Suspected Macrorhabdosis during a Concurrent Salmonellosis Outbreak in a Wild Yellow-Rumped Warbler (Setophaga coronata).

We describe necropsy lesions of three adult Yellow-rumped Warblers (Setophaga coronata) diagnosed with salmonellosis during a Salmonella enterica serovar Typhimurium outbreak. One warbler had filamentous organisms consistent with Macrorhabdus ornithogaster at the proventricular-ventricular isthmus. There is limited information on Macrorhabdus ornithogaster infections in wild North American birds.