Morphological and Molecular Identifications of the Microbial Population Inhabiting the Feathers of the Domestic Pigeon at Different Ages, With Special Reference to the Antimicrobial Impact of Preen Secretions Against the Identified Microbes

Abstract

The present investigation aimed to analyze the microbial communities inhabiting the feathers of the domestic pigeons at different age stages through both isolation of bacteria and fungi (culture-dependent) and 16S rRNA and ITS amplicon sequencing for bacteria and fungi, respectively (culture-independent), then evaluate the antimicrobial properties of the preen gland secretions of these isolates. Feather samples were collected from pigeons at three different ages: juvenile, adult, and senescent. One hundred fifty microbial species were identified; 108 were bacterial, and 42 were fungal species. The dominant microbial populations were Bacillus pumilus, Pseudomonas aeruginosa, and Aspergillus flavus. The antimicrobial activities of the preen gland secretions were assessed for their respective MIC, MBC, and MFC assays, confirmed by DNA cleavage assay. The obtained results demonstrated that the preen secretions of juvenile individuals were more effective against microbial colonization than senescent birds, indicating a possible age-related decline in the efficiency of secretions with aging. The study emphasizes the ecological relevance of the gland secretions in maintaining plumage health status and preventing microbial colonization, which indicates a pivotal role in defensive mechanisms in combating bacterial and fungal invasion.