Uropygial gland volatiles may code for olfactory information about sex, individual, and species in Bengalese finches Lonchura striata

Over-shadowed by eye-catching vocal and visual signals, chemical communication has long been overlooked in birds. This study aimed at exploring whether volatile composition of the uropygial gland secretion (UGS) of birds was associated with the information about sex, individual and species. By using dichloromethane extraction and gas chromatography-mass spectrometry (GC-MS), we analyzed the UGS volatiles of domesticated Bengalese finches (Lonchura striata, Estrildiea) which is also known as white-rumped munias. We characterized 16 volatile molecules from the UGS, including eight n-alkanols, five diesters, an ester, an aldehyde and a fatty acid, and quantified them in terms of GC peak area percentages (relative abundances). Among these compounds, hexadecanol and octadecanol were major components in both sexes. The former was richer in males than in females and the latter richer in females than in males, suggesting that they might be male and female pheromone candidates, respectively. The high inter-individual variations, in relative abundance, of the UGS volatiles implied that these compounds might carry information about individuality. The similarity between GC profiles of the UGS and wing feather from same individuals indicates that the birds might preen the secretion to their feathers to transmit chemical cues. Additionally, by comparing with three sympatric passerine species, i. e., zebra finches Taeniopygia guttata, yellow-bowed buntings Emberiza chrysophrys and rooks Corvus frugilegus, we found that the composition of C13 - C18 alkanols in the UGS might code for information about species. Our study also showed that quantitative differences (degree) of same UGS volatiles might be the key for the Bengalese finch to code for information about sex and individuality whereas both the kind and degree of UGS constituents could be utilized to code for information about species.

The Structure of Preen Gland Waxes from Pelecaniform Birds Containing 3,7-Dimethyloctan-1-ol -an Active Ingredient against Dermatophytes

A biologically active principle has been isolated from the uropygial gland secretion of the gannet (Sula bassana) exhibiting growth inhibitory activity for Gram-positive bacteria, yeasts, moulds and, in particular, for dermatophytes.The feather lipids of this species consist of monoester waxes predominantly composed of 3,x-dimethylalkanols esterified with fatty acids belonging to homologous series of 2-and 3-methyl-, 2,x-and 3,x-dimethyl-as well as 2,x,y-and 3,x,y-trimethyl-substituted alkanoic acids. For chemosystematic reasons other pelecani­ form species (Pelecanus crispus, Pelecanus onocrotalus, Phaeton lepturus) and one gaviiform species (Gavia stellata) have also been analysed. The pattern of their preen wax constituents suggest to assume that the Pelecaniformes are polyphyletic with gannets and cormorants being closely related, whereas pelicans and tropic birds are different, both from the former and from each other. Pelicans resemble very much the grebes, while tropic birds seem to be more closely related to the charadriiform, alciform, and possibly to the gaviiform birds.