Prevalence of the microsporidian parasite (Thelohania contejeani) in crayfish across Ohio watersheds

Hannah G. Gill, Ohio Northern University
Haley Goehring, Ohio Northern University
Hannah Vance, Ohio Northern University
Emily Gremling, Ohio Northern University
Steven Churchin, Ohio Northern University
Tyler Koncsol, Ohio Northern University
Emily Imhoff, Ohio Environmental Protection Agency

Abstract

The parasitic microsporidian, Thelohania contejeani, causes porcelain disease (PD) in crayfish. T. contejeani infects the host's muscle tissues, resulting in loss of movement and ultimately death. This pathogen was first reported from Ohio in 2019. Here, molecular methods were used to survey for T. contejeani across three Ohio watersheds, the Muskingum (N= 76), Ohio (N=6), and Maumee (N= 24) Rivers. Crayfish were collected between August and November in 2021. The crayfish were tested for pathogen presence using 95% ethanol preserved tail muscle tissue. Total genomic DNA (gDNA) was extracted from tissue using a Qiagen DNeasy Blood and Tissue Kit®. The internal transcribed spacer (ITS1) gene of microsporidia was amplified via the polymerase chain reaction (PCR) using gDNA as template. Successful microsporidia amplifications then served as template in subsequent PCR reamplifications using primers specific for T. contejeani. Rates of infection were estimated by calculating the proportion of individuals positive for T. contejeani. A total of 10 crayfish tested positive for T. contejeani. In Symmes Creek, a tributary of the Ohio River, 67% of crayfish were positive for T. contejeani. In the Maumee River watershed, 31% of Ottawa River crayfish were positive for T. contejeani, while 18% were pathogen positive in Riley Creek. DNA sequencing will be used to confirm T. contejeani infection. Crayfish will also be DNA barcoded since species might be differentially susceptible to PD, information that could be utilized for future research and conservation efforts.

 
Apr 22nd, 10:00 AM Apr 22nd, 11:00 AM

Prevalence of the microsporidian parasite (Thelohania contejeani) in crayfish across Ohio watersheds

ONU McIntosh Center; Activities Room

The parasitic microsporidian, Thelohania contejeani, causes porcelain disease (PD) in crayfish. T. contejeani infects the host's muscle tissues, resulting in loss of movement and ultimately death. This pathogen was first reported from Ohio in 2019. Here, molecular methods were used to survey for T. contejeani across three Ohio watersheds, the Muskingum (N= 76), Ohio (N=6), and Maumee (N= 24) Rivers. Crayfish were collected between August and November in 2021. The crayfish were tested for pathogen presence using 95% ethanol preserved tail muscle tissue. Total genomic DNA (gDNA) was extracted from tissue using a Qiagen DNeasy Blood and Tissue Kit®. The internal transcribed spacer (ITS1) gene of microsporidia was amplified via the polymerase chain reaction (PCR) using gDNA as template. Successful microsporidia amplifications then served as template in subsequent PCR reamplifications using primers specific for T. contejeani. Rates of infection were estimated by calculating the proportion of individuals positive for T. contejeani. A total of 10 crayfish tested positive for T. contejeani. In Symmes Creek, a tributary of the Ohio River, 67% of crayfish were positive for T. contejeani. In the Maumee River watershed, 31% of Ottawa River crayfish were positive for T. contejeani, while 18% were pathogen positive in Riley Creek. DNA sequencing will be used to confirm T. contejeani infection. Crayfish will also be DNA barcoded since species might be differentially susceptible to PD, information that could be utilized for future research and conservation efforts.