Morphology, Molecular Characteristics, and Demonstration of a Definitive Host for Sarcocystis rommeli from Cattle (Bos taurus) in China

• Published in: The Journal of parasitology Vol. 103; no. 5; pp. 471 - 476
• Main Authors: Hu, J. J, Huang, S, Wen, T, Esch, G. W, Liang, Y, Li, H. L
• Format: Journal Article
• Language: English
• Published: United States American Society of Parasitologists 01-10-2017; Allen Press Inc
• Subjects: Amplification; Animals; Bos taurus; Bovidae; Bubalus bubalis; Cat Diseases - parasitology; Cats; Cattle; Cattle Diseases - parasitology; China; Chloroform; Cloning; Cloning, Molecular; Cysts; Cytochrome; Cytochromes; Deoxyribonucleic acid; Divergence; DNA; DNA, Protozoan - chemistry; DNA, Protozoan - isolation & purification; Electron Transport Complex IV - genetics; Feces; Feces - parasitology; Felis catus; Freeze thaw cycles; Freezing; Genetic testing; Infections; Intestine, Small - parasitology; Laboratory animals; Life Cycle Stages; Light microscopy; Microscopy, Electron, Transmission - veterinary; Mitochondria - enzymology; Morphology; Optical microscopy; Parasitology; Phenols; Phylogenetics; Phylogeny; Polymerase chain reaction; Polymerase Chain Reaction - veterinary; Proteinase; Rattus norvegicus; Ribosomal DNA; RNA, Ribosomal, 18S - genetics; Sarcocystis - classification; Sarcocystis - genetics; Sarcocystis - growth & development; Sarcocystis - ultrastructure; Sarcocystis bovifelis; Sarcocystis bovini; Sarcocystis cruzi; Sarcocystis heydorni; Sarcocystis hirsuta; Sarcocystis hominis; Sarcocystis rommeli; Sarcocystis sinensis; Sarcocystosis - parasitology; Sarcocystosis - veterinary; Sequence Alignment - veterinary; Sequence Analysis, DNA; SYSTEMATICS-PHYLOGENETICS; Thawing; Transmission electron microscopy
• ISSN: 0022-3395; 1937-2345
• DOI: 10.1645/16-187

Sarcocysts of Sarcocystis rommeli were found for the first time in 6 of 34 (17.6%) cattle (Bos taurus) in China. With light microscopy, sarcocysts of S. rommeli were up to 1,130 μm long, with a striated, 4–8-μm-thick cyst wall. Using transmission electron microscopy, the villar protrusions (vp) were 4.7–5.2 × 0.2–0.3 μm, and 0.3–0.5 μm apart from each other. The vp contained microtubules extending from the top of the vp to the middle of the ground substance layer (gsl). A BLAST search of the near full-length 18S rRNA and partial mitochondrial cox1 sequences of S. rommeli revealed 98.7% identity and 99.2% identity with sequences of Sarcocystis bovini in GenBank, respectively. Two domestic cats (Felis catus) fed sarcocysts of S. rommeli shed oocysts/sporocysts in their feces with a prepatent period of 14 to 15 days; the partial mitochondrial cox1 sequences of these oocysts/sporocysts shared the high identities, that is, 99.4% and 99.5%, with cox1 sequences of S. rommeli sarcocysts and S. bovini sarcocysts, respectively. This is the first demonstration of a definitive host for S. rommeli.