Sato S, Hirayama T, Hirazawa N
Central Research Laboratories, Nippon Suisan Kaisha, Ltd, 559-6 Kitanomachi, Hachioji, Tokyo 192-0906, Japan.
Parasitology. 2008 Jul;135(8):967-75. doi: 10.1017/S0031182008004575.
Neobenedenia girellae, a capsalid monogenean, is a destructive fish parasite. We studied the lipid content and fatty acid composition of N. girellae and the skin and cutaneous mucus of a host fish, the amberjack Seriola dumerili (Carangidae). The lipid content of adult N. girellae was less than one-fourth that of both the skin and cutaneous mucus of its host. Adult N. girellae, S. dumerili skin and mucus had a relatively high weight-percentage of C16:0, C18:1(n-9), C18:0 and C22:6(n-3) fatty acids. When S. dumerili were fed a diet supplemented with [13C] fatty acids, [13C] fatty acids were detected in S. dumerili skin and adult N. girellae on S. dumerili, but no [13C] fatty acids were detected in the S. dumerili cutaneous mucus. In addition, the epidermis of S. dumerili, attached with N. girellae, was markedly thin. These results suggest that N. girellae feeds primarily on host epithelial cells. We then infected 2 host fishes, S. dumerili and the spotted halibut Verasper variegatus (Pleuronectidae; a host less susceptible to N. girellae infection), and compared the fatty acid composition of N. girellae with that of the skin and cutaneous mucus of the hosts. The fatty acid profiles from all samples were qualitatively and quantitatively similar. Thus, the fatty acid composition of the host may not contribute to the difference in susceptibility between S. dumerili and V. variegatus. These results may serve to develop new strategies for the control of N. girellae infections.
新贝尼登虫（Neobenedenia girellae）是一种冠鞭毛虫单殖吸虫，是一种具有破坏性的鱼类寄生虫。我们研究了新贝尼登虫以及其宿主鱼类杜氏鰤（Seriola dumerili，鲹科）的皮肤和皮肤黏液中的脂质含量和脂肪酸组成。成年新贝尼登虫的脂质含量不到其宿主皮肤和皮肤黏液脂质含量的四分之一。成年新贝尼登虫、杜氏鰤的皮肤和黏液中，十六烷酸（C16:0）、油酸（C18:1(n - 9)）、硬脂酸（C18:0）和二十二碳六烯酸（C22:6(n - 3)）的重量百分比相对较高。当给杜氏鰤投喂添加了[13C]脂肪酸的饲料后，在杜氏鰤的皮肤以及寄生于杜氏鰤的成年新贝尼登虫中检测到了[13C]脂肪酸，但在杜氏鰤的皮肤黏液中未检测到[13C]脂肪酸。此外，附着有新贝尼登虫的杜氏鰤表皮明显变薄。这些结果表明，新贝尼登虫主要以宿主上皮细胞为食。然后，我们感染了两种宿主鱼类，即杜氏鰤和星斑川鲽（Verasper variegatus，鲆鲽科；一种对新贝尼登虫感染较不敏感的宿主），并比较了新贝尼登虫与宿主皮肤和皮肤黏液的脂肪酸组成。所有样本的脂肪酸谱在定性和定量方面都相似。因此，宿主的脂肪酸组成可能不会导致杜氏鰤和星斑川鲽在易感性上的差异。这些结果可能有助于制定控制新贝尼登虫感染的新策略。
