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Home / Equine Research Bank / Parasit Vectors / The first mitogenome of Petrovinema skrjabini from Equus fer...
Parasites & vectors2025; 18(1); 278; doi: 10.1186/s13071-025-06851-7

The first mitogenome of Petrovinema skrjabini from Equus ferus przewalskii: a phylogenetic analysis within the Strongylidae family.

Abstract: Petrovinema skrjabini (Nematoda: Strongylidae, Cyathostominae) is a parasitic nematode colonizing the cecum and colon of equids. Like other cyathostomins, its larvae (L3) invade the intestinal mucosa, forming encysted nodules that may remain dormant for years. Mass larval emergence triggers larval cyathostominosis-a severe syndrome characterized by hemorrhagic typhlocolitis and diarrhea, with mortality rates exceeding 50%. However, owing to the morphological indistinguishability of cyathostomin and frequent mixed infections in natural settings, species-specific contributions to pathogenesis remain unresolved. Previous studies on P. skrjabini have predominantly focused on its morphology, with limited molecular information available. Methods: The complete mitogenome of Petrovinema skrjabini was sequenced using the Illumina NovaSeq 6000 platform, followed by assembly and annotation. We performed a phylogenetic analysis using Bayesian inference (BI) and maximum likelihood (ML) methods, based on 12 protein-coding genes from mitogenomes, to assess the evolutionary relationships of 34 Strongylidae species. Results: The complete mitogenome of P. skrjabini comprises 13,885 base pairs with 12 protein-coding genes, two ribosomal-RNA genes, 22 transfer-RNA genes, and two non-coding regions. The gene arrangement of the P. skrjabini mitogenome was consistent with the GA3 arrangement found in other Strongylidae species. The mitogenome exhibited a high AT bias (75.4%), which is consistent with other species in other Strongylidae species. Phylogenetic analysis showed that two Strongylus species (belonging to subfamily Strongylinae) formed a clade and located in the base of Strongylidae, while three Triodontophorus (belonging to subfamily Strongylinae) species and P. skrjabini formed another clade within in subfamily Cyathostominae within Strongylidae, based on 12 protein-coding genes from mitogenomes, suggesting that the genus Triodontophorus should transfer to the subfamily Cyathostominae. Conclusions: The characterization of the complete mitochondrial genomes of P. skrjabini is reported for the first time. This study provided helpful genetic markers for P. skrjabini identification and taxonomy, facilitating early nematode diagnosis and treatment to decrease equine parasitic nematode burdens. Our mitochondrial phylogeny analyses further corroborate the hypothesis that the genus Triodontophorus belongs to Cyathostominae. The present study enriches the database of strongylids mitogenomes and provides a new insight into the systematics of the family Strongylidae.
© 2025. The Author(s).
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Publication Date: 2025-07-11 PubMed ID: 40646541PubMed Central: PMC12247273DOI: 10.1186/s13071-025-06851-7Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research work focuses on the genetic analysis of Petrovinema skrjabini, a parasitic worm species found in horses, with the aim of providing genetic markers for better diagnosis of nematode infections and to refine the taxonomy of the family Strongylidae.

Objective and Importance of the Research

  • The key goal of the research is to analyze the mitochondrial genome, or mitogenome, of Petrovinema skrjabini – a parasitic nematode found in some horse species.
  • Understanding the complete genetic makeup of this worm species is crucial due to its potential fatal impact; mass hatching of its larvae could cause a severe syndrome in the horses with a mortality rate exceeding 50%.
  • Additionally, past studies on this species have been primarily morphological, while molecular information remains limited. Hence, this study might help fill in the gaps in molecular research on this nematode.

Methodology and Results

  • The mitogenome of P. skrjabini was sequenced using the Illumina NovaSeq 6000 platform, and assembled and annotated thereafter.
  • After the sequencing, a phylogenetic analysis was performed using Bayesian Inference and Maximum Likelihood methods. They assessed the evolutionary relationships of 34 species within the Strongylidae family based on 12 protein-coding genes.
  • The sequencing revealed that the complete mitogenome of P. skrjabini has 13,885 base pairs including 12 protein-coding genes, two ribosomal-RNA genes, 22 transfer-RNA genes, and two non-coding regions.
  • A high AT bias (75.4%) was also observed in the mitogenome of P. skrjabini, which is an expected trait in Strongylidae species.

Key Findings and Conclusion

  • The phylogenetic analysis gathered from the study revealed that two Strongylus species and three Triodontophorus species, together with P. skrjabini, formed distinct clusters within the Cyathostominae subfamily of the Strongylidae family.
  • This could suggest that the genus Triodontophorus should be transferred to the Cyathostominae subfamily, which offers a new perspective on the taxonomy of Strongylidae.
  • The first-ever reported characterization of the complete mitochondrial genomes of P. skrjabini provides useful genetic markers for this species’ identification and taxonomy.
  • This study facilitates early diagnosis and treatment of nematode infections, potentially reducing the burdens of equine parasitic nematodes.
  • The study enriches the genetic database of strongylids and offers a fresh insight into the taxonomy of the Strongylidae family.

Cite This Article

APA
Jia H, Tang L, Fu Y, Xiong Y, Yan L, Shao C, Li K, Zhang D, Hu D. (2025). The first mitogenome of Petrovinema skrjabini from Equus ferus przewalskii: a phylogenetic analysis within the Strongylidae family. Parasit Vectors, 18(1), 278. https://doi.org/10.1186/s13071-025-06851-7

Publication

Parasites & vectors
ISSN: 1756-3305
NlmUniqueID: 101462774
Country: England
Language: English
Volume: 18
Issue: 1
Pages: 278
PII: 278

Researcher Affiliations

Jia, Huiping
  • School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China.
Tang, Liping
  • School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China.
Fu, Yajun
  • School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China.
Xiong, Yu
  • School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China.
Yan, Liping
  • School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China.
Shao, Changliang
  • Xinjiang Kalamaili Mountain Ungulate Nature Reserve Management Center, Xinjiang, China.
Li, Kai
  • School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China.
Zhang, Dong
  • School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China. ernest8445@163.com.
Hu, Defu
  • School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China. hudf@bjfu.edu.cn.

MeSH Terms

  • Animals
  • Phylogeny
  • Genome, Mitochondrial
  • Equidae / parasitology
  • Strongyloidea / genetics
  • Strongyloidea / classification
  • Horses / parasitology
  • Horse Diseases / parasitology

Grant Funding

  • 2022YFC2601601 / The National Key R&D Program of China
  • 2019JQ0318 / The Beijing Forestry University Outstanding Young Talent Cultivation Project

Conflict of Interest Statement

Declarations. Ethics approval and consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests.

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