Negative effects ofRhabdias bufonis(Nematoda) on the growth and survival of toads (Bufo bufo)

✍ Scribed by C. P. Goater; P. I. Ward

• Publisher: Springer-Verlag
• Year: 1992
• Tongue: English
• Weight: 561 KB
• Volume: 89
• Category: Article
• ISSN: 0029-8549
• DOI: 10.1007/bf00317213

✦ Synopsis

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.