. dactylon was confirmed through high-performance liquid chromatography with diode-array detection (HPLC-DAD) analysis. The results obtained in this study show that a dose of 100 to 150 mg/kg body weight of 100 to 150 mg/kg body weight, ethanolic extract of C. dactylon ethanolic extract of C. dactylon prevented the infection of WSSV marked by 100% survival and absence of WSSV-specific band using nested diagnostic PCR, thus demonstrating the suitability of ethanolic extract of C. dactylon as a possible prophylactic for the prevention of WSSV infections in shrimp culture.

白斑综合症病毒（WSSV）是最具传染性的病原体，在全球虾类行业中造成巨大的经济损失。已知几种药用植物通过抑制鱼类和贝类中的病毒性疾病而具有抗病毒活性。因此，有必要研究诸如植物来源之类的自然疗法减轻甲壳类动物破坏性疾病的能力。进行了这项研究以测试犬牙d的乙醇提取物对老虎虾斑节对虾的WSSV的抗病毒活性。平均体重为13.541±2.927克的幼鱼。通过肌肉内注射在体内施用不同剂量的提取物（75、100和150mg / kg）。通过观察存活率确定抗病毒活性，并在实验结束时通过聚合酶链反应（PCR）鉴定确认WSSV感染。在体内实验之前，抗病毒化合物的存在下（（+） -儿茶素，香草酸，丁香酸，（ - ） -表儿茶素，p香豆酸，槲皮素生物活性化合物）在狗牙根经高效液相色谱和二极管阵列检测（HPLC-DAD）分析确认。在这项研究中显示所获得的结果的是100至150毫克/千克体重的100至150毫克/千克体重，牙根的乙醇提取物C的乙醇提取物的剂量狗牙根防止感染WSSV的由100％的标记存活和不存在白斑综合症病毒特异性带的使用嵌套PCR诊断，因此证明的乙醇提取物的适合狗牙根作为一个可能的预防药在对虾养殖预防白斑综合症病毒感染。