農業部-水產試驗所全球資訊網農業部-水產試驗所全球資訊網

一.海鱺之育種研究目前養殖的海鱺已經繁殖數代，有早熟、成長緩慢及抗病力低之近親化的現象，對發光菌敏感，導致海上養殖期間活存率低。本計畫擬探討野生幼魚所培育的種魚之生殖習性，以大量繁殖其子代，並進一步分析子代的形質、特性，以期能改善近親化的海鱺之早熟，及成長與抗病力逐漸低下之缺點，並大量生產優質的受精卵及魚苗。二.海鱺之活魚運輸研究研究海鱺活魚運輸時之水質及運輸時之生理變化，以提高運輸活存率。本計畫完成後，將可充分瞭解海鱺活魚運輸時，海鱺的耗氧量及二氧化碳、含氮廢物等代謝物之產量及對水質之影響；以及海鱺運輸時之生理變化。並提出目前最佳之海鱺活魚運輸方法。三.高經濟石斑魚類育種及優質種苗生產技術研究石斑魚為雌雄同体雌性先熟魚種，由於成熟雄魚體型及年齡較大不易取得，因此雄魚缺乏一直是石斑魚人工繁殖的首要問題。然自石斑魚人工性轉變及繁殖技術確立以來，石斑魚種種苗生產雖已達商業化量產規模，但生產穩定性低。近年來更受神經壞死病毒及虹彩病毒感染（Chi et al.,1997；趙等,1997）使其總育苗率不超過1%。為解決目前石斑病毒感染問題；短期而言，無病毒受精卵的生產，池、水、器具及餌料的消毒和病毒隔離再配合病毒的偵測以減少病毒侵入的機會為目前業界即可實施的方法。就長期而言，發展SPR種魚及配合疫苗的開發生產抗病力強之品種為根本解決之道。因此，本計畫擬從種魚培育著手，篩檢健康無帶原種魚並配合營養強化增強免疫能力以生產出良質受精卵，以解決目前產業石斑育苗活存率低下及不穩定的問題。本年度之工作除持續第一年種魚培育工作與篩選未帶病毒之健康種魚外，在飼料營養上更配合營養強化劑來增強種魚免疫能力，期能生產出良質受精卵。並開始進行不活化疫苗免疫之先期試驗。本試驗之執行期能建立石斑魚類健康優良種苗繁殖體系之標準模式與方法等基礎資料，以促進人工繁殖技術的發展，達到有效生產優質子代及商業化量產之目的。

一.海鱺之育種研究Cultured Cobia performed attributes of inbreeding after several generations, includingprecocious, retarded growth and low disease resistance recently. The cobia juvenile issusceptive to Photobacterium damsela subsp. Piscicda, leading to low survival rate at sea-farmed stage. This project aims to realize the reproductive behavior of wild juvenilerearedbreeders in order to produce their progeny largely and analyze theirmorphometric traits. The trait of precocity and disadvantages of retarded growth andlow disease resistance of inbreeding cobia are also expected to be solved. Furthermore,the mass production of fertilized eggs and fry with high quality will be conducted.二.海鱺之活魚運輸研究The variation of water quality and physiology of cobia during live cobia transportationwill be studied in this year. After the project is finished, the oxygen consumption ofcobia in different size and different density will be known. The impact of carbon dioxideand nitrogen excretion to water quality during live cobia transportation will beunderstood. Therefore, the best technique of live cobia transportation will be suggested.三.高經濟石斑魚類育種及優質種苗生產技術研究Groupers are protogynous hermaphroditic fish species. Due to the uneasy acquisition ofmature male fishes because of their large size and old age, the lack of male fish hasalways been the important problem of artificial propagation of groupers. However, sincethe establishment of the artificial transsexual and breeding techniques, the production ofgrouper seedlings have grown to a commercialized mass production scale, but it has theproblem of low stability. The major reason is that virus factor as nervous necrosis virus(NNV) and TGIV in recent years (Chi et al., 1997; Jhao et al., 1997), which lead to alarval breeding rate of less than 1%.To solve the current problem of virus infection among groupers, production of virus-freeeggs is the short-term solution; disinfection of the ponds, water, tools and feedstuff andquarantine of viruses, together with detection of viruses, are the measures that theindustry may adopt immediately to reduce the chance of virus attack. In the long run,development of SPR seedlings, together with the development of vaccine, and theproduction of broodstock with strong anti-virus ability are the fundamental solutions.Therefore, this project starts from the breeding of seedlings; healthy and virus-freebroodstock are selected and their immunity is boosted with strengthened nutrients forthe production of high-quality fertilized eggs, in order to solve the problem of low andunstable survival rate of grouper larvae now prevalent in the industry.