DOI: 10.5061/dryad.79cnp5j90
title: Data from: Species-specific and microbial variability in the antimicrobial efficacy of uropygial secretions in wild passerines

description: Uropygial secretions are thought to play an antimicrobial role in birds,
 but few studies have compared their effectiveness across multiple species
 and microorganisms using standardized methods. We evaluated the
 antimicrobial activity of uropygial secretions from 212 individuals of 11
 passerine species in southwestern Spain, testing their inhibitory effects
 against Bacillus licheniformis, B. subtilis, Candida albicans, Escherichia
 coli, and Salmonella typhimurium by flow cytometry. Antimicrobial activity
 varied significantly among species and microorganisms: house sparrows
 (Passer domesticus) consistently exhibited stronger and broader responses,
 whereas activity against S. typhimurium was generally low. Phylogeny,
 migratory status, and social behavior did not explain variation, but
 uropygial gland size was positively associated with antimicrobial activity
 both globally and in some bird species. Body condition exhibited
 species-specific associations with antimicrobial activity, showing
 positive correlations in some bird species and negative correlations in
 others. Overall, our findings highlight the uneven distribution of
 antimicrobial defenses among passerines and underscore the importance of
 comparative, chemically informed, and methodologically standardized
 approaches to clarify the ecological and evolutionary significance of
 uropygial secretions.
description: ## Files included ### a) **Mora-Rubio2025.csv** This **CSV file** contains
 the full dataset used in the analyses.\ Each row corresponds to an
 individual bird and its associated measurements and antimicrobial assay
 outcomes. #### Column descriptions * **ID_LabMarzal**\ Unique identifier
 assigned to each bird in the Marzal Lab database. * **Species**\ Species
 of the sampled bird * **Status**\ Migratory behavior of the species: *
 *migratory* – migratory species * *resident* – resident species *
 **Family**\ Taxonomic family of the bird (e.g., Paridae, Hirundinidae,
 Sylviidae). * **Volumegland**\ Volume of uropygial secretion used in the
 antimicrobial assays (in mm3). * **Tarsus**\ Tarsus length (mm). *
 **Weight**\ Body mass of the individual (g). * **Bodycondition**\ Body
 condition index calculated as the residuals of the regression of body mass
 on tarsus length. * **Bacteria**\ Species of the microorganism (bacterium
 or fungus) used in the antimicrobial test. --- #### Antimicrobial activity
 variables These columns represent **inhibition values** obtained under
 different assay conditions, varying both secretion volume and incubation
 time. * **ABA124**\ Antimicrobial activity using **1 µL of secretion** at
 **24 hours**. * **ABA148**\ Antimicrobial activity using **1 µL of
 secretion** at **48 hours**. * **ABA224**\ Antimicrobial activity using
 **2 µL of secretion** at **24 hours**. * **ABA248**\ Antimicrobial
 activity using **2 µL of secretion** at **48 hours**. These variables
 allow the assessment of microbicidal and microbiostatic effects across
 bird species, bacterial strains, secretion volumes, and incubation times.
 --- ### b) **Mora-Rubio_R_scripts.txt** This **plain text (.txt)** file
 contains all R scripts used to reproduce the statistical analyses and
 figures presented in the manuscript. #### Contents of the script file *
 Data import and cleaning steps for the csv file. * Calculation of the body
 condition index (residuals of mass ~ tarsus). * Identification and coding
 of antimicrobial vs. microbiostatic effects. * Statistical tests
 (non-parametric tests, GLMMs, post-hoc comparisons). ---