title: Kudoa thunni from blackfin tuna (Thunnus atlanticus) harvested off the island of St. Kitts, West Indies.
abstract: Numerous myxozoan cysts (∼ 1 mm) were found in the musculature of blackfin tuna (Thunnus atlanticus) harvested off the Caribbean island of St. Kitts. Myxospores were consistent with quadrate members of the Kudoidae, measuring 8.8 (8.2-9.4) μm wide, 7.3 (6.6-8.3) μm thick, and 6.2 (5.8-6.9) μm long with 4 uniform drop-like polar capsules measuring 2.7 (2.2-3.2) μm long and 2.0 (1.7-2.2) μm wide. The 18S small-subunit (SSU) and 28S large-subunit (LSU) ribosomal DNA sequences did not result in direct matches to any published sequences. However, the SSU sequences (1,786 base pairs [bp]) obtained from 6 individual cysts were identical and demonstrated high homology to Kudoa thunni (99.0%) from albacore (Thunnus alalunga). Alternatively, 33 unique sequences were obtained for the LSU (∼ 800 bp), demonstrating 0.1 to 5.0% variability between them, although a majority of these sequences (60%) demonstrated high homology (>99%) to K. thunni. Morphologically, the case isolate was smaller than published descriptions of K. thunni; however, rDNA sequence homology, and phylogenetic placement based on concatenated SSU and LSU rDNA sequences suggests this case isolate and K. thunni are conspecific. To our knowledge this is the first report of K. thunni infection in blackfin tuna from the Caribbean.
authors.affiliation: Department of Pathology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, Mississippi 38776.
authors.forename: Matt
authors.initials: M
authors.lastname: Griffin
authors.forename: Sylvie
authors.initials: S
authors.lastname: Quiniou
authors.forename: Cynthia
authors.initials: C
authors.lastname: Ware
authors.forename: Lewis
authors.initials: L
authors.lastname: Bogdanovic
authors.forename: Esteban
authors.initials: E
authors.lastname: Soto
mesh_terms: D000818:Animals; D001267:Atlantic Ocean; D001483:Base Sequence; D004275:DNA, Ribosomal / Q000737:chemistry; D005393:Fish Diseases / Q000469:parasitology*; D008969:Molecular Sequence Data; D018482:Muscle, Skeletal / Q000469:parasitology; D055764:Myxozoa / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D010273:Parasitic Diseases, Animal / Q000469:parasitology*; D010802:Phylogeny; D019437:Saint Kitts and Nevis; D012623:Seawater; D014413:Tuna / Q000469:parasitology*
chemical_list: D004275:DNA, Ribosomal