Sex and age, but not blood parasite infection nor habitat, affect the composition of the uropygial gland secretions in European blackbirds

Díez‐Fernández, Alazne; Puente, Josué Martínez‐de la; Martı́n, José; Gangoso, Laura; López, Pílar; Soriguer, Ramón C.; Figuerola, Jordi

doi:10.1111/jav.02630

Cited by 11 publications

(6 citation statements)

References 64 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To test this, one could analyse the chemical composition of preen oil secreted by the incubating parent(s) compared to the chemical composition of the nest and surrounding environment (e.g. using headspace sampling; Díez‐Fernández et al ., 2021) and assess whether preen oil is more chemically similar to the environment than would be expected by chance.…”

Section: Recommendations For Future Researchmentioning

confidence: 99%

Olfactory camouflage and communication in birds

Grieves

Gilles

Cuthill³

et al. 2022

Biological Reviews

View full text Add to dashboard Cite

Smell is a sensory modality that is rarely considered in birds, but evidence is mounting that olfaction is an important aspect of avian behaviour and ecology. The uropygial gland produces an odoriferous secretion (preen oil) that can differ seasonally and between the sexes. These differences are hypothesized to function in olfactory camouflage, i.e. minimizing detection by nest predators (olfactory crypsis hypothesis), and/or intraspecific olfactory communication, particularly during breeding (sex semiochemical hypothesis). However, evidence for seasonal and sex differences in preen oil is mixed, with some studies finding differences and others not, and direct evidence for the putative function(s) of seasonal variation and sex differences in preen oil remains limited. We conducted a systematic review of the evidence for such changes in preen oil chemical composition, finding seasonal differences in 95% of species (57/60 species in 35 studies) and sex differences in 47% of species (28/59 species in 46 studies). We then conducted phylogenetic comparative analyses using data from 59 bird species to evaluate evidence for both the olfactory crypsis and sex semiochemical hypotheses. Seasonal differences were more likely in the incubating than non‐incubating sex in ground‐nesting species, but were equally likely regardless of incubation strategy in non‐ground‐nesting species. This result supports the olfactory crypsis hypothesis, if ground nesters are more vulnerable to olfactorily searching predators than non‐ground nesters. Sex differences were more likely in species with uniparental than biparental incubation and during breeding than non‐breeding, consistent with both the olfactory crypsis and sex semiochemical hypotheses. At present, the data do not allow us to disentangle these two hypotheses, but we provide recommendations that will enable researchers to do so.

show abstract

Section: Recommendations For Future Researchmentioning

confidence: 99%

Olfactory camouflage and communication in birds

Grieves

Gilles

Cuthill³

et al. 2022

Biological Reviews

View full text Add to dashboard Cite

show abstract

“…In summary, our findings support the idea that the preen gland may function in diverse contexts -from antiparasitic defense to sensory communication -within the same species. While already known to influence gland morphology (Moreno-Rueda 2010, Grieves et al 2019, Díez-Fernández et al 2021, Whittaker and Hagelin 2021, we highlighted that individual factors (e.g. sex, age, body size and condition, plumage color traits) also differed in their relative importance.…”

Section: Discussionmentioning

confidence: 67%

Individual and environmental factors influencing preen gland's morphology and physiology in the barn owl Tyto alba

Ançay,

Nicole,

San‐Jose

et al. 2024

Journal of Avian Biology

View full text Add to dashboard Cite

Avian preen gland helps birds cope with their environment, although its overall functioning remains unclear. We shed light on the complexity of the preen gland's functioning by studying how multiple factors associate with gland morphology (size and shape) and physiology (wax secreted) in barn owls Tyto alba. Individual factors (sex, breeding stage, body condition) were more important predictors of preen gland than environmental factors (temperature, humidity, brood size). Sex, depending on breeding stage in adults, influenced preen gland traits, pointing to the preen gland's regulation by sex hormones and a greater pressure on females to protect their eggs, offspring and themselves throughout reproduction. Adults and fledglings in better condition had larger glands, pointing to the existence of physiological costs. Temperature and humidity, in interaction with plumage coloration, also influenced but to a lesser extent preen gland traits, suggesting that melanin pigmentation and preen gland act as superseding mechanisms when protecting plumage against microorganisms. Finally, fledglings living in larger broods had larger glands, suggesting a role for the social environment in preen gland's functioning. Overall, our study supports the idea that preen gland functions in diverse biological contexts within the same species and is thus subject to multiple selective pressures.

show abstract

“…Apart from its antimicrobial properties, the uropygial secretion of birds might function in scenarios of chemical communication including that related to inadvertent social information ( Danchin et al, 2004 ; Caro et al, 2015 ; Mazorra-Alonso et al, 2021 ). Accordingly, variations in chemical composition have been described in association with individual characteristics including age, sex, and phenology ( Reneerkens et al, 2002 ; Leclaire et al, 2011a , b ; Amo et al, 2012a ; Díez-Fernández et al, 2021 ). Here, we have detected that the antimicrobial capacity of bacterial isolates differed depending on age, which might also be interpreted as a consequence of the age related variation of the chemical composition of the uropygial secretion between adults and nestlings.…”

Section: Discussionmentioning

confidence: 99%

Microbial infection risk predicts antimicrobial potential of avian symbionts

Martínez-Renau

Mazorra-Alonso²,

Ruiz‐Castellano³

et al. 2022

Front. Microbiol.

View full text Add to dashboard Cite

Symbiotic bacteria on animal hosts can prevent pathogenic bacterial infections by several mechanisms. Among them, symbiotic bacteria can indirectly enhance host’s immune responses or, directly, produce antimicrobial substances against pathogens. Due to differences in life-style, different host species are under different risks of microbial infections. Consequently, if symbiotic bacteria are somewhat selected by genetically determined host characteristics, we would expect the antimicrobial properties of bacterial symbionts to vary among host species and to be distributed according to risk of infection. Here we have tested this hypothesis by measuring the antimicrobial ability of the bacterial strains isolated from the uropygial-gland skin of 19 bird species differing in nesting habits, and, therefore, in risk of microbial infection. In accordance with our predictions, intensity and range of antimicrobial effects against the indicator strains assayed varied among bird species, with hole-and open-nesters showing the highest and the lowest values, respectively. Since it is broadly accepted that hole-nesters have higher risks of microbial infection than open nesters, our results suggest that the risk of infection is a strong driver of natural selection to enhance immunocompetence of animals through selecting for antibiotic-producing symbionts. Future research should focus on characterizing symbiotic bacterial communities and detecting coevolutionary processes with particular antibiotic-producing bacteria within-host species.

show abstract

Sex and age, but not blood parasite infection nor habitat, affect the composition of the uropygial gland secretions in European blackbirds

Cited by 11 publications

References 64 publications

Olfactory camouflage and communication in birds

Olfactory camouflage and communication in birds

Individual and environmental factors influencing preen gland's morphology and physiology in the barn owl Tyto alba

Microbial infection risk predicts antimicrobial potential of avian symbionts

Contact Info

Product

Resources

About