DAO 74:67-75 (2007)  -  doi:10.3354/dao074067

Characterization of a rediscovered haplosporidian parasite from cultured Penaeus vannamei

Linda M. Nunan1,*, Donald V. Lightner1, Carlos R. Pantoja1, Nancy A. Stokes2, Kimberly S. Reece2

1Department of Veterinary Science and Microbiology, University of Arizona, Tucson, Arizona 85721, USA
2School of Marine Science, Virginia Institute of Marine Science, College of William and Mary, Gloucester Point, Virginia 23062, USA

ABSTRACT: Mortalities of Penaeus vannamei, cultured in ponds in Belize, Central America, began during the last part of the grow-out cycle during the cold weather months from September 2004 through February 2005. Tissue squashes of infected hepatopancreata and histological examination of infected shrimp revealed that the mortalities might have been caused by an endoparasite. To confirm the diagnosis, DNA was extracted from ethanol preserved hepatopancreata and the small-subunit rRNA gene was sequenced. The 1838 bp sequence was novel and phylogenetic analysis placed the P. vannamei parasite within the phylum Haplosporidia as a sister taxon to a clade that includes Bonamia and Minchinia species. In situ hybridization was performed using anti-sense DNA probes that were designed to hybridize specifically with the parasite’s nucleic acid. This organism presents similar characteristics to those of a haplosporidian that infected cultured P. vannamei imported from Nicaragua into Cuba, as described by Dyková et al. (1988; Fish Dis 11:15–22).


KEY WORDS: Haplosporidian · Shrimp · Parasite · Molecular phylogenetic analysis


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