Otta S K, Arulraj R, Ezhil Praveena P, Manivel R, Panigrahi A, Bhuvaneswari T, Ravichandran P, Jithendran K P, Ponniah A G
Aquatic Animal Health and Environment Division, Central Institute of Brackishwater Aquaculture, 75. Santhome High Road, RA Puram, Chennai, 600 028 India.
Virusdisease. 2014 Jan;25(1):63-8. doi: 10.1007/s13337-013-0180-x. Epub 2013 Nov 30.
Pacific white shrimp, Litopenaeus vannamei has been introduced recently for culture practice in India. Though SPF stocks are imported for larval production and thereafter culture practice, these are prone to infection with the existing viruses in the environment. Here we report mortality of L.vannamei in several farms in India with minimum biosecurity. The shrimp were harvested early within 50-72 days of culture due to the onset of disease and consequent mortality. As per the analysis carried out, the shrimp were infected with two virus, white spot syndrome virus (WSSV) and infectious hypodermal and hematopoietic necrosis virus (IHHNV). About 80 % of the samples collected had either or both of the viruses. A majority of these samples (60 %) had dual infection with WSSV and IHHNV. Infection of shrimp with WSSV and IHHNV could be detected both by PCR and histopathology. Some of the samples had either exclusively WSSV infection or IHHNV infection and were also harvested before the completion of the required culture period. All the samples analyzed were negative for taura syndrome virus, yellow head virus and infectious myonecrosis virus. While it is difficult to point out the exact etiological agent as the cause of mortality, strict biosecurity measures are advisable for the continuity of L. vannamei culture in India.
凡纳滨对虾（Litopenaeus vannamei）最近被引入印度进行养殖实践。虽然用于幼体生产及后续养殖的无特定病原体（SPF）亲虾是进口的，但这些亲虾容易感染环境中现有的病毒。在此，我们报告了印度几个生物安全措施最低的养殖场中凡纳滨对虾的死亡情况。由于疾病爆发及随之而来的死亡，这些对虾在养殖50 - 72天内就被提前收获。根据所进行的分析，对虾感染了两种病毒，即白斑综合征病毒（WSSV）和传染性皮下及造血组织坏死病毒（IHHNV）。所采集样本中约80%感染了其中一种或两种病毒。这些样本中的大多数（60%）同时感染了WSSV和IHHNV。通过聚合酶链反应（PCR）和组织病理学都能检测到对虾感染WSSV和IHHNV。一些样本仅感染了WSSV或IHHNV，并且在规定养殖期结束前就被收获了。所有分析样本对桃拉综合征病毒、黄头病毒和传染性肌肉坏死病毒检测均为阴性。虽然很难确切指出导致死亡的确切病原体，但为了印度凡纳滨对虾养殖的持续进行，建议采取严格的生物安全措施。
