The uropygial gland of the Great Cormorant (Phalacrocorax carbo): II. Biochemical analysis of the uropygial secretion

Abstract In contrast to many other water birds, the Great Cormorant, Phalacrocorax carbo (Phalacrocoracidae), shows a typical wing-spreading behavior after diving. This has been linked partial wettability of Cormorant’s feathers based on unusual structure contour feathers. Close rachis, these have closed vane with very densely spaced barbs but an open in more peripheral feather parts. To investigate whether is connected composition uropygial gland secretion that often repellency bird feathers, we analyzed secretions Cormorant and, for comparison, Muscovy Duck, Cairina moschata (Anatidae). Using mass spectrometry techniques, atmospheric solids analysis probe-atmospheric pressure chemical ionization-mass (ASAP-APCI-MS) and gas chromatography/mass (GC/MS), significant differences were revealed. The showed highly diverse mixture than 1000 compounds consisting methyl-branched aliphatic carboxylic esters large chain length variability. contrast, duck’s dominated by two octadecyl eicosyl 2,4,6-trimethyloctanoate. Water contact angle measurements Duck higher Cormorant. Nevertheless, before removing waxes indicate waxes, likely secretions, did not influence degree.