Abstract

Myxobolus lentisuturalis is a myxozoan parasite of piscine muscle that has been described in goldfish (Carassius auratus) and Prussian carp (Carassius gibelio).^1-3 This report documents a naturally occurring infection of M. lentisuturalis in a population of farmed goldfish in the United States. Postmortem examination was performed on four affected goldfish. Gross findings included large cystic cavities along the dorsal midline filled with caseous exudate. Histopathology revealed myxozoan plasmodia and spores in the epaxial muscles with varying degrees of granulomatous and necrotizing myositis accompanied by lymphohistiocytic meningoencephalitis. Spore morphology and dimensions were consistent with M. lentisuturalis, as observed by light microscopy.^1,2 PCR and sequence analysis of the 18S rDNA of infected muscle samples from two goldfish confirmed the parasite to have 99–100% nucleotide identity to M. lentisuturalis sequences recovered from similar cases of this parasite infecting goldfish in China and Italy and Prussian carp in China.^1,2 This is the first reported case of M. lentisuturalis in the United States and furthers the understanding of the pathogenicity of this under-described parasite.

*Presenting author

Literature Cited

1.  Dyková I, Fiala I, Nie P. Myxobolus lentisuturalis sp. n. (Myxozoa: Myxobolidae), a new muscle-infecting species from the Prussian carp, Carassius gibelio from China. Folia Parasitol. 2002;49:253–258.

2.  Caffara M, Raimondi E, Florio D, Marcer F, Quaglio F, Fioravanti, ML. The life cycle of Myxobolus lentisuturalis (Myxozoa: Myxobolidae), from goldfish (Carassius auratus auratus), involves a Raabeia-type actinospore. Folia Parasitol. 2009;56:6–12.

3.  Lom J, Dyková I. Myxozoan genera: definition and notes on taxonomy, life-cycle terminology and pathogenic species. Folia Parasitol. 2006;53:1–36.