Chaunus bergi (NCN) Endoparasites

GONZÁLEZ, C. E. Y M. I. HAMANN

HERPETOLOGICAL REVIEW

Society for the study of Amphibians and Reptiles.

Año: 2007 vol. 38 p. 181 - 181

0018-084X

 Twenty adults (7 females, 13 males) of C. bergi were collected in Corrientes, Argentina (27°28’S - 58°50’W) during September 2002 to November 2003. Fifteen amphibians were parasited (prevalence 75%) for three species of nematodes: Rhabdias sp. localized in the lung, hundred twenty-three Cosmocerca podicipinus localized in the large and small intestine and in the lung, and hundred twenty-two Cosmocerca parva localized in the large and small intestine. These nematodes possess a direct life cycle. The adults of Rhabdias spp., located in the lung, are protandrous hermaphrodite, the eggs deposited in lungs and passes in faeces of the host. In some hosts, first-stage larvae generally develop directly into second and then infective third-stage larvae (homogonic development); in the other host, free living stages which result in reproducing adults that eventually lead to infective larvae (heterogonic development). In amphibians, the third-stage larvae infected the host by skin penetration and lose their sheaths during the process. In the genus Cosmocerca the females produce thin-shelled eggs and the final host becomes infected by skin penetration. A lung migration is apparently a necessary part of the development in this genus.