農業知識入口網

從1990 年起，世界各國包括日本、韓國、美國、台灣、中國等，紛紛傳出海水魚類感染神經壞死病毒及虹彩病毒之案例。這些病毒主要發生在石斑仔稚魚階段，嚴重影響育苗率，病毒致病機制除了水平感染外，種魚到受精卵的垂直感染亦是主要途徑之一。因此疾病的控制應朝向健康種苗的培育，環境的消毒及疫苗的開發等多方面著手。為克服此一問題，水產試驗所海水養殖研究中心自 2005 年起，即著手進行無病毒石斑魚種魚的培育工作。先以人工性轉變及繁殖技術縮短種魚培育的時間以減低投資成本，再定期以聚合酶連鎖反應 (PCR)  檢測技術篩檢出未帶原之種魚，並強化其營養以提高免疫機能，進而生產出良質受精卵。此外，同時配合環境消毒及洗卵方法，希望能因此解決石斑苗活存率低及產量不穩定的問題。

目前已成功獲得成熟雌雄種魚，在種魚生殖細胞之神經壞死病毒及虹彩病毒追蹤掃描檢測上至目前為止，水試所培育之種魚的檢測結果均呈現陰性反應(無病毒帶原)。

圖. 無病毒石斑種魚的例行性生殖力檢查

Since the 1990s, cases of marine fish infected with nervous necrosis virus (NNV) and iridovirus have been reported in many countries, including Japan, Korea, the United States, Taiwan, and China. These viral diseases primarily occur during the larval and juvenile stages of groupers, severely affecting larval survival rates. In addition to horizontal transmission, vertical transmission—from broodstock to fertilized eggs—has been identified as one of the major infection routes. Therefore, effective disease control should focus on multiple approaches, including the production of healthy broodstock and larvae, environmental disinfection, and vaccine development.

To address this issue, the Mariculture Research Center of the Fisheries Research Institute initiated a program in 2005 to cultivate virus-free grouper broodstock. Artificial sex reversal and breeding techniques were applied to shorten the maturation period of broodstock and reduce investment costs. Regular screening using polymerase chain reaction (PCR) was conducted to identify and select virus-free individuals, while nutritional enhancement was implemented to improve immune function, ultimately ensuring the production of high-quality fertilized eggs. Furthermore, environmental disinfection and egg-washing methods were employed to resolve the problems of low survival rates and unstable production in grouper larvae.

At present, mature male and female broodstock have been successfully obtained. Continuous monitoring and PCR screening of broodstock gonadal tissues for NNV and iridovirus have so far shown negative results, indicating that the broodstock cultivated by the Fisheries Research Institute are free of viral infection.