title: Measurement of maximum oxygen consumption in Guinea fowl Numida meleagris indicates that birds and mammals display a similar diversity of aerobic scopes during running.
abstract: Judgement of exercise performance in birds has been hampered by a paucity of data on maximal aerobic capacity. We measured the maximal rate of oxygen consumption (Vo2,max) in running guinea fowl Numida meleagris, a bird that has been used in several previous studies of avian running. Mean Vo2,max during level treadmill running was 97.5+/-3.7 mL O(2) kg(-1) min(-1) (mean+/-SEM, N=5). Vo2,max was on average 6% higher when the birds ran uphill compared with the value during level running (paired t-test, P=0.041, N=5). The mean basal rate of oxygen consumption (Vo2,bmr) of the same individuals was 7.9+/-0.5 mL O(2) kg(-1) min(-1). Mean factorial aerobic scope based on individually measured values of Vo2,max and Vo2,bmr was 13.2+/-0.6 (mean+/-SEM, N=5). This value was considerably lower than the factorial aerobic scope previously measured during running in Rhea americana, a large flightless ratite. The difference in factorial scope between these two running birds likely reflects the effects of body size as well as size-independent differences in the ability to deliver and use oxygen. These data confirm a previous prediction that birds have a diversity of factorial aerobic scopes similar to that exhibited by mammals.
authors.affiliation: Department of Biology, Northeastern University, Boston, MA, 02115, USA. bgydje@leeds.ac.uk
authors.forename: David J
authors.initials: DJ
authors.lastname: Ellerby
authors.forename: MaryEllen
authors.initials: M
authors.lastname: Cleary
authors.forename: Richard L
authors.initials: RL
authors.lastname: Marsh
authors.forename: Cindy I
authors.initials: CI
authors.lastname: Buchanan
mesh_terms: D000818:Animals; D001717:Birds / Q000502:physiology*; D005080:Exercise Test; D019344:Lactic Acid / Q000097:blood; D010101:Oxygen Consumption / Q000502:physiology*; D012420:Running / Q000502:physiology*
chemical_list: D019344:Lactic Acid