Goater C P, Ward P I
Zoologisches Museum der Universität Zürich, Winterthurerstrasse 190, 8057, Zürich, Switzerland.
Oecologia. 1992 Feb;89(2):161-165. doi: 10.1007/BF00317213.
The growth and survival of juvenile toads, Bufo bufo, infected with a common lung nematode, Rhabdias bufonis, were studied. Toads were raised from tadpoles in the laboratory and infected 2 months after metamorphosis. Individual toads were exposed to doses of 10, 40, 80 or 160 larvae, which enabled examination of the hypothesis that parasite-induced mortality is affected by worm numbers. Growth of infected toads began to diverge from that of uninfected controls at 6 weeks post infection (WPI) and by 12 WPI the most heavily infected toads were approximately half the mass of controls. No controls died throughout the experiment; however, mortality of infected toads was strongly affected by parasite density. A mechanism for mortality is suggested by the significant negative relationship between parasite density and dietary intake. This parasite-induced anorexia was detected at 3 WPI and persisted up to 9 WPI. Patterns of reduced host growth, survival and dietary intake provide experimental evidence of the negative consequences of parasitic infection in a natural parasite-host system which may also be present under natural conditions.
对感染常见肺线虫——蟾蜍类圆线虫（Rhabdias bufonis）的中华大蟾蜍（Bufo bufo）幼蟾的生长和存活情况进行了研究。蟾蜍在实验室中由蝌蚪饲养长大，变态后2个月进行感染。将个体蟾蜍暴露于10、40、80或160条幼虫的剂量下，从而能够检验寄生虫诱导的死亡率受蠕虫数量影响这一假设。感染蟾蜍的生长在感染后6周（WPI）开始与未感染的对照组出现差异，到12 WPI时，感染最严重的蟾蜍体重约为对照组的一半。在整个实验过程中，没有对照组死亡；然而，感染蟾蜍的死亡率受到寄生虫密度的强烈影响。寄生虫密度与饮食摄入量之间的显著负相关关系提示了一种死亡机制。这种寄生虫诱导的厌食在3 WPI时被检测到，并持续到9 WPI。宿主生长、存活和饮食摄入量降低的模式为自然寄生虫 - 宿主系统中寄生虫感染的负面后果提供了实验证据，这种负面后果在自然条件下可能也存在。
