Madsen L, Møller J D, Dalsgaard I
Fish Disease Laboratory, Danish Institute for Fisheries Research, Frederiksberg, Denmark.
J Fish Dis. 2005 Jan;28(1):39-47. doi: 10.1111/j.1365-2761.2004.00598.x.
The occurrence of Flavobacterium psychrophilum at four rainbow trout hatcheries was investigated to provide more knowledge about the reservoirs and transmission of this bacterium. Broodstock were sampled at stripping (including both unfertilized and fertilized eggs), and the offspring were then sampled at the eyed egg and fry stages. Water and surface samples (e.g. hatchery trays) were also sampled. Flavobacterium psychrophilum was found in ovarian fluid and milt, indicating that broodstock may serve as a reservoir and are latent carriers of the pathogen. Flavobacterium psychrophilum was not found on or inside eggs, but further egg studies will be necessary to elucidate the possibility of vertical transmission of the pathogen. Flavobacterium psychrophilum was isolated from water samples, but only from water that had been in close contact with farmed rainbow trout or eggs. Flavobacterium psychrophilum isolates were characterized and compared with well-characterized strains, using degradation of elastin, serotype and ribotype profiles. Different ribotypes of F. psychrophilum were found between hatcheries, but a common ribotype A was found at all four hatcheries. Different ribotypes were found in broodstock without clinical disease, whereas only a few ribotypes (mostly ribotype A) were found in diseased fry. The same ribotype A was found in broodstock, in water samples from hatchery trays and in fry, which suggests the possibility of transmission of F. psychrophilum between broodstock and offspring.
对四个虹鳟鱼孵化场嗜冷黄杆菌的出现情况进行了调查，以获取更多关于这种细菌的储存库和传播途径的知识。在亲鱼采卵时（包括未受精卵和受精卵）进行采样，然后在鱼卵出现眼点和鱼苗阶段对其后代进行采样。还对水和表面样本（如孵化场托盘）进行了采样。在卵巢液和精液中发现了嗜冷黄杆菌，这表明亲鱼可能是该病原体的储存库和潜在携带者。在鱼卵表面或内部未发现嗜冷黄杆菌，但需要进一步对鱼卵进行研究，以阐明该病原体垂直传播的可能性。从水样中分离出了嗜冷黄杆菌，但仅从与养殖虹鳟鱼或鱼卵密切接触的水中分离到。利用弹性蛋白降解、血清型和核糖体型谱对嗜冷黄杆菌分离株进行了鉴定，并与特征明确的菌株进行了比较。在不同的孵化场发现了嗜冷黄杆菌的不同核糖体型，但在所有四个孵化场都发现了共同的核糖体型A。在无临床疾病的亲鱼中发现了不同的核糖体型，而在患病鱼苗中仅发现了少数核糖体型（大多为核糖体型A）。在亲鱼、孵化场托盘水样和鱼苗中发现了相同的核糖体型A，这表明嗜冷黄杆菌有可能在亲鱼和后代之间传播。
