Nutritional Content of the Diets of Free-living Scarlet Macaw Chicks in Southeastern Peru
Schubot Exotic Bird Health Center, Department of Veterinary Pathobiology, Texas A&M University, College Station, TX 77843, USA.Journal of Avian Medicine and Surgery (Impact Factor: 0.39). 03/2010; 24(1):9-23. DOI: 10.1647/1082-6742-24.1.9
To provide novel information on psittacine diets, we analyzed the texture, crude protein, crude fat, Ca, P (total), Mg, K, Na, S, Cu, Fe, and Zn concentrations of crop contents from 10 free-living scarlet macaw (Ara macao) chicks from lowland forests of southeastern Peru. We compared our results with nutrient concentrations of known wild parrot foods and published psittacine dietary recommendations to highlight similarities and differences and suggest future avenues of research. The diets were much coarser textured than those recommended for hand feeding. Soil in the diet provided an important source of Na, but Na levels were still lower than all recommendations. Concentrations of protein, Zn, K, Cu, and P (total) were near to or within the range of recommendations for captive psittacine birds. Fat, Ca, and Mg concentrations were greater in crop contents than in the average food plants and greater than published recommendations. The Na:K ratios were only one-twentieth of those recommended for young poultry. Future analyses should investigate the bioavailability of Fe, Ca, and Zn in these diets and the effects of varying concentrations of fat, Na, Ca, Mg, and Na:K ratio on psittacine growth and development.
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Possibly, a decrease in availability of non-starch polysaccharides, resulting from lower particle size reduction, contributed to improved firmness of droppings when fed the coarse pellets compared to the fine particle size pellets. In conclusion, provision of fruit effectively reduced voluntary energy intake in granivorous parrots without adverse effects on consumption of essential nutrients. This way, obesity can be safely abated even in group-housed parrots. In nectarivorous parrots, however, highly diluted nectar food can be lower in energetic density compared to fruit. Hence, ad libitum provision of fruit beside nectar does not necessarily lower the energy content of the ingested ration in nectar feeders. In green-naped and red-breasted lorikeets, lowest voluntary energy intake was attained when fed high dilution-nectar and low-dilution nectar added with fruit, respectively. 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