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1.
  • 1.1. Oxygen consumption at 18°C was 60% of the rate at 22 and 26°C.
  • 2.2. Critical points, where the rate of oxygen consumption changed, were defined at 22°C (2.89 mg DO) and 26°C (3.46 mg DO). Linear regressions were fitted showing that oxygen consumption declined significantly (81.5% ±4.5) below the critical point.
  • 3.3. Oxygen consumption was proportional to weight. Allometric relationships resulted in variable temperature-related coefficients for respiratory dependence on weight, a reflection of the crayfish adaptation towards re-establishment of a new equilibrium state.
  • 4.4. Heart beat rate was lower at 18°C, and highest at the acclimation temperature (22°C). Stress at 26°C was evident.
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2.
  • 1.1. The oxygen consumption by P. californiensis postlarvae (mean wt = 0.38 g) was determined at five different temperatures and four salinities.
  • 2.2. The O2 in each chamber was recorded at 10 min intervals for 1 hr. The time course of oxygen depletion was independent of O2 concentration down to 1.6 mg/l.
  • 3.3. Oxygen consumption increased with temperature from 0.0045 mg/g/min at 19°C, to 0.0142 mg/g/min at 35°C. The thermal coefficient (Q10) indicated a very high sensitivity of the postlarvae to temperature variations at 19–23°C.
  • 4.4. The results show that oxygen consumption significantly depends on temperature (P < 0.001) while salinity has only a marginal effect.
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3.
  • 1.1. The temperature and water relations of Centruroides hentzi females were investigated. At 12 and 72% relative humidity (RH), the lower and upper Lt50 were -4.5 and 43.7°C, and -4.7 and 45.1°C, respectively. When exposed to high temperature stress, survivorship was significantly greater under mesic conditions.
  • 2.2. Cuticular water loss was higher under xeric conditions (12% RH), ranging from 0.061 mg/cm2/hr at 30°C to 0.211 at 41°C.
  • 3.3. Exposure to dry air (0–5% RH) resulted in a significant increase in hemolymph osmolality: from 441 to 688 mOsm over a 5 day period.
  • 4.4. Mean oxygen consumption rates increased from 161.7 mm3/g/hr at 34°C to 541.6 at 44°C. ATPase activity was significantly higher in animals acclimated and tested at 35°C.
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4.
  • 1.1. Mortality was 100% at pH 3.5 over a temperature range of 10–30°C for embryos and nymphs of Caenis diminuta and C. hilaris.
  • 2.2. Hatching success for both species was highest at pH values above 4.5.
  • 3.3. Survival capacities were significantly higher at 20°C over a pH range of 4.0-7.2.
  • 4.4. Oxygen consumption rates increase as a function of increasing temperature and reduced acidity.
  • 5.5. Loss of the nymphal righting response was observed at pH 3.5. This response can be used as a behavioral assay for acid stress.
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5.
  • 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.
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6.
  • 1.1. Developing eggs of whitefish (Coregonus lavaretus L.) and vendace (Coregonus albula L.) were kept at 1–2°C and some eggs taken gradually up to 8°C to provoke mass hatching of embryos.
  • 2.2. Wet weight, dry matter and the contents of lipid, protein and ash were measured in fish during the course of experiment.
  • 3.3. Dry matter content decreased gradually in whitefish eggs from 15.64 to 11.95% during 1 month at 1–2°C, whereas vendace eggs showed only a slight decrease from 16.27 to 15.53%.
  • 4.4. In both species protein content decreased but lipid increased when approaching the natural time of hatching.
  • 5.5. During delayed hatching at low water temperatures protein contributes to catabolism, whereas lipid content decreased only in the later phase of the experiment.
  • 6.6. Larvae starved for 10 days after hatching lost increasing amounts of dry matter (from 26.1 to 50.3% of body weight) and protein (from 18.7 to 45.9% of body weight) as they remained longer in cold water as embryos.
  • 7.7. A correspondence was found between assessment of metabolic utilization of body stores based on chemical analysis of fish body and previous work on oxygen consumption and nitrogen excretion.
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7.
  • 1.1. The ambient temperature of embryos of pipped eggs was reduced from 38 to 28°C for a period of 45 min.
  • 2.2. The blood PCO2 was lower and the blood more alkaline at 28°C than at 38°C.
  • 3.3. At 28°C plasma [HCO3] ] was lower than predicted from the blood buffer line determined in vitro.
  • 4.4. The plasma concentrations of strong ions and lactate were the same at both temperatures.
  • 5.5. After the ambient temperature had been returned to 38°C for a period of 45 min, blood pH was more acidic than before cooling, but there was no difference in blood PCO2.
  • 6.6. The plasma [HCO3] was the same as that at 28°C and plasma [K+] was higher than before cooling.
  • 7.7. The results arc discussed in relation to the factors affecting blood pH in embryos at this stage of development.
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8.
  • 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.
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9.
  • 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.
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10.
  • 1.1. The development of Gallena mellonella is strongly affected by a low temperature of 18°C (the last instar persists for more than one year, instead of about 9 days at 30°C). At 18°C the last instar Galleria mellonella larvae respond to juvenilizing treatment—chilling stress or juvenile hormone analogue—with a very low percentage or no supernumerary moults, respectively.
  • 2.3. Experiments in which larvae subjected to such treatments were transferred from 18°C to 30°C and vice versa showed that for the realization of the larval programme after chilling stress application the higher (30°C) temperature is needed.
  • 3.4. In last instar larvae reared at 18°C there coexist very high juvenile hormone titre and high juvenile hormone esterase activity.
  • 4.5. This phenomenon which is found in both, chilled and unchilled larvae, is discussed.
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11.
12.
  • 1.1. Oxygen uptake attributable to Specific Dynamic Action (SDA) was measured in common carp, Cyprinus carpio L. (63.6–84.0 g) fed on 20, 35 and 50% dietary protein at 0.40 to 1.00% ration levels at 28°C.
  • 2.2. After feeding both SDA magnitude and mean peak oxygen consumption increased directly with dietary protein and ration levels. SDA duration was not significantly related to dietary protein but significantly increased with ration levels.
  • 3.3. SDA coefficients were 8.99, 13.51 and 15.94% with 20, 35 and 50% dietary protein showing a direction relationship to the protein content. The SDA coefficient did not change with ration size.
  • 4.4. SDA models resulting from this work are of great interest for the aquaculturist, as post-feeding oxygen requirements in an intensive fish culture can be predicted where dietary protein and ration levels are known.
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13.
  • 1.1. Measurements of aerobic scope (resting and active oxygen consumption rates) and anaerobic scope (resting and active production of lactate rates in the whole body homogenates) were carried out on the desert skink, Chalcides ocellatus at temperatures between 10 and 40°C.
  • 2.2. The aerobic scope was maximal around the preferred body temperature with a low thermal temperature dependence above the preferred levels.
  • 3.3. During initial stages of forced activity, C. ocellatus employed anaerobic metabolism as its major energy source.
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14.
  • 1.1. The routine rate of oxygen consumption by Peneaus californiensis was determined for the size groups with average weights of 0.26, 2.31 and 10.01 g at five temperatures (19, 23, 27, 31 and 35°C).
  • 2.2. Oxygen consumption (mg O2/g min) was independent of dissolved oxygen (DO) level down to 1.8mg/l, increased with temperature (P < 0.05) from 0.0015mg O2/g min for the preadults at 19°C to 0.0106 mg O2/g min at 35°C for the postlarvae, and was inversely proportional to weight (P < 0.05).
  • 3.3. The thermal coefficient (Q10) indicated a higher sensitivity by preadults to temperature variations.
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15.
  • 1.1. The ventilatory mechanism, gill area, sites of oxygen uptake, oxygen consumption and activity of a crab from south Brazil, Chasmagnathus granulata, were investigated.
  • 2.2. The oxygen uptake seems to be restricted to the gill lamellae.
  • 3.3. The gill area varies with the wet body weight, being relatively higher in smaller animals. There is not a significative reduction of the gill area in relation to species of the infralittoral zone.
  • 4.4. C. granulata presents a mechanism for recirculating the water of its branchial chamber when exposed to atmospheric air.
  • 5.5. The oxygen consumption and activity are reduced when the animals are exposed to atmospheric air. The reduction in the oxygen consumption may be related to the poorly adapted respiratory system, while the decrease in activity may be a mechanism for saving energy during this hypoxic period.
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16.
  • 1.1. Using a high-speed video system operating at 400 frames/sec, the effects of temperature on tail beat frequency, swimming speed and stride length were examined in newly hatched larvae of herring (Clupea harengus L.) and in tadpole larvae of the ascidian Dendrodoa grossularia van Beneden.
  • 2.2. The effect of temperature was linear; the tail beat frequency of 8 mm-long herring larvae increased from 19 Hz at 5.6°C to 37 Hz at 14.9°C (Q10 = 2.04); that of 2 mm-long Dendrodoa larvae increased from 10 Hz at 9.6°C to 23 Hz at 18.1°C (Q10 = 2.52).
  • 3.3. Burst swimming speeds of herring larvae increased from 80 mm/sec at 5°C to 150 mm/sec at 15°C, stride length remaining constant at about 0.5 of the body length for each tail beat.
  • 4.4. More continuous swimming of Dendrodoa increased from 4.0 mm/sec at 10°C to 11.5 mm/sec at 18°C, the stride length increasing from about 0.15 to 0.25.
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17.
  • 1.1. The MO2 for branchial respiration in adult snails increased from 0.24 mmol/l/O2 kg/hr at 18°C to 0.83 mmol/l/O2 kg/hr at 40°C. Q10 values were 2.75 between 35 and 40°C and 1.8 between 18 and 30°C.
  • 2.2. The haemocyanin (31.9 ± 5.8 mg/ml) has a high oxygen affinity (6.28 ± 0.8 at 25°C) with a reversed Bohr effect measured between a pH of 6.80 and 7.95 with gelchromatographed haemolymph, and measured between a pH of 7.34 and 8.10 for native haemolymph.
  • 3.3. Growth rate is optimal between 27 and 30°C whilst at 24°C stunted growth was found.
  • 4.4. At 25°C the same MO2 values were found for aerial and aquatic respiration.
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18.
  • 1.1. In 43 European bison divided into three groups (Group A, 3–8-month-old calves; Group B, 18-month-7-year-old young bison; Group C, 12–24-year-old bison) the rectal, humerus region and abdomen region temperatures were measured.
  • 2.2. The experiments were carried out in winter months, from mid-December to mid-March.
  • 3.3. The mean rectal temperatures changed from 38.55°C in calves to 38.15°C in the oldest bison.
  • 4.4. The mean temperatures of the humerus region changed from 20.69°C in calves to 21.49°C in older bison.
  • 5.5. The mean temperatures of the abdomen region changed from 20.79°C in calves to 22.17°C in older bison (Gr. B).
  • 6.6. The cluster analysis divided the bison into four groups named hot, warm, cool and cold bison.
  • 7.7. Only air temperature measured 2 m above the ground and snow cover influenced the integrated bison temperature. Age, sex and mass as well as some environmental factors had no influence.
  • 8.8. Measurements made 1 to nearly 4hr after a bison's death showed a drop in rectal temperature and mostly increases in temperatures of the humerus and abdomen regions.
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19.
  • 1.1. Changes in the blood and in the rate of oxygen consumption of Japanese eels injected intramuscularly in the head with a lethal dose of typical or atypical Aeromonas salmonicida at 20°C were investigated.
  • 2.2. Eels infected with the bacteria became moribund within 4 to 6 days, and then died within 1 day.
  • 3.3. The O2 consumption rate and blood parameters changed markedly with infections. The responses of hosts to infection by the two kinds of bacteria differed with regard to the following four points: blood pH, plasma Cl, lactic acid, and the numbers of granulocytes and lymphocytes.
  • 4.4. The responses of eels infected with atypical A. salmonicida were larger and more rapid than those of eels infected with typical A. salmonicida.
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20.
  • 1.1. Proteolytic, lipolytic, amylolytic and cellulolytic activities were studied in adults of the phytophagous beetle, Hydromedion sparsutum, indigenous to the sub-Antarctic island of South Georgia.
  • 2.2. Gastric enzyme activities were measured at experimental temperatures of 5–40°C and results were compared with those obtained from two thermophilic insects, Gryllus bimaculatus and Tenebrio molitor.
  • 3.3. Protease and lipase activities in Hydromedion were 10–15 times lower than in Gryllus and Tenebrio.
  • 4.4. In the temperature range of 5–15°C, α-amylase activity from Hydromedion was only slightly lower than that from Gryllus.
  • 5.5. Hydromedion gut homogenates exhibited a distinct cellulolytic activity, even at a low temperature of 5°C.
  • 6.6. Cellulolytic activity in the digestive tract of Hydromedion was confirmed by the evolution of 14CO2 after consumption of labelled cellulose.
  • 7.7. The thermal properties of digestive enzymes agree well with the role of Hydromedion as primary decomposer in its ecosystem.
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