The relationship between rate of oxygen consumption, heart rate and thermal conductance of the dik-dik antelope (Rhynchotragus kirkii) at various ambient temperatures

1982 ◽  
Vol 73 (1) ◽  
pp. 21-24 ◽  
Author(s):  
J.M.Z Kamau ◽  
G.M.O Maloiy
2001 ◽  
Vol 204 (12) ◽  
pp. 2133-2144 ◽  
Author(s):  
G. Froget ◽  
P. J. Butler ◽  
Y. Handrich ◽  
A. J. Woakes

SUMMARY The use of heart rate to estimate field metabolic rate has become a more widely used technique. However, this method also has some limitations, among which is the possible impact that several variables such as sex, body condition (i.e. body fat stores) and/or inactivity might have on the relationship between heart rate and rate of oxygen consumption. In the present study, we investigate the extent to which body condition can affect the use of heart rate as an indicator of the rate of oxygen consumption. Twenty-two breeding king penguins (Aptenodytes patagonicus) were exercised on a variable-speed treadmill. These birds were allocated to four groups according to their sex and whether or not they had been fasting. Linear regression equations were used to describe the relationship between heart rate and the rate of oxygen consumption for each group. There were significant differences between the regression equations for the four groups. Good relationships were obtained between resting and active oxygen pulses and an index of the body condition of the birds. Validation experiments on six courting king penguins showed that the use of a combination of resting oxygen pulse and active oxygen pulse gave the best estimate of the rate of oxygen consumption V̇O2. The mean percentage error between predicted and measured V̇O2 was only +0.81% for the six birds. We conclude that heart rate can be used to estimate rate of oxygen consumption in free-ranging king penguins even over a small time scale (30min). However, (i) the type of activity of the bird must be known and (ii) the body condition of the bird must be accurately determined. More investigations on the impact of fasting and/or inactivity on this relationship are required to refine these estimates further.


2002 ◽  
Vol 205 (16) ◽  
pp. 2511-2517 ◽  
Author(s):  
G. Froget ◽  
Y. Handrich ◽  
Y. Le Maho ◽  
J.-L. Rouanet ◽  
A. J. Woakes ◽  
...  

SUMMARY This study investigated whether exposure to low ambient temperature could be used as an alternative to exercise for calibrating heart rate (fH)against rate of oxygen consumption(V̇O2) for subsequent use of fH to estimate V̇O2 in free-ranging animals. Using the relationship between the oxygen pulse (OP, the amount of oxygen used per heart beat) and an index of body condition (or nutritional index, NI), a relationship between fH and V̇O2 was established for resting king penguins exposed to a variety of environmental temperatures. Although there was a small but significant increase in the OP above and below the lower critical temperature (-4.9°C), there was no difference in the relationship obtained between the OP and body condition (NI)obtained above or below the lower critical temperature. These results were then compared with those obtained in a previous study in which the relationship between fH and V̇O2 had been established for king penguins during steady-state exercise. The relationship between OP and NI in the present study was not significantly different from the relationship between resting OP and NI in the previous study. However, the relationship was different from that between active OP and NI. We conclude that, at least for king penguins, although thermoregulation does not affect the relationship between resting OP and NI, temperature cannot be used as an alternative to exercise for calibrating fH against V̇O2 for subsequent use of fH to estimate V̇O2 in free-ranging animals.


2002 ◽  
Vol 205 (21) ◽  
pp. 3347-3356 ◽  
Author(s):  
S. Ward ◽  
C. M. Bishop ◽  
A. J. Woakes ◽  
P. J. Butler

SUMMARYWe tested the hypotheses that the relationship between heart rate(fH) and the rate of oxygen consumption(V̇O2) differs between walking and flying in geese and that fH and V̇O2 have a U-shaped relationship with flight speed. We trained barnacle geese Branta leucopsis (mean mass 2.1 kg) and bar-headed geese Anser indicus(mean mass 2.6 kg) to walk inside a respirometer on a treadmill and to fly in a wind tunnel with a respirometry mask at a range of speeds. We measured fH and V̇O2simultaneously during walking on the treadmill in five individuals of each species and in one bar-headed goose and four barnacle geese during flight in the wind tunnel. The relationships between fH and V̇O2 were significantly different between flying and walking. V̇O2 was higher,and the increment in V̇O2 for a given increase in fH was greater, for flying than for walking geese. The relationship between fH and V̇O2 of free-living barnacle geese during their natural migratory flights must differ from that measured in the wind tunnel, since the fH of wild migratory birds corresponds to values of V̇O2 that are unrealistically low when using the calibration relationship for our captive birds. Neither fH nor V̇O2 varied with flight velocity across the range of speeds over which the geese would fly sustainably.


2001 ◽  
Vol 204 (4) ◽  
pp. 673-684 ◽  
Author(s):  
J.A. Green ◽  
P.J. Butler ◽  
A.J. Woakes ◽  
I.L. Boyd ◽  
R.L. Holder

Twenty-four macaroni penguins (Eudyptes chrysolophus) from three groups, breeding males (N=9), breeding females (N=9) and moulting females (N=6), were exercised on a variable-speed treadmill. Heart rate (fH) and mass-specific rate of oxygen consumption (sVO2) were recorded from the animals, and both fh and sVO2 were found to increase linearly with increasing treadmill speed. A linear regression equation described the relationship between fh and sVO2 for each individual. There were no significant differences in these regressions between breeding and moulting females. There were significant differences in these relationships between all females and breeding males. fH and s VO2 were recorded from five of these animals for a total of 24 h. When fh was used to predict sVO2 for the 24 h period using the derived regressions, the estimate was not significantly different from the measured values, with an average error of −2.1 %. When fh was used to predict sVO2 for the 5 min intervals used for the calibration in all 24 birds, the estimate was not significantly different from the observed values, and the average error was only +0.47 %. Since the fH/sVO2 relationship was the same during periods of the annual cycle when the animals were inactive/fasting and active/foraging, it seems reasonable that, as long as sex differences are taken into account, fh can be used to predict the metabolic rates of free-ranging macaroni penguins all year round.


2017 ◽  
Vol 12 (4) ◽  
pp. 504-513 ◽  
Author(s):  
Charles-Mathieu Lachaume ◽  
François Trudeau ◽  
Jean Lemoyne

The purpose of this study was to investigate the energy expenditure and heart rate responses elicited in elite male midget ice hockey players during small-sided games. Nine players (aged 15.89 ± 0.33 years) participated in the study. Maximal progressive treadmill testing in the laboratory measured the relationship of oxygen consumption ([Formula: see text]) to heart rate before on-ice assessments of heart rate during six different small-sided games: 1v1, 2v2, 2v2 with support player, 3v3 with support player, 3v3 with transitions, and 4v4 with two support players. Heart rate was recorded continuously in each game. 3v3 T small-sided game was the most intense for all four intensity markers. All six small-sided games reached 89% HRmax or more with heart rate peaks in active effort repetition. These findings demonstrate that such small-sided games are considered as high intensity games and are an effective training method for ice hockey players.


2020 ◽  
Vol 1 (1) ◽  
pp. 72-9
Author(s):  
Alfan Mahdi Nugroho ◽  
Yusmein Uyun ◽  
Annemarie Chrysantia Melati

Analgesia epidural telah diperkenalkan secara rutin sebagai salah satu modalitas analgesia pada proses persalinan sejak lama. Hubungan antara analgesia epidural persalinan dengan demam intrapartum pada maternal sudah disebutkan pada beberapa literatur. Demam didefinisikan sebagai peningkatan suhu tubuh lebih dari 38 oC yang didapat dari dua kali pemeriksaan. Beberapa teori yang disebutkan antara lain perubahan termoregulasi, infeksi pada ibu-janin dan inflamasi non-infeksi yang dimediasi oleh sitokin proinflamasi. Namun demikian berbagai mekanisme analgesia epidural dapat menyebabkan demam masih terus diteliti. Identifikasi demam pada ibu saat persalinan merupakan hal yang penting untuk dilakukan karena memiliki konsekuensi klinis pada ibu dan neonatus. Pada ibu ditemukan suhu yang meningkat dikaitkan dengan peningkatan denyut jantung ibu, curah jantung, konsumsi oksigen, dan produksi katekolamin. Sedangkan pada janin demam intrapartum dapat menyebabkan sepsis, perubahan skor APGAR, peningkatan kebutuhan bantuan napas dan kejadian kejang. Efek demam pada ibu dan janin masih terus dipelajari, sehingga suatu saat didapatkan cara pencegahan yang paling baik yang pada akhirnya menghindarkan keraguan untuk melakukan analgesia persalinan.   Fever during labour epidural analgesia Abstract Epidural analgesia has been routinely introduced as one of the analgesia modalities during labour. Literature has mentioned the relationship between epidural analgesia and intrapartum fever among mothers. Fever is defined as increased temperature above 38 oC in more than two measurements. Several theories have been proposed, inculing thermoregulation changes, mother-fetal infection, and non-infectious inflammation mediated by proinflammatory cytokines. However, these mechanisms have been continued to evolve. Fever identification in pregnant women is essential to recognize clinical consequences to both mothers and neonates. Increased temperature in mothers is associated with increased heart rate, cardiac output, oxygen consumption, and catecholamines production. Meanwhile, in neonates intrapartum fever is related to sepsis, APGAR score changes, the need of respiratory support and incidence of neonatal seizure. Therefore, these consequences are extensively studied in order to determine the appropriate prevention.


1968 ◽  
Vol 49 (3) ◽  
pp. 565-582
Author(s):  
G. M. HUGHES ◽  
SHUN-ICHI UMEZAWA

1. The usefulness of a bottom-living fish, the dragonet (Callionymus lyra), in experiments on fish respiration is described. The position and nature of its opercular opening made it possible to determine directly the volume of water pumped over the gills and the PO2 of the mixed expired water. The normal ventilation volume for a 100 g. fish was about 30 c.c./min. 2. The relationship between cardiac and respiratory rhythms was investigated and showed a variety of ratios. The heart usually beats more than once during each respiratory cycle. Individual variations in the coupling between these rhythms was common and close couplings were observed in the absence of anaesthetic and at normal PO2s. 3. Changes in minute volume produced by altering the hydrostatic pressure across the respiratory system did not affect the heart rate. Percentage utilization fell at higher flow rates. Changes in flow per cm. of water pressure gradient was less with negative gradients than when the static pressure on the mouth side exceeded that in the opercular collecting chamber. 4. Oxygen consumption of the fish is directly related to the ambient PO2 over a wide range (30-120 mm. Hg). Sudden lowering of the PO2 in the inspired water leads to compensatory responses in which the minute volume is maintained or increased as a result of a rise in stroke volume and lowered respiratory frequency: there is also a marked bradycardia. During recovery the increased oxygen consumption of the fish resulted from a rise in utilization rather than a change in the respiratory rate or ventilation volume. 5. Analysis of the time course of the changes in heart rate and ventilation volume in experiments in which PO2 was changed supports the view that the receptors mediating bradycardia occur on the gills and respond directly to the change in PO2 rather than to the secondary increase in flow produced by the hypoxia.


1983 ◽  
Vol 104 (1) ◽  
pp. 193-201 ◽  
Author(s):  
B. Grubb ◽  
D. D. Jorgensen ◽  
M. Conner

Cardiovascular variables were studied as a function of oxygen consumption in the emu, a large, flightless ratite bird well suited to treadmill exercise. At the highest level of exercise, the birds' rate of oxygen consumption (VO2) was approximately 11.4 times the resting level (4.2 ml kg-1 min-1). Cardiac output was linearly related to VO2, increasing 9.5 ml for each 1 ml increase in oxygen consumption. The increase in cardiac output is similar to that in other birds, but appears to be larger than in mammals. The venous oxygen content dropped during exercise, thus increasing the arteriovenous oxygen content difference. At the highest levels of exercise, heart rate showed a 3.9-fold increase over the resting rate (45.8 beats min-1). The mean resting specific stroke volume was 1.5 ml per kg body mass, which is larger than shown by most mammals. However, birds have larger hearts relative to body mass than do mammals, and stroke volume expressed per gram of heart (0.18 ml g-1) is similar to that for mammals. Stroke volume showed a 1.8-fold increase as a result of exercise in the emus, but a change in heart rate plays a greater role in increasing cardiac output during exercise.


Author(s):  
R. C. Newell ◽  
H. R. Northcroft

The rate of cirral beat of Balanus balanoides is related to the logarithm of the body weight as an exponential function. In any one animal, there is little effect of temperature on cirral activity between 7·5° and 10° C. Between 10° and 20° C, however, there is a rapid increase in cirral beat with temperature followed by a fall at temperatures above 20° C.Balanus balanoides exhibits a fast, medium and zero rate of oxygen consumption. These rates of oxygen consumption correspond with (a) normal cirral beating, (b) ‘testing’ activity with no cirral movement, and (c) with the closure of the mantle cavity. Both of the possible levels of oxygen uptake are related to the logarithm of the body weight in a logarithmic fashion over the temperature range 7·5°–22·5° C. Temperature affects the two rates of oxygen consumption differently. In the slower rate (rate B) there is an increase in the rate of oxygen consumption between 7·5° and 14° C but there is no significant increase in the rate of oxygen consumption between 14° and 22·5 C°.


Sign in / Sign up

Export Citation Format

Share Document