ABSTRACT
Cystoisospora suis is a pathogen that causes diarrhea in pigs and can lead to serious disease. Species identification, especially by histopathological examination, is often difficult because of morphologically similar parasites such as Eimeria species. In this study, we used histopathological, bacteriological, virological, and parasitological methods to identify the cause of the disease in two piglets with severe diarrhea. Villous atrophy, diffuse necrosis, and flattening of mucosal epithelial cells were found in the ilea of examined piglets, and coccidian parasites were found in the cytoplasm of the epithelial cells. In some merozoites in the meronts, the presence of two nuclei indicated type 1 merozoites, characteristic of C. suis. According to Cystoisospora-specific PCR targeting the rRNA internal transcribed spacer 1 (ITS1) gene, the sequences of the products were 98.5% similar to those of C. suis. Escherichia coli (O149 serogroup) exhibiting a virulence factor profile (LT, STb, and EAST1 as toxins and F4 as a colonization factor) was detected in one piglet. No other bacteria or significant enteric viruses were found. Co-infection with C. suis and E. coli could imply aggravation of the disease, although further study is needed to assess the pathogenicity of this interaction. This study is the first to clarify by molecular analysis the sequences of C. suis detected in piglets in Japan.
Subject(s)
Coccidiosis/veterinary , Diarrhea/veterinary , Sarcocystidae/isolation & purification , Swine Diseases/parasitology , Animals , Cluster Analysis , Coccidiosis/parasitology , Coccidiosis/pathology , DNA, Protozoan/chemistry , DNA, Protozoan/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Diarrhea/parasitology , Diarrhea/pathology , Epithelial Cells/parasitology , Histocytochemistry , Ileum/pathology , Japan , Phylogeny , Polymerase Chain Reaction , Sarcocystidae/classification , Sarcocystidae/genetics , Sequence Analysis, DNA , Swine , Swine Diseases/pathologyABSTRACT
We evaluated the immunotoxicity of deoxynivalenol (DON), a Fusarium mycotoxin, on bovine and porcine neutrophils in vitro by using two function parameters, luminol-dependent chemiluminescence and random migration under agarose. A 2-hr DON treatment suppressed the chemiluminescence of bovine and porcine cells by 42% and 35% (on average) at 10(-5)M, and by 19% and 26% at 10(-6)M. Slight suppression was observed at concentrations lower than 10(-6)M. However, after an 18-hr DON treatment, random migration of neutrophils of both species remained unaffected, even at the highest concentration (10(-5)M). Although further extensive studies are needed, to our knowledge this is the first study to have revealed in vitro that DON can affect neutrophil function.
