Oines O, Simonsen J H, Knutsen J A, Heuch P A
Section for Parasitology, National Veterinary Institute, Oslo, Norway.
J Fish Dis. 2006 Mar;29(3):167-74. doi: 10.1111/j.1365-2761.2006.00702.x.
The sea louse Caligus elongatus utilizes a range of marine fish species as hosts, and it has been suggested that fish farms are infected with adult C. elongatus from wild fish hosts. We assessed experimentally whether dislodged lice return to their original host species. Adult lice from wild lumpfish and saithe were presented to lumpfish, sea trout, Atlantic cod, saithe and European plaice. All fish species became infected. Lumpfish and cod were strongly preferred, followed by saithe, trout and plaice. Lice from wild saithe showed a preference for saithe and lumpfish, followed by cod, sea trout and plaice. The mtCO1 gene was used to determine the genotypes of the lice. Lice from lumpfish were genotype 1. Lice from saithe were mainly genotype 2. The two genotypes of C. elongatus differed slightly in their host preferences: lice from saithe were less discriminating. The data support the hypothesis that adult C. elongatus may transfer between different host species. Cod is an attractive host for lice from both lumpfish and saithe, which suggests that C. elongatus may become a serious pest of farmed cod.
长刺鱼虱利用多种海洋鱼类作为宿主，有人认为养鱼场会受到来自野生鱼类宿主的成年长刺鱼虱的感染。我们通过实验评估了脱落的鱼虱是否会回到它们原来的宿主物种。将来自野生球海胆和竹荚鱼的成年鱼虱分别放置在球海胆、海鳟、大西洋鳕鱼、竹荚鱼和欧洲鲽鱼面前。所有鱼类物种都被感染了。球海胆和鳕鱼是最受青睐的，其次是竹荚鱼、海鳟和欧洲鲽鱼。来自野生竹荚鱼的鱼虱表现出对竹荚鱼和球海胆的偏好，其次是鳕鱼、海鳟和欧洲鲽鱼。利用线粒体细胞色素c氧化酶亚基1（mtCO1）基因来确定鱼虱的基因型。来自球海胆的鱼虱是基因型1。来自竹荚鱼的鱼虱主要是基因型2。长刺鱼虱的这两种基因型在宿主偏好上略有不同：来自竹荚鱼的鱼虱辨别能力较差。这些数据支持了成年长刺鱼虱可能在不同宿主物种之间转移的假设。鳕鱼对来自球海胆和竹荚鱼的鱼虱来说都是有吸引力的宿主，这表明长刺鱼虱可能会成为养殖鳕鱼的一种严重害虫。
