First report of equine Setaria digitata (von Linstow 1906) infestation in Malaysia

Vet Parasitol Reg Stud Reports. 2019 Aug:17:100310. doi: 10.1016/j.vprsr.2019.100310. Epub 2019 May 31.

Abstract

The occurrence of Setaria digitata in a horse is reported for the first time in Malaysia. An 8-year-old Thoroughbred cross mare was referred to the University Veterinary Clinic with the primary complaint of corneal opacity and excessive eye discharge. After initial treatment with Terramycin eye ointment, corneal opacity cleared partially to reveal a moving thread-like cylindrical worm in the anterior chamber of the eye. The parasite was successfully removed surgically, and examination under the light microscope revealed that the isolated worm (length = 45 mm) was a 5th stage larva of S. digitata based on morphological criteria. Confirmation of the species of the worm was through molecular methods. The 12S rRNA gene was PCR-amplified, and the purified amplicon was directly sequenced. Phylogenetic analyses revealed that the isolated roundworm showed 100% sequence similarity with that of S. digitata in NCBI GenBank database (Accession no.: KY284626.1). This report is the first confirmed case of equine ocular setariasis by S. digitata in Malaysia. The current study provides evidence that S. digitata is an etiological agent of ocular infection and its presence in Malaysia.

Keywords: 12S rRNA; Eye worm; Horse; Kelantan; PCR.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anterior Chamber / parasitology
  • Anterior Chamber / surgery
  • Anti-Bacterial Agents / therapeutic use
  • Base Sequence
  • DNA, Helminth / chemistry
  • DNA, Helminth / isolation & purification
  • Eye Infections, Parasitic / diagnosis
  • Eye Infections, Parasitic / parasitology
  • Eye Infections, Parasitic / surgery
  • Eye Infections, Parasitic / veterinary*
  • Female
  • Horse Diseases / diagnosis
  • Horse Diseases / drug therapy
  • Horse Diseases / parasitology*
  • Horses
  • Larva / anatomy & histology
  • Larva / classification
  • Malaysia
  • Ointments
  • Oxytetracycline / therapeutic use
  • Phylogeny
  • Polymerase Chain Reaction / veterinary
  • RNA, Ribosomal / genetics
  • Setaria Nematode / anatomy & histology
  • Setaria Nematode / classification
  • Setaria Nematode / genetics
  • Setaria Nematode / isolation & purification*
  • Setariasis / diagnosis*
  • Setariasis / parasitology
  • Setariasis / surgery

Substances

  • Anti-Bacterial Agents
  • DNA, Helminth
  • Ointments
  • RNA, Ribosomal
  • RNA, ribosomal, 12S
  • Oxytetracycline