Pryor GS
ZOO BIOLOGY
22 (2): 163-177 2003
Abstract:
Dietary protein deficiency is considered a major obstacle in the evolution of highly specialized nectarivorous and frugivorous birds. Proposed physiological mechanisms that enable such specialists to subsist on low-protein diets include minimized endogenous protein losses, which contribute to reduced protein requirements. I compared these traits among nectarivorous red lories (Eos bornea), frugivorous Pesquet's parrots (Psittrichas fulgidus), and granivorous budgerigars (Melopsittacus undulatus). My results suggest that, relative to budgerigars, red lories and Pesquet's parrots have low endogenous protein losses and reduced crude protein (CP) requirements.
Based on nitrogen balance analyses, diets containing 1.0%, 3.2%, and 8.2% CP (on a dry matter (DM) basis) would meet the minimal protein requirements for maintenance for red lories, Pesquet's parrots, and budgerigars, respectively. Low endogenous protein losses and reduced protein requirements are effective physiological adaptations that allow birds such as red lories and Pesquet's parrots to specialize on low-protein foods.
(C) 2003 Wiley-Liss, Inc.
Author Keywords:
nitrogen, frugivores, granivores, nectarivores, specialists
KeyWords Plus:
FRUGIVOROUS BIRDS, PASSERINE BIRDS, FLESHY FRUITS, AMINO-ACIDS, WILD BIRDS, NITROGEN, NECTAR, HUMMINGBIRDS, MAINTENANCE, ADAPTATIONS
Addresses:
Pryor GS, Univ Florida, Dept Zool, Gainesville, FL 32611 USA
Univ Florida, Dept Zool, Gainesville, FL 32611 USA
Publisher:
WILEY-LISS, DIV JOHN WILEY & SONS INC, 605 THIRD AVE, NEW YORK, NY 10158-0012 USA
IDS Number:
669ZL
ISSN:
0733-3188
http://www.freeparrots.net/article.php?story=20031221071200208