Trypanosome infection in salamanders (order: Caudata) from eastern North America with notes on the biology of Trypanosoma ogawai in Ambystoma maculatum

Abstract

Using the haematocrit centrifuge technique, trypanosomes were detected in 85 of 971 (8.8%) salamanders. The prevalence ranged from about 1% (4 of 405) in 1984 to 26.1% (24 of 92) in 1981. Trypanosomes were found in Ambystoma maculatum, A. laterale, A. jeffersonianum × A. laterale triploid hybrids, and A. jeffersonianum. Detectable infections were not found in A. texanum, A. texanum × A. laterale hybrids, or Notophthalmus viridescens. Trypanosoma ogawai was isolated in A. maculatum and A. jeffersonianum and it was infective by blood inoculation. The trypanosome and its multiplication process in the salamander are redescribed. It multiplied by unequal binary fission and the progenies were a small epimastigote and a large trypomastigote. The trypanosome developed to the metatrypanosome stage in the crop of the leech Batracobdella picta in 9 days at 21 °C. Metatrypanosomes from leeches at 16 days after feeding were infective when inoculated into laboratory-raised salamanders.