Chiu Ming-Chung, Huang Chin-Gi, Wu Wen-Jer, Shiao Shiuh-Feng
Department of Entomology,National Taiwan University,Taipei 106,Taiwan.
Parasitology. 2015 Jul;142(8):1130-42. doi: 10.1017/S0031182015000360. Epub 2015 Apr 20.
Parasitic castration is a strategy used by parasites to minimize damage to the host by consuming its reproductive system, which results in the morphological alteration of the host. We determined that the forewing shape and density of the antennal sensilla of field-collected adult male mantids (Hierodula formosana), infected by horsehair worms (Chordodes formosanus) was partially feminized (intersexuality), and both male and female mantids infected by horsehair worms exhibited allometric changes in their wings and walking legs. In addition, the testes of most infected male adults disappeared or reduced in size, whereas the number of ovarioles in infected female adults was unaffected. The infection mainly influenced the structures related to host reproduction and locomotion, suggesting unbalanced energy exploitation and the reduction of parasitic virulence. In addition, the intersexuality of infected male adults indicated that sexual differentiation in insects, which researchers have considered to be an autonomous process, was influenced by the infection. The similarity of the antennae of infected male adults with those of last-instar female nymphs suggested that parasitic juvenilization may cause such feminization, but the mechanism of parasitic influence on insect sex characteristics should be studied further.
寄生性去势是寄生虫采用的一种策略，通过消耗宿主的生殖系统来使对宿主的损害最小化，这会导致宿主的形态改变。我们确定，野外采集的成年雄性台湾斧螳（Hierodula formosana）若感染了台湾铁线虫（Chordodes formosanus），其前翅形状和触角感器密度会出现部分雌性化（雌雄间性），并且感染铁线虫的雄性和雌性螳螂的翅膀和步足都出现了异速生长变化。此外，大多数受感染成年雄性的睾丸消失或体积减小，而受感染成年雌性的卵巢小管数量未受影响。这种感染主要影响与宿主繁殖和运动相关的结构，表明能量利用不均衡以及寄生虫毒力降低。此外，受感染成年雄性的雌雄间性表明，昆虫的性别分化（研究人员曾认为这是一个自主过程）受到了感染的影响。受感染成年雄性的触角与末龄雌性若虫的触角相似，这表明寄生幼态化可能导致了这种雌性化，但寄生虫对昆虫性别特征的影响机制仍需进一步研究。
