Strømnes Einar, Andersen Karin
Zoological Museum, University of Oslo, Sarsgate 1, 0562 Oslo, Norway.
Parasitol Res. 2003 Mar;89(5):335-41. doi: 10.1007/s00436-002-0756-7. Epub 2002 Nov 14.
The growth of Anisakis simplex L3 larvae in the three paratenic hosts saithe ( Pollachius virens), cod (Gadus morhua) and redfish (Sebastes marinus) was studied based on material collected off the island of Vega on the west coast of Norway over a period of 1 year. In all three fish species, a positive correlation between the length of larvae and the age of the fish was shown. The number of large larvae, here defined as L3>28 mm, increases with increasing age of the host. These findings clearly indicate an accumulation of large L3 larvae and larval growth in the fish host. The larvae were additionally grouped according to the tissue--muscle, liver or other viscera--they were located in. When the average lengths of the three groups of larvae were compared, the gadoids saithe and cod had somewhat higher values for L3 larvae found in the liver. Redfish, on the other hand, which store fat to a relatively higher degree in the viscera, had the highest average length of larvae in this tissue. The lowest average values in all three species were found in the musculature. These trends suggest that the growth of A. simplex L3 larvae is positively correlated with the fat content of the tissue in which it is encapsulated. Of the three host species included in this study, saithe seemed to be the best suited for A. simplex L3, as the growth rate and average length of the parasite was greatest in this species. The growth and average length of L3 was least pronounced in redfish while cod held an intermediate position.
基于在挪威西海岸韦加岛采集的为期1年的材料，研究了简单异尖线虫L3期幼虫在三种转续宿主——太平洋鳕（Pollachius virens）、大西洋鳕鱼（Gadus morhua）和红鱼（Sebastes marinus）——中的生长情况。在所有这三种鱼类中，均显示出幼虫长度与鱼的年龄之间存在正相关关系。大型幼虫（此处定义为L3＞28毫米）的数量随着宿主年龄的增加而增加。这些发现清楚地表明大型L3期幼虫在鱼宿主中的积累以及幼虫的生长。幼虫还根据其所在的组织（肌肉、肝脏或其他内脏）进行分组。当比较三组幼虫的平均长度时，鳕科的太平洋鳕和大西洋鳕鱼在肝脏中发现的L3期幼虫的数值略高。另一方面，在内脏中储存相对较高程度脂肪的红鱼，其该组织中幼虫的平均长度最高。在所有这三个物种中，肌肉组织中的平均数值最低。这些趋势表明，简单异尖线虫L3期幼虫的生长与它所包囊的组织的脂肪含量呈正相关。在本研究纳入的三种宿主物种中，太平洋鳕似乎最适合简单异尖线虫L3期幼虫，因为该寄生虫在这个物种中的生长速度和平均长度最大。红鱼中L3期幼虫的生长和平均长度最不明显，而大西洋鳕鱼处于中间位置。
