Can birds be ammonotelic? Nitrogen balance and excretion in two frugivores

  title={Can birds be ammonotelic? Nitrogen balance and excretion in two frugivores},
  author={Ella Tsahar and Carlos Martinez Del Rio and Ido Izhaki and Zeev Arad},
  journal={Journal of Experimental Biology},
  pages={1025 - 1034}
SUMMARY We measured minimal nitrogen requirements (MNR), total endogenous nitrogen loss (TENL) and the effect of protein and water intake on the nitrogenous waste composition in two frugivorous bird species: yellow-vented bulbuls Pycnonotus xanthopygos and Tristram's grackles Onychognathus tristrami. The nitrogen requirements of both species were much lower than expected for their body mass. The two species differed in the composition of the nitrogenous waste that they produced. The grackles… 

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