Genetic barcoding of marine leeches (Ozobranchus spp.) from Florida sea turtles and their divergence in host specificity
DNA barcoding study published in Molecular Ecology Resources (2010)
Abstract
Ozobranchus margoi and Ozobranchus branchiatus are the only two species of marine turtle leeches (Ozobranchus spp.) known to inhabit the Atlantic coast of the United States and the Gulf of Mexico. In early reports of fibropapillomatosis (FP) in green turtles (Chelonia mydas), O. branchiatus was implicated as a vector in the transmission of Fibropapilloma-associated turtle herpesvirus (FPTHV). It is imperative that the leech species be identified to elucidate the role Ozobranchus spp. may play in disease transmission. In this study, Ozobranchus branchiatus has been identified for the first time on a loggerhead (Caretta caretta) turtle, and the molecular data for this species is now available for the first time in GenBank. Both species of leeches were also found infecting a single C. mydas. Using morphological taxonomy combined with distance- and character-based genetic sequence analyses, this study has established a DNA barcode for both species of Ozobranchus spp. leech and has shown it can be applied successfully to the identification of leeches at earlier stages of development when morphological taxonomy cannot be employed. The results suggest a different haplotype may exist for O. branchiatus leeches found on C. caretta versus C. mydas. Leech cocoon residue collected from a C. mydas was identified using the new method.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
DNA barcoding of marine turtle leeches Ozobranchus margoi and O. branchiatus reveals host-specific haplotypes; implicates these leeches as vectors of fibropapilloma-associated herpesvirus.
Why This Matters for Hirudotherapy
This study established DNA barcodes for two marine turtle leech species, Ozobranchus margoi and O. branchiatus, using morphological taxonomy combined with distance- and character-based genetic sequence analyses. The authors report the first record of O. branchiatus on a loggerhead turtle (Caretta caretta), document both species co-infecting a single green turtle, suggest a possible haplotype difference between O. branchiatus from different turtle hosts, and note the relevance to investigating these leeches as potential vectors of Fibropapilloma-associated turtle herpesvirus. The study is taxonomic and disease-ecological in nature, involving marine ectoparasitic leeches with no connection to medicinal leech use, hirudotherapy, or the therapeutic leech secretome. Its relevance to ASH's domain is negligible beyond illustrating diversity within the broader leech clade.
Citation
Genetic barcoding of marine leeches (Ozobranchus spp.) from Florida sea turtles and their divergence in host specificity.
McGowin AE et al. · Molecular ecology resources, 2010
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