Biomaterial Database

Cardiac output of dogs exercising in the heat. 1984

L W Chapman, and M A Baker

We measured cardiac output and central blood temperature in five large dogs (27 kg mean body wt) running at 7.5 km/h for 30 min at two work loads and at low and high ambient temperature (Ta). Each animal ran on a level treadmill (O2 cost about 4 times that of resting) at 25 and 35 degrees C Ta and at a 20% slope (O2 cost about 10 times that of resting) at 25 and 35 degrees C Ta. Cardiac output (CO) was the same at 15 and 30 min of exercise at both work loads and both TaS. CO was higher at 35 degrees C Ta at both work loads. Blood temperature rose 0.6 degrees C during exercise on the level treadmill at 25 degrees C and stabilized after the 15th min of exercise. On the level treadmill at 35 degrees C, blood temperature increased by 1.9 degrees C after 30 min. During 30 min of running at 20% slope, blood temperature increased by 3.2 degrees C at 25 degrees C and by 4.6 degrees C at 35 degrees C. At these work loads the dog is able to increase CO during exercise in the heat. This response is similar to that of humans doing moderate exercise in the heat but is in contrast to that of humans doing heavy exercise in the heat, in whom CO shows a drop or no change compared with cool conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

UI	MeSH Term	Description	Entries
D008297	Male		Males
D010101	Oxygen Consumption	The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)	Consumption, Oxygen,Consumptions, Oxygen,Oxygen Consumptions
D001831	Body Temperature	The measure of the level of heat of a human or animal.	Organ Temperature,Body Temperatures,Organ Temperatures,Temperature, Body,Temperature, Organ,Temperatures, Body,Temperatures, Organ
D001833	Body Temperature Regulation	The processes of heating and cooling that an organism uses to control its temperature.	Heat Loss,Thermoregulation,Regulation, Body Temperature,Temperature Regulation, Body,Body Temperature Regulations,Heat Losses,Loss, Heat,Losses, Heat,Regulations, Body Temperature,Temperature Regulations, Body,Thermoregulations
D002302	Cardiac Output	The volume of BLOOD passing through the HEART per unit of time. It is usually expressed as liters (volume) per minute so as not to be confused with STROKE VOLUME (volume per beat).	Cardiac Outputs,Output, Cardiac,Outputs, Cardiac
D003080	Cold Temperature	An absence of warmth or heat or a temperature notably below an accustomed norm.	Cold,Cold Temperatures,Temperature, Cold,Temperatures, Cold
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
D005082	Physical Exertion	Expenditure of energy during PHYSICAL ACTIVITY. Intensity of exertion may be measured by rate of OXYGEN CONSUMPTION; HEAT produced, or HEART RATE. Perceived exertion, a psychological measure of exertion, is included.	Physical Effort,Effort, Physical,Efforts, Physical,Exertion, Physical,Exertions, Physical,Physical Efforts,Physical Exertions
D005260	Female		Females
D006358	Hot Temperature	Presence of warmth or heat or a temperature notably higher than an accustomed norm.	Heat,Hot Temperatures,Temperature, Hot,Temperatures, Hot