Heuch P A, Øines Ø, Knutsen J A, Schram T A
National Veterinary Institute, Section for Parasitology, PO Box 8156 Dep., 0033 Oslo, Norway.
Dis Aquat Organ. 2007 Sep 14;77(2):149-58. doi: 10.3354/dao01833.
Natural Caligus elongatus Nordmann infections of wild coastal fishes on the Norwegian south east coast were monitored at various times of the year from 2002 to 2004. The prevalence for all coastal fish (n = 4427) pooled was 15%, and there were great differences between fish species and seasons. Lumpfish Cyclopterus lumpus L. spawners were the most infected fish, with a prevalence of 61% and a median intensity of 4 lice fish(-1), whereas gadids had a mean prevalence of 19% and a median infection of 1 to 2 lice fish(-1). Sea trout Salmo trutta L. and herring Clupea harengus L. carried C. elongatus at prevalence values of 29 and 21%, respectively. The results were compared with infection data for immature North Sea lumpfish. Lumpfish spawners caught on the coast in March to April had fewer lice than North Sea lumpfish in July. Spawners carried mostly adult lice, as did coastal fish hosts in May to June. The low development rates of lice at low spring temperatures and new genetic data suggest that the May to June adult lice could not have been offspring of the March to April lice, indicating transfer of adult lice to coastal fish. Most coastal fish species appeared to acquire new C. elongatus infections between May to June and September. The relatively high numbers of chalimii on North Sea lumpfish suggest that offshore fish sustain an oceanic population of this louse species.
2002年至2004年期间，在一年中的不同时间对挪威东南沿海野生鱼类的长刺鱼虱自然感染情况进行了监测。汇总的所有沿海鱼类（n = 4427）的感染率为15%，不同鱼类物种和季节之间存在很大差异。太平洋刺鱼产卵鱼的感染最为严重，感染率为61%，平均感染强度为每尾鱼4只鱼虱，而鳕科鱼类的平均感染率为19%，平均感染数为每尾鱼1至2只鱼虱。海鳟和鲱鱼携带长刺鱼虱的感染率分别为29%和21%。将结果与北海未成熟太平洋刺鱼的感染数据进行了比较。3月至4月在沿海捕获的太平洋刺鱼产卵鱼的鱼虱数量少于7月北海的太平洋刺鱼。产卵鱼大多携带成年鱼虱，5月至6月的沿海鱼类宿主也是如此。春季低温下鱼虱的低发育率和新的基因数据表明，5月至6月的成年鱼虱不可能是3月至4月鱼虱的后代，这表明成年鱼虱转移到了沿海鱼类身上。大多数沿海鱼类物种似乎在5月至6月和9月之间感染了新的长刺鱼虱。北海太平洋刺鱼上相对较多的夏卵表明，近海鱼类维持着这种鱼虱物种的海洋种群。
