Translator Disclaimer
21 April 2021 Comparison of In-Clinic Diagnostic Testing Methods for Macrorhabdus ornithogaster
Hamish R. Baron, Ben C. Stevenson, David N. Phalen
Author Affiliations +

Macrorhabdus ornithogaster is an ascomycete yeast often found at the isthmus of the ventriculus and proventriculus of infected birds. Antemortem diagnosis has traditionally involved direct visualization of organisms on wet-mount or gram-stained fecal preparations, cloacal and crop swabs, or by both methods; however, different in-clinic diagnostic techniques have never been compared to establish an optimum test for the identification of M ornithogaster in an avian patient. We compared 5 microscopically evaluated diagnostic testing methods: fecal Gram's stain, direct fecal wet preparation, macro suspension technique, macro suspension with Gram's stain, and macro suspension stained with new methylene blue. Each technique was performed on 96 fecal samples collected during the treatment of M ornithogaster–infected budgerigars with water-soluble amphotericin B. The macro suspension technique produced statistically higher organism counts than the other 4 techniques and was always estimated to have the largest detection probability. We recommend that the macro suspension technique be implemented as the most efficacious diagnostic test for in-clinic assessment of avian patients possibly infected with M ornithogaster.

© 2021 by the Association of Avian Veterinarians
Hamish R. Baron, Ben C. Stevenson, and David N. Phalen "Comparison of In-Clinic Diagnostic Testing Methods for Macrorhabdus ornithogaster," Journal of Avian Medicine and Surgery 35(1), 37-44, (21 April 2021).
Published: 21 April 2021

Get copyright permission
Back to Top