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Background There has been considerable confusion concerning the number and classification of Sarcocystis spp. in chickens. Scarce nucleotide data of Sarcocystis spp. from chickens are provided in GenBank. The study aimed to investigate the morphological and molecular characteristics of Sarcocystis spp. found in chickens in China. Methods Tissues from 33 chickens were collected in 2019. Sarcocysts were observed using light (LM) and transmission electron microscopy (TEM). Individual sarcocysts from different chickens were selected for DNA extraction, and five loci, 18S rDNA, 28S rDNA, ITS1 region, the mitochondrial cox1 gene and the apicoplastic rpoB gene, were amplified from each sarcocyst, sequenced and analyzed. Results Only S. wenzeli was found in 14 of 33 (42.4%) chickens. Under LM, the sarcocysts were microscopic and exhibited palisade-like villar protrusions measuring 1.5–2.8 μm. Ultrastructurally, the sarcocyst wall contained numerous stubby hill-like villar protrusions. The protrusions included scattered microtubules, which extended from the tips of the protrusions into the ground substance. The five loci were successfully sequenced and the sequences deposited in GenBank. At 18S rDNA, ITS1 and cox1, the most similar sequences in GenBank were those of Sarcocystis sp. obtained from the brains of chickens, i.e. 99.9–100%, 98.1–98.5% and 99.3% identity, respectively. The five loci (18S rDNA, 28S rDNA, ITS1, cox1 and rpoB) showed different levels of interspecific sequence similarity with other closely related species of Sarcocystis (e.g. 99.8%, 99.0–99.2%, 89.3–89.7%, 98.5%, and 97.5%, respectively, with S. anasi). Phylogenetic analysis based on four of the loci (18S rDNA, cox1, rpoB and ITS1) revealed that S. wenzeli formed an independent clade with Sarcocystis spp. that utilize geese or ducks as intermediate hosts and canines as the known or presumed definitive host. Conclusions To our knowledge, the sequences of 28S rDNA and rpoB reported here constitute the first records of genetic markers of Sarcocystis spp. in chickens. Based on molecular analysis, S. wenzeli might be responsible for the neurological disease in chickens, and ITS1 and rpoB are more suitable for discriminating it from closely related Sarcocystis spp. Phylogenetic analysis revealed that S. wenzeli presents a close relationship with Sarcocystis spp. in geese or ducks.

Three cyst-forming Sarcocystis species have been identified in horsemeat; however, there exists considerable confusion concerning their relationships. Here, 74% (34/46) of the examined tissue samples from horses contained sarcocysts based on examination by light microscopy (LM), and the organism was identified as Sarcocystis bertrami based on cyst structure. The S. bertrami cysts were microscopic (up to 6750 μm in length) and exhibited a striated wall with 2.0–5.1 μm villar protrusions (vps) under LM. Transmission electron microscopy (TEM) observations showed that the vps were tightly packed, similar to “type 11c”. Four genetic markers (18S, 28S, ITS1 and the mitochondrial cox1 gene) of S. bertrami were sequenced and analyzed. The 28S and ITS1 sequences are the first records for Sarcocystis in horses. The newly obtained sequences of the 18S and cox1 genes both shared the highest similarities with those of S. bertrami and S. fayeri obtained from horses. Phylogenetic analysis based on the 18S, 28S and cox1 sequences revealed that S. bertrami and S. fayeri formed an independent clade within a group comprising Sarcocystis spp. from ruminants and pigs. Therefore, S. bertrami and S. fayeri are considered to represent the same species of Sarcocystis in horses, and S. fayeri is a junior synonym of Sarcocystis bertrami.

We report a draft sequence of the genome of Gordonia neofelifaecis NRRL B-59395, a cholesterol-degrading actinomycete isolated from fresh feces of a clouded leopard (Neofelis nebulosa). As predicted, the reported genome contains several gene clusters for cholesterol degradation. This is the second available genome sequence of the family Gordoniaceae.

Background: There has been considerable confusion concerning the number and classification of Sarcocystis spp. found in chickens. To date, no nucleotide sequences of Sarcocystis spp. from chickens have been provided in GenBank. The present study aimed to investigate the morphological and molecular characteristics of Sarcocystis spp. in chickens in China.Methods: Tissues from 33 chickens were collected in 2019. Sarcocysts were observed using light (LM) and transmission electron microscopy (TEM). Individual sarcocysts from different chickens were selected for DNA extraction, and five loci, 18S rDNA, 28S rDNA, the ITS-1 region (ITS-1), the mitochondrial cox1 gene (cox1), and the apicoplastic rpoB gene (rpoB), were amplified from each sarcocyst, cloned, sequenced and analyzed.Results: Only S. wenzeli was found in 14 of 33 (42.4%) chickens. Under LM, the sarcocysts were microscopic and exhibited palisade-like villar protrusions measuring 1.5–2.8 μm. The bradyzoites were lancet-shaped, measuring 9.2–12.6 × 1.5–3.5 μm. Ultrastructurally, the sarcocyst wall contained numerous stubby hill-like villar protrusions that were up to 1.2 μm long and 1.0 μm wide. The protrusions included scattered microtubules, which extended from the tips of the protrusions into the ground substance. The intraspecific similarity of the five loci (18S rDNA, 28S rDNA, ITS-1, cox1, and rpoB) among the newly obtained sequences ranged from 99.8–100%, 99.7–100%, 99.0–99.9%, 100% and 98.9–100%, respectively. The five loci showed different levels of interspecific sequence similarity with closely related species of Sarcocystis (e.g., 99.8%, 99.0–99.2%, 89.3-89.7%, 98.5%, and 97.5%, respectively, with S. anasi). Phylogenetic analysis based on three of the loci (18S rDNA, cox1, and rpoB) revealed that S. wenzeli formed an independent clade with Sarcocystis spp. that employ geese or ducks as intermediate hosts and canines as the known or presumed definitive host.Conclusions: The sequences of 18S rDNA, 28S rDNA, ITS-1, cox1 and rpoB from S. wenzeli reported here constitute the first records of genetic markers of Sarcocystis from chickens made available in GenBank. Based on sequence analysis, ITS-1 and rpoB are more suitable for discriminating S. wenzeli from closely related species of Sarcocystis. Phylogenetic analysis revealed that S. wenzeli presents a close relationship with Sarcocystis spp. from geese or ducks.