Winters Andrew D, Langohr Ingeborg M, Souza Marcos D E A, Colodel Edson M, Soares Mauro P, Faisal Mohamed
Department of Fisheries and Wildlife,Michigan State University,East Lansing,Michigan 48824,USA.
Department of Pathobiological Sciences,Louisiana State University,Baton Rouge,Louisiana 70803,USA.
Parasitology. 2016 Jan;143(1):41-9. doi: 10.1017/S0031182015001420. Epub 2015 Nov 2.
A microsporidian infecting the skeletal muscle of hybrid jundiara (Leiarius marmoratus × Pseudoplatystoma reticulatum) in a commercial aquaculture facility in Brazil is described. Affected fish exhibited massive infections in the skeletal muscle that were characterized by large opaque foci throughout the affected fillets. Histologically, skeletal muscle was replaced by inflammatory cells and masses of microsporidial developmental stages. Generally pyriform spores had a wrinkled bi-layer spore wall and measured 4·0 × 6·0 µm. Multinucleate meronts surrounded by a simple plasma membrane were observed. The polar filament had an external membrane and a central electron dense mass. The development of sporoblasts within a sporophorous vesicle appeared synchronized. Ultrastructural observations and molecular analysis of 16S rDNA sequences revealed that the microsporidian was Pleistophora hyphessobryconis. This study is the first report of a P. hyphessobryconis infection in a non-ornamental fish.
描述了在巴西一家商业水产养殖设施中感染杂交军曹鱼（Leiarius marmoratus × Pseudoplatystoma reticulatum）骨骼肌的一种微孢子虫。受影响的鱼在骨骼肌中表现出大量感染，其特征是在整个受影响的鱼片上有大的不透明病灶。组织学上，骨骼肌被炎症细胞和微孢子虫发育阶段的团块所取代。一般来说，梨形孢子有一层有皱纹的双层孢子壁，大小为4.0×6.0微米。观察到多核裂殖体被一层简单的质膜包围。极丝有一层外膜和一个中央电子致密团块。孢子母细胞在孢子囊内的发育似乎是同步的。超微结构观察和16S rDNA序列的分子分析表明，该微孢子虫是嗜鱼多孢虫。本研究是嗜鱼多孢虫在非观赏鱼中感染的首次报道。
