True Metabolizable Energy Estimates of Canada Goose Foods

Abstract

We determined true metabolizable energy (TME) and digestibility of 8 foods commonly available to Canada geese (Branta canadensis) in order to provide managers with a better understanding of the nutritional value of these foods. True metabolizable energy estimates were highest for chufa tubers (Cyperus esculentus ; 16.86 kJ/g), corn (Zea mays; 16.32 kJ/g), and milo (Sorghum vulgare; 15.72 kJ/g), while estimates for soybeans (Glycine max; 14.85 kJ/g), wild millet (Echinochloa crusgalli; 13.77 kJ/g), and rice (Oryza sativa; 11.76 kJ/g) were intermediate in value. Winter wheat foliage (Triticum aestivum; 10.04 kJ/g) and largeseed smartweed seeds (Polygonum pensylvanicum; 6.65 kJ/g) provided the least TME of foods tested. Crude fiber accounted for 76% of the variation in TME. Digestibility values of the 8 foods ranged from 35.1 to 88.5%, with digestibility varying widely among both agricultural and natural foods. To supply Canada geese with a balanced diet and foods high in metabolizable energy (ME), managers should provide a variety of agricultural and natural foods that are low in fiber content.