@article{MuellerRailaAltenkampetal.2012,
  author    = {Mueller, K. and Raila, Jens and Altenkamp, Rainer and Schmidt, D. and Dietrich, R. and Hurtienne, Andrea and Wink, M. and Krone, O. and Brunnberg, Leo and Schweigert, Florian J.},
  title     = {Concentrations of retinol, 3,4-didehydroretinol, and retinyl esters in plasma of free-ranging birds of prey},
  series = {Journal of animal physiology and animal nutrition},
  volume    = {96},
  journal   = {Journal of animal physiology and animal nutrition},
  number    = {6},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {0931-2439},
  doi       = {10.1111/j.1439-0396.2011.01219.x},
  pages     = {1044 -- 1053},
  year      = {2012},
  abstract  = {This study investigated vitamin A compounds in the plasma of healthy free-ranging Central European raptors with different feeding strategies. Plasma samples of nestlings of white-tailed sea eagle [white-tailed sea eagle (WTSE), Haliaeetus albicilla) (n = 32), osprey (Pandion haliaetus) (n = 39), northern goshawk (Accipiter gentilis) (n = 25), common buzzard (Buteo buteo) (n = 31), and honey buzzard (Pernis apivorus) (n = 18) and adults of WTSE (n = 10), osprey (n = 31), and northern goshawk (n = 45) were investigated with reversed-phase-high-performance liquid chromatography (RP-HPLC). In WTSE, northern goshawks and common buzzards retinol were the main plasma component of vitamin A, whilst in ospreys and honey buzzards, 3,4-didehydroretinol predominated. The median of the retinol plasma concentration in the nestlings group ranged from 0.12 to 3.80 mu M and in the adult group from 0.15 to 6.13 mu M. Median plasma concentrations of 3,4-didehydroretinol in nestlings ranged from 0.06 to 3.55 mu M. In adults, northern goshawks had the lowest plasma concentration of 3,4-didehydroretinol followed by WTSE and ospreys. The plasma of all investigated species contained retinyl esters (palmitate, oleate, and stearate). The results show considerable species-specific differences in the vitamin A plasma concentrations that might be caused by different nutrition strategies.},
  language  = {en}
}
@article{MuellerAltenkampRailaetal.2011,
  author    = {M{\"u}ller, Kerstin E. and Altenkamp, Rainer and Raila, Jens and Schmidt, Daniel and Dietrich, Robert and Hurtienne, Andrea and Wink, Michael and Krone, Oliver and Brunnberg, Leo and Schweigert, Florian J.},
  title     = {Plasma concentration of alpha-tocopherol in different free-ranging birds of prey},
  series = {European journal of wildlife research},
  volume    = {57},
  journal   = {European journal of wildlife research},
  number    = {5},
  publisher = {Springer},
  address   = {New York},
  issn      = {1612-4642},
  doi       = {10.1007/s10344-011-0516-z},
  pages     = {1043 -- 1049},
  year      = {2011},
  abstract  = {In this study, we investigated the alpha-tocopherol plasma concentrations in healthy free-ranging nestlings of the white-tailed sea eagle (Haliaeetus albicilla) (n=32), osprey (Pandion haliaetus) (n=39), northern goshawk (Accipiter gentilis) (n=25), common buzzard (Buteo buteo) (n=31), and honey buzzard (Pernis apivorus) (n=18) as well as of free-ranging adults of the white-tailed sea eagle (n=10), osprey (n=31), and northern goshawk (n=45). alpha-Tocopherol plasma concentrations were determined by reverse-phase high-performance liquid chromatography. alpha-Tocopherol plasma concentrations in nestlings of osprey, white-tailed sea eagle, and northern goshawk did not differ significantly amongst the species, but the common buzzard and honey buzzard nestlings had significantly lower alpha-tocopherol plasma concentrations than nestlings of the other species (both P<0.001). Adult male ospreys and white-tailed sea eagles had significantly higher alpha-tocopherol concentrations compared to adult females (both P<0.005). Adult ospreys and northern goshawks had significantly higher alpha-tocopherol plasma concentrations compared to their nestlings (both P<0.001). In adult female northern goshawks, plasma concentrations of alpha-tocopherol increased significantly before egg laying (P<0.001). These results demonstrate alpha-tocopherol plasma concentrations in birds of prey to be species specific and influenced by age and reproductive status.},
  language  = {en}
}