Molecular phylogeny of Psoroptes ovis isolated from ear canker in a domestic rabbit from South India
D Akilkumar1, Y Ajith2, Sasi Adithya3
1Department of Veterinary Clinical Medicine, Ethics and Jurisprudence, College of Veterinary and Animal Sciences (CVAS), Kerala Veterinary and Animal Sciences University (KVASU), Mannuthy, Thrissur, Kerala, 680651, India.
Background:
Ear canker in domestic rabbits is caused by infestations of non-burrowing parasitic mites, Psoroptes spp., but the specific species responsible for these infestations remains unclear. This study reports the clinical signs and performs the molecular characterization and phylogenetic analysis of Psoroptes ovis isolated from the ear canal of a domestic rabbit in South India.
Methods And Results:
A one-year-old rabbit from a farm that housed both goats and rabbits presented with thick, grayish-white debris in the ear canal for the past week. Clinical examination revealed crusty otitis lesions, and microscopic analysis confirmed the presence of male and female Psoroptes mites, along with their eggs. Using Polymerase Chain Reaction targeting the mitochondrial cytochrome oxidase subunit 1 gene, the mites were identified as P. ovis (GenBank accession No. PQ661168). Phylogenetic analysis employing Maximum likelihood method revealed two major clades, with the isolate of the study most closely related to the one from South Korea. Haplotype network analysis using Median‑Joining Network identified eight distinct haplotypes.
Conclusions:
This study confirms P. ovis as the causative agent of ear canker in domestic rabbits in South India and highlights its genetic similarity to isolates from other regions. The findings underscore the importance of molecular tools for accurate identification of mites. Further studies should focus on the molecular identification of Psoroptes spp. from diverse domestic animals and investigate the potential for cross-species transmission in mixed farming systems, particularly between rabbits and other livestock.
Insights
Psoroptes ovis mites cause ear canker in South Indian domestic rabbits. Molecular analysis confirmed the species and revealed genetic similarities to other Psoroptes ovis isolates globally.
Area of Science:
- Veterinary Parasitology
- Molecular Phylogenetics
- Rabbit Health
Background:
- Ear canker in domestic rabbits is linked to Psoroptes mites, but species identification is often unclear.
- This study investigates a case of ear canker in a domestic rabbit in South India.
Purpose of the Study:
- To identify the specific Psoroptes species causing ear canker in a domestic rabbit.
- To perform molecular characterization and phylogenetic analysis of the isolated mite.
- To understand the genetic relationship of the isolate with other Psoroptes populations.
Main Methods:
- Clinical examination and microscopic analysis of ear canal debris.
- Polymerase Chain Reaction (PCR) targeting the mitochondrial cytochrome oxidase subunit 1 gene for species identification.
- Phylogenetic analysis using Maximum Likelihood and Median-Joining Network methods.
Main Results:
- Clinical signs included thick, grayish-white debris and crusty otitis lesions.
- Microscopic analysis confirmed the presence of Psoroptes mites and eggs.
- Molecular identification confirmed the mite as Psoroptes ovis.
- Phylogenetic analysis showed the isolate is closely related to P. ovis from South Korea, with eight distinct haplotypes identified.
Conclusions:
- Psoroptes ovis is confirmed as the cause of ear canker in this South Indian rabbit.
- Molecular tools are crucial for accurate mite identification.
- Further research on Psoroptes transmission between domestic animals is recommended.
