Ultrastructural studies on Setaria digitata by scaning electron microscopy

Area of Science:

• Veterinary Parasitology
• Scanning Electron Microscopy
• Nematology

Background:

• Setaria species are common nematodes found in the peritoneal cavities of various ruminants.
• Accurate identification of Setaria species is crucial for understanding parasitic infections in livestock.
• Previous studies have described Setaria morphology, but detailed ultrastructural analysis using SEM is less common.

Purpose of the Study:

• To investigate and document the ultrastructural morphology of adult male and female Setaria worms.
• To identify the specific Setaria species infecting bovines in the Hyderabad region using detailed morphological characteristics.

Main Methods:

• Adult male and female Setaria worms were collected from the peritoneal cavities of slaughtered bovines.
• Specimens were examined using scanning electron microscopy (SEM) to observe surface structures.
• Detailed analysis of anterior and posterior end morphology, including papillae and cuticular features, was performed.

Main Results:

• SEM revealed a distinct peribuccal crown with a round mouth opening and lateral appendages at the anterior end.
• The cuticle displayed bosses and fine striations across the entire body surface.
• The posterior end of the female worm featured a round knob with lateral appendages, while the male exhibited complex cloacal papillae and a single spicule.

Conclusions:

• The observed ultrastructural features, particularly the arrangement of papillae and cuticular ornamentation, are characteristic of Setaria digitata.
• This study provides detailed SEM-based morphological data that aids in the definitive identification of Setaria digitata in bovines.
• The findings contribute to the taxonomic understanding of parasitic nematodes affecting livestock in India.