Hostname: page-component-7c8c6479df-24hb2 Total loading time: 0 Render date: 2024-03-27T11:32:09.144Z Has data issue: false hasContentIssue false

Infection of Gammarus duebeni populations by two vertically transmitted microsporidia; parasite detection and discrimination by PCR–RFLP

Published online by Cambridge University Press:  16 January 2003

J. C. HOGG
Affiliation:
School of Biology, University of Leeds, Leeds LS2 9JT, UK
J. E. IRONSIDE
Affiliation:
School of Biology, University of Leeds, Leeds LS2 9JT, UK
R. G. SHARPE
Affiliation:
School of Biology, University of Leeds, Leeds LS2 9JT, UK
M. J. HATCHER
Affiliation:
School of Biological Sciences, University of Bristol, Bristol BS8 1UG, UK
J. E. SMITH
Affiliation:
School of Biology, University of Leeds, Leeds LS2 9JT, UK
A. M. DUNN
Affiliation:
School of Biology, University of Leeds, Leeds LS2 9JT, UK

Abstract

We screened a population of the brackish water crustacean Gammarus duebeni from the Isle of Cumbrae for the presence of vertically transmitted microsporidia. We compared 2 screening techniques; light microscopy and PCR-based detection using generic 16S rDNA microsporidian primers. Fifty percent of females from this population tested positive for vertically transmitted microsporidia. The PCR screen was 100% efficient in comparison with existing LM based screening. In addition, the PCR screen produced bands of 2 sizes suggesting that more than 1 species of microsporidian was present. Sequencing revealed 2 distinct species of vertically transmitted microsporidia; 33% of females were infected with the feminizer Nosema granulosis and 17% were infected with a new species which we provisionally designate Microsporidium sp. On the basis of sequence information, we developed a discriminatory PCR–RFLP test based on MspI and HaeIII digests. This screen allows rapid detection and discrimination of vertically transmitted microsporidia in natural field populations. We applied the PCR–RFLP screen to a second G. duebeni population from the Isle of Man. This population also hosted these 2 parasite species. In total 45% of females harboured N. granulosis and 10% harboured Microsporidium sp. No dual-infected individuals were found in either population. The occurrence of 2 vertically transmitted parasites within a population has implications for our understanding of parasite–host relationships in the field and we discuss factors affecting the dynamics of parasite–parasite competition and coexistence.

Type
Research Article
Copyright
2002 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)