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1.
《Comparative biochemistry and physiology. A, Comparative physiology》1979,62(4):807-812
- 1.1. Filtering rates and oxygen consumption were measured in the field on a wild population of the fresh-water limnetic cladoceran Daphnia ambigua.
- 2.2. Filtering rates increased with increasing body size and were significantly affected by environmental temperature.
- 3.3. Oxygen consumption increased with increasing body size; there was no significant difference among b values determined at different environmental temperatures but bs were highest at low temperatures. decreased progressively at higher temperatures and increased at the highest temperatures.
- 4.4. Temperature significantly affected the rate of oxygen consumption.
- 5.5. Both filtering rates and oxygen consumption evidenced classical translation to the left in cold-acclimatized animals. An environmental temperature near 12°C apparently separates warm- and cold-acclimatization processes.
2.
《Comparative biochemistry and physiology. A, Comparative physiology》1982,71(4):579-584
- 1.1. Evaporative water loss was measured as a function of temperature, season and grouping in the kangaroo rat, Dipodomys panamintinus for a one year period.
- 2.2. Three groups of Panamint kangaroo rats were set up and studied during the various changes in season. The three groups were designated as field, exposed and control. These groups revealed the effects of acclimatization, captive acclimatization and laboratory acclimatization respectively.
- 3.3. There is a highly significant difference in the rate of evaporative water loss in the Field Panamint kangaroo rats during the Fall, Winter and Spring.
- 4.4. In general, the quantity of water loss via evaporation was higher in the female Panamint kangaroo rats.
- 5.5. Water loss via evaporation in the control and exposed groups was least affected by seasonal change.
- 6.6. In comparison to the other two groups, the field male and female Panimint kangaroo rats possessed the highest slope (rate) and mean (quantity) for all seasons.
- 7.7. The combined effect of both grouping and season affects both the rate and quantity of evaporative water loss in the Panamint kangaroo rat.
3.
《Comparative biochemistry and physiology. A, Comparative physiology》1990,95(1):139-144
- 1.1. Common carp (Cyprinus carpio) exposed to experimental temperatures of 12, 18, 24, 30 or 36°C for a 4-week period were used to investigate the effect of temperature acclimation on the frequency of opercular movement (FOM), growth and cytochrome c oxidase (CCO) activity in heart, liver and muscle.
- 2.2. An exponential relationship between FOM and temperature after the first week (1010 =1.76) disappeared after the second week.
- 3.3. The initially high FOM at temperatures of 30 or 36°C and the low FOM at 18 or 12°C changed over 4 weeks to approach the FOM of fish at 24°C.
- 4.4. This change in the relationship of FOM to temperature from highly dependent to independent appeared to be thermal compensation.
- 5.5. Heart and liver CCO activities were significantly affected by temperature, with the lowest activity at the approximate optimum temperature for growth, 24°C.
- 6.6. Highest CCO activities for heart and liver occurred at both the highest and lowest temperatures.
- 7.7. Among the three tissues, heart CCO activity was generally the highest and most affected by acclimation temperature.
- 8.8. Muscle tissue had the lowest CCO activity and was unaffected by temperature.
- 9.9. The high CCO activity at a cold acclimation of temperature 12°C was probably due to thermal compensation and the high activity at 36°C may have been a result of thermal stress.
4.
《Comparative biochemistry and physiology. A, Comparative physiology》1979,62(3):585-592
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- 1.1. Fennecs show marked diurnal variations of body temperature and heart rate.
- 2.2. Basal metabolic rate (0.358 ml/ghr) is 39% lower than predicted by body mass, minimal conductance is reduced for 23%.
- 3.3. Fennecs have a wide thermoneutral zone (23.4–32.0°C) and a low rate of evaporative water loss.
- 4.4. Basal heart rate is considerably reduced. Oxygen pulse increases with decreasing ambient temperature. The higher oxygen demands below thermal neutrality, however, are met primarily by a rise in heart rate.
- 5.5. Newborn fennecs show a metabolic response to cold from the first day of life.
5.
《Comparative biochemistry and physiology. A, Comparative physiology》1980,65(3):305-309
- 1.1. Coatis are chiefly diurnal, showing marked nycthemeral variations of body temperature and oxygen uptake.
- 2.2. The thermoneutral zone extends from 25–33°C; the basal metabolic rate is about 40% below the value predicted from body mass.
- 3.3. Thermoregulation in cold is excellent, partly due to decreasing thermal conductance at falling ambient temperatures.
- 4.4. Exposure to temperatures above 35°C is endured for only short periods.
- 5.5. Basal heart rate is reduced to about 70% of the predicted level. The contribution of heart rate to increased oxygen demands at falling ambient temperatures is rather low.
- 6.6. The measured physiological characteristics of coatis are discussed with regard to the high mobility and the wide distribution range of these procyonids.
6.
《Comparative biochemistry and physiology. A, Comparative physiology》1993,104(2):183-186
- 1.1. Ultradian oscillations in the min and hr range on long-term (24-hr) computerized recordings of heart rate in rainbow trout Oncorhynchus mykiss, acclimated to 5, 10 and 15°C water temperature, were investigated. Eight-hour duration time series derived from the heart rate recordings were analysed for their harmonic content in the ultradian band by spectral analysis.
- 2.2. A significant ultradian rhythm at around 0.011 cycles/min (approximately 91-min period) was detected in the power spectral density functions of all the 8-hr duration time series derived from the heart rate recordings at the three experimental water temperatures.
- 3.3. The spectral power of the ultradian oscillation detected in heart rate of trout was found to increase significantly with increasing temperature.
- 4.4. The possible endogenous origin of the ultradian rhythm detected in heart rate of Oncorhynchus mykiss is discussed.
7.
《Comparative biochemistry and physiology. A, Comparative physiology》1992,101(1):93-98
- 1.1. The role of the visceral nerve in mediating the changes in heart rate associated with different behavioral patterns was investigated in Megalobulimus sanctipauli.
- 2.2. The results of acute and chronic denervation experiments indicate that the visceral nerve has no excitatory or inhibitory tonic action on the heart of snails retracted into the shell, nor does it account for the increase in heart rate associated with the locomotion and feeding behaviors.
- 3.3. These changes in heart rate are, probably, indirect effects of increased activity such as an increase in venous return.
- 4.4. The visceral nerve is responsible for approximately 3/4 of the increase in heart rate associated with the first minute of extrusion.
- 5.5. The small increase in heart rate observed in denervated animals is probably caused by an increase in venous return generated by muscle activity that forces the head and food out of the shell.
8.
- 1.1. Seasonal acclimatization effects on oxygen consumption, body temperature, and body weight were evaluated in three different experimental groups of Dipodomys panamintinus.
- 2.2. Body weights of wild field as well as captive animals housed in outdoor sand cages were maximum in winter and lowest in summer for both sexes.
- 3.3. Mean oxygen consumption was maximum in winter and lowest during spring in both sexes of the wild field and captive exposed groups.
- 4.4. Neither weight nor oxygen consumption of indoor control animals varied with the seasons.
- 5.5. No significant differences in body temperatures were observed during either the fall or winter seasons.
9.
《Comparative biochemistry and physiology. A, Comparative physiology》1980,65(1):147-150
- 1.1. The haematology of tame racing pigeons (Columba livia) and wild guinea-fowl (Numida meéagris) was investigated immediately after transportation to the laboratory and during subsequent acclimatization.
- 2.2. Significant changes were observed in many of the parameters studied and both experimental groups showed similar variations.
- 3.3. The results are discussed in relation to the factors which may be responsible for incorrect haematological values being obtained in birds.
10.
《Comparative biochemistry and physiology. A, Comparative physiology》1991,98(4):963-968
- 1.1. The heart rate and motor activity of lizards (Gallotia galloti) maintained in a light-dark cycle (12:12 hr) and with changing cyclic temperature were recorded. Both variables showed a circadian pattern, motor activity variations leading heart rate by approximately 110 min.
- 2.2. Results from cross spectral analysis showed that heart rate was highly correlated with temperature and both variables were changing practically in phase. However, motor activity and temperature were less correlated and in this case motor activity led temperature by approximately 100 min.
- 3.3. In the ultradian range, two periodicities could be distinguished in the power spectra of motor activity and heart rate variations during the day: one between 0.019 and 3.9 × 10−3 cycles/min (central peak around 85 min period) and another, of lower power, between 0.05 and 0.02 cycles/min (central peak around 34 min period). During the night, only the heart rate showed both periodicities but with a lower amplitude.
- 4.4. The presence of ultradian oscillations in heart rate during the night suggested that they do not depend on motor activity which was almost absent during that daily period.
- 5.5. Motor activity and heart rate were also highly correlated in the ultradian range, motor activity leading heart rate by around 5 min at the 85 min main peak.
11.
《Comparative biochemistry and physiology. A, Comparative physiology》1980,65(3):259-263
- 1.1. Cardiac frequency patterns of Callincctes sapidus Rathbun were used to evaluate potential thermal stress after exposure to 5°C increases over a range of acclimation temperatures from 5° to 30°C.
- 2.2. An acclimated rate-temperature curve (R-T curve), acute R-T curves of the stabilized rates at the increased temperatures and Q10 temperature coefficients were used to assess the significance of the changes in rate frequency.
- 3.3. The acclimated R-T curve showed that blue crabs go through a series of seasonal adaptation types characterized by a plateau of perfect adaptation for both cold and warm adapted organisms. Paradoxical adaptation occurred between the transition from cold to warm acclimation temperatures.
- 4.4. The acute R-T curves showed that cardiac frequency was highly responsive to a 5°C increase when the organisms were acclimated to low temperatures.
- 5.5. The Q10's of the acute R-T curves at the warm acclimation temperatures approximated those values derived for the acclimated R-T curve.
- 6.6. This suggests that the temperature increase had a negligible effect on the warm adapted crabs, that is, little or no thermal stress occurred.
12.
《Comparative biochemistry and physiology. C: Comparative pharmacology》1979,62(2):275-278
- 1.1. Heart rate-temperature relationships were determined on unanaesthetized, unrestrained eels acclimated to 15°C and 25°C.
- 2.2. Heart rate in eels with intact vagal tonus exhibited a nearly complete temperature compensation. The degree of compensation was considerably reduced by blocking the vagus function with benzetimide.
- 3.3. The difference in the sensitivity of heart rate to temperature change induced by temperature acclimation was significantly decreased after benzetimide-treatment.
- 4.4. The inhibitory vagal tonus was significantly higher in warm-acclimated than in cold-acclimated eels.
- 5.5. It is concluded that adaptation of heart rate to temperature is mediated by the parasympathetic system to a great extent.
13.
《Comparative biochemistry and physiology. A, Comparative physiology》1984,77(3):339-344
- 1.1. The cardiovascular physiology of adult Carcinus maenas (L.) emerging into air has been investigated at three different air temperatures.
- 2.2. Transition from seawater to air or vice versa triggered transient increases in cardiac and locomotor activity.
- 3.3. However, crabs became inactive 5–10 min after emerging from seawater (15°C) into air at the same temperature (15°C) or at lower temperatures (12–13°C) and heart rate fell.
- 4.4. At higher air temperatures (18–20°C) heart rate rose but to a lesser extent than predicted from aquatic Q10 heart-rate values.
- 5.5. Crabs were again quiescent in aerial conditions.
- 6.6. Mean arterial oxygen tension (Pao2) was ~ 74 mmHg in submerged crabs but fell to ~ 38 mmHg in air while mean arterial carbon dioxide tension (Pao2) increased from 1 to 4 mmHg resulting in respiratory acidosis.
- 7.7. A model of gill function is proposed to explain the development of internal hypoxia in air.
- 8.8. The results are discussed in relation to the distribution of adult and juvenile C. maenas in situ.
14.
《Journal of thermal biology》2006,31(6):501-505
- 1.Establishing if and how organisms modulate temperature changes is an important component of understanding their thermal biology.
- 2.We used temperature-sensitive radio-transmitters to monitor heating and cooling rates between 5 and 35 °C of four Crotalus adamanteus in the laboratory.
- 3.We found no difference between heating and cooling rates in C. adamanteus. Additionally, rates of temperature change mirrored those of a biophysical model, further suggesting a lack of physiological thermoregulation.
- 4.Our findings contrast previously published studies that demonstrate active temperature control of similarly sized reptiles and demonstrate a need for more investigations of physiological thermoregulation in reptiles.
15.
《Comparative biochemistry and physiology. A, Comparative physiology》1979,62(3):661-667
- 1.1. The exponent (b) relating metabolic rate to dry weight in excised gills of Tagelus plebeius is not maintained constant throughout the seasons or upon acute exposure to temperatures of 9–34°C.
- 2.2. Acclimation (11–29°C) and test (9–34°C) temperatures have a significant effect (α = 0.01) on the mean rate of oxygen uptake by the gills.
- 3.3. Positive seasonal thermal acclimation is observed up to acclimation temperatures of 19.5–20°C, which is also the temperature of minimum respiratory response to all acute test temperatures.
- 4.4. Regions of thermal metabolic insensitivity are seen over small acute temperature ranges near the acclimation temperatures.
16.
《Comparative biochemistry and physiology. A, Comparative physiology》1979,62(2):283-294
- 1.1. The effects of temperature, salinity and declining O2 on the heart rates of nine species representing four animal phyla have been investigated in relation to other respiratory paramters.
- 2.2. The effect of temperature on heart rate is at least the same as, and often greater than, the effect of temperature on O2 consumption, thus providing no evidence that adaptations of the cardiovascular system facilitate metabolic compensations for a temperature change.
- 3.3. Responses to reduced acclimation salinity are very diverse among the various species, permitting no general conclusions about the role of the cardiovascular system in adaptations to estuarine habitats.
- 4.4. At low PO2 the typical response is bradycardia, which is especially notable in species with a high capacity for anaerobic metabolism. Compensatory tachycardia, the expected response in vertebrates, is very rare in other animal groups.
- 5.5. Estimates of cardiac output from these data generally agree with those obtained according to the Fick principle from blood gas tensions.
- 6.6. The estimates of cardiac output are evaluated in terms of body size, temperature and the design of cardiac muscle, which is fundamentally different in various animal phyla.
17.
- 1.1. Adult Emerita talpoida were subjected to 25 temperature-salinity combinations within the range of 5–35°C and 15–65‰.
- 2.2. E. talpoida tolerated 15–65‰ salinity at 20°C and below.
- 3.3. Optimum salinity for survival at stressful temperatures was 40‰.
- 4.4. Crabs transferred directly from one salinity to another experienced changes in osmoconcentration toward that of the new salinity.
- 5.5. Temperature modified the rate of change toward the experimental salinity. Q values averaged 1.2.
18.
《Comparative biochemistry and physiology. A, Comparative physiology》1979,62(4):885-888
- 1.1. Heart rates of five unrestrained white-tailed deer fawns were monitored for 24 hr periods at intervals between birth and weaning at about 100 day of age (25 kg body weight).
- 2.2. Mean heart rates during lying-resting activity declined exponentially with body weight to about 54% of the neonatal rate.
- 3.3. Increases in the mean heart rate with spontaneous changes in activity from lying to lying-ruminating, standing, foraging, walking and running were related curvilinearly to body weight.
- 4.4. Heart rates for these same activities were higher when fawns were alarmed or excited.
19.
《Comparative biochemistry and physiology. A, Comparative physiology》1991,98(1):169-174
- 1.1. The influence of temperature (14,19, 24°C), salinity (26,32, 38,44%.) and food type (artificial diets: Fryfood, Mytilus, Soya, Yeast, Spirulina) on the respiratory rate of Tisbe holothuriae has been studied.
- 2.2. Oxygen consumption decreased with decreasing temperature, but with a greater rate at supra- or subnormal salinities.
- 3.3. Multiple-regression analysis showed the quadratic effect of temperature and the linear effect of salinity to be the more important factors affecting respiration.
- 4.4. The food type also seems to exert an important effect on oxygen consumption.
- 5.5. A significant lowering of respiration was observed for all food tested when the animals were starved.
20.
《Comparative biochemistry and physiology. A, Comparative physiology》1987,86(2):187-199
- 1.1. Both the small riparian skink Sphenomorphus quoyii and its completely terrestrial relative Ctenotus robustus respond to forced submergence with instantaneous bradycardia.
- 2.2. The strength of the bradycardia was affected by water temperature and fear. Dives into hot (30°C) water produced weak and erratic bradycardia compared to dives into cold (19.5°C) water. For S. quoyii the strongest bradycardia occurred when submergence took place in water at a lower temperature than the pre-dive body temperature.
- 3.3. Upon emergence both species of skink exhibited elevated heart rates and breathing rates while heating from 19.5 to 30°C, compared to heating at rest. The increased heart and breathing rates probably act to replenish depleted oxygen stores and remove any lactate. Increased heart and ventilation rates are not indicators of physiological thermoregulation in this case.
- 4.4. Both lizard species exhibited higher heart rates and ventilation frequencies during heating than cooling.
- 5.5. Compared to its terrestrial relative, S. quoyii does not appear to possess any major thermoregulatory, ventilatory or cardiovascular adaptations to diving. However, very small reptiles may be generally preadapted to use the water to avoid predators.