title: Nitrogen and energy requirements of the North American porcupine (Erethizon dorsatum).
abstract: We measured nitrogen and energy requirements in adult North American porcupines (Erethizon dorsatum) fed three experimental diets differing primarily in crude protein content. Porcupines ingested 497.3-865.4 kJ kg-0.75 d-1, and there was no significant loss of body mass on any dietary treatment. Individuals maintained nitrogen balance on a total nitrogen intake of 389.4 mg N kg-0.75 d-1. The true digestibility of nitrogen was high (88%) but within the range for eutherians. We found metabolic fecal nitrogen to be 0.92 mg N g-1 dry matter intake and endogenous urinary nitrogen to be 223 mg N kg-0.75 d-1. The low value of metabolic fecal nitrogen found for porcupines affects the dry matter intake required for nitrogen balance, and it may allow these animals to exploit nitrogen-poor diets.
authors.affiliation: Département de biologie, Université de Sherbrooke, Québec, Canada.
authors.forename: F
authors.initials: F
authors.lastname: Fournier
authors.forename: D W
authors.initials: DW
authors.lastname: Thomas
mesh_terms: D000818:Animals; D001824:Body Constitution; D004032:Diet; D004044:Dietary Proteins / Q000008:administration & dosage*; D004734:Energy Metabolism; D005260:Female; D008297:Male; D009584:Nitrogen / Q000378:metabolism*; D009751:Nutritional Requirements; D012377:Rodentia / Q000502:physiology*
chemical_list: D004044:Dietary Proteins; D009584:Nitrogen