MALOIY, G.M.O.; RUGANGAZI, B.M.; ROWE*, M.F.; Institute of Animal Physiology and Biotechnology Research, Nairobi; Institute of Animal Physiology and Biotechnology Research, Nairobi; University of New Orleans: Heart Rate and Energy Expenditure at Rest and Exercise in the Domestic Donkey and One Humped Camel
Both the domestic donkey and one-humped camel are of great economic value due to their use as transport and pack animals. The present study sought to determine whether a suitable relationship exists, in the donkey and camel, between heart rate (beats/min) and energy expenditure (W/kg) during rest and exercise. Energy expenditure at rest and exercise was measured on 3 donkeys (mean body mass 170 kg) and 2 camels (mean body mass 240 kg) by open system at speeds between 0 and 2.2 m/s on a level motor driven treadmill with an ambient room temperature of 22�C. Stride length, stride frequency, heart rate and energy expenditure all increased linearly with increasing speed in both donkeys and camels. Cost of transport (J/kg m) for the camel was lower than that of the donkey throughout the range of speeds. Minimal cost of transport during walking for the donkey (1.9 J/kg m) and camel (1.2 J/kg m) occurred at 1.11 m/s and 1.67 m/s respectively. We found close relationships between rates of energy expenditure and heart rate (R>0.96), thus heart rate can be useful indicator of energy expenditure in both donkeys and camels. Research supported by Leverhulm Trust Funds London and NORAD KEN 046 Project.