New Diagnostic Insights for Macrorhabdus ornithogaster Infection

Abstract

The aim of this study was to propose the use of a new rapid and user-friendly diagnostic tool for the detection of Macrorhabdus ornithogaster infection in birds. The current report focuses on the diagnostic feasibility of different methods, with particular emphasis on the application of the mini-Flotac technique for the diagnosis of M. ornithogaster infection. The mini-Flotac method is particularly tailored for epidemiological monitoring and surveillance, where large numbers of fecal samples must be rapidly, yet reliably, examined. Gram staining, as the standard method, was used to validate the reliability of the mini-Flotac method. This tool has not yet been used in avian species or in the diagnosis of yeast infections. In our study, M. ornithogaster showed excellent performance in a flotation assay, which had not been demonstrated previously. Our results suggest that the mini-Flotac method is a valid, sensitive, and potentially low-cost alternative technique for use in the diagnosis of this yeast infection in birds.

FIG 1

Gram stained Macrorhabdus ornithogaster (arrow) from a fecal sample under a light microscope. Bar = 50 μm.

FIG 2

Macrorhabdus ornithogaster (a) (arrow) observed under a light microscope with use of the mini-Flotac tool (b). Bar = 50 μm.

FIG 3

Carduelis carduelis fecal sample examined under a light microscope with use of the mini-Flotac tool: concomitant infection with Isospora sp. (white arrow) and Macrorhabdus ornithogaster (black arrow). Bar = 20 μm.