Temperature and salinity tolerance of the mole crab,Emerita talpoida (Say) (Crustacea,Anomura)

• 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.

     

Entomopathogenic fungal infection (Deuteromycotina: Hyphomycetes) affects water relations of the german cockroach,Blattella germanica (L.) (Dictyoptera: Blattellidae)

• 1.1. The total body water, lipid content, and cuticular permeability of fungus infected and uninfected German cockroaches, Blattella germanica, were examined.
• 2.2. Infected adult cockroaches weighed less and had significantly more body water than did uninfected specimens of the same size.
• 3.3. Uninfected medium-size nymphs weighed significantly more than infected nymphs, but there was no difference in body size between infected and uninfected small nymphs.
• 4.4. Cuticular permeability and lipid content of infected and uninfected cockroaches was not significantly different.
• 5.5. Sequestering of water by the fungal cells is discussed as a possible factor in the pathology of this fungal parasite.

     

Lipid and carbohydrate metabolism of the intertidal crab Chasmagnathus granulata dana, 1851 (Crustacea: Decapoda) during emersion

• 1.1. Lipid, glucose and glycogen concentrations were measured in different tissues of the crab Chasmagnathus granulata during emersion.
• 2.2. After 6 hr of emersion no reduction in the total amount of carbohydrates was found to occur, suggesting that a general metabolic arrest was taking place.
• 3.3. A transitory increase in haemolymphatic glucose and lipid levels was observed. Possible causes are therefore discussed in relation to changes in the flux of substrates for energy production.
• 4.4. The mobilization of carbohydrates and lipids to the gills, observed only during summer, may be concerned with energy supplying for ionic regulation.

     

A comparative study of glucose metabolism between the camel (Camelus dromedarius) and the sheep (Ovis aries)

• 1.1. Glucose entry rate was measured in two camels (Camelus dromedarius) and two sheep (Ovis wies) in the fed state and also after 72 hr of fasting.
• 2.2. Plasma glucose concentration in the fed camels (129 mg/100 ml) was considerably higher than that of the fed sheep (63 mg/100 ml).
• 3.3. The mean glucose entry rate in the fed camels (1.67mg/min per kg body wt) was very similar to the sheep (1.79 mg/min per kg body wt).
• 4.4. When the results were expressed as a function of the metabolic body size, the entry rates in the camel were 1.5 times greater than that of the sheep.
• 5.5. The relationship between glucose entry rate and plasma glucose concentration in different mammalian species is discussed.

     

Contribution of aerobic and anaerobic scope to the total metabolic scope of the desert skink,Chalcides ocellatus (Forskal)

• 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.

     

O2-binding by the blood of the landhopper,Arcitalitrus dorrieni (Hunt) (Crustacea: Amphipoda)

• 1.1. The O₂-binding characteristics of the blood of the euterrestrial amphipod (landhopper) Arcitalitrus dorrieni have been studied.
• 2.2. The blood exhibited a low O₂ affinity, with a p₅₀ (at pH = 7.8) of 21.4 torr (10°C). Affinity decreased with an increase in temperature at constant pH (ΔH = − 79.4kJ/mol) but the Bohr factor (ΔlogP₅₀/Δ pH = −0.67) was unaffected.
• 3.3. The O₂-carrying capacity of the blood was moderate (1.51 ml/100 ml)
• 4.4. The results support the hypothesis that the blood of terrestrial amphipods is characterized by having a low affinity pigment.

     

Respiration in the eastern water dragon,Physignathus lesueurii (agamidae)

• 1.1. Some aspects of the gas exchange system of a diving lizard, Physignathus lesuewii were studied.
• 2.2. Breathing patterns were analysed.
• 3.3. Breathing rate increases logarithmically with temperature and Q₁₀ = 1.8. LogBR = −0.237 + 0.0256 T.
• 4.4. Gas tensions in lung air and arterial and venous blood were measured. Arterial pH declines with increasing temperature.
• 5.5. Temperature has a marked effect on oxygen affinity of the blood (ΔH = −10.1 kcal mol⁻). A Bohr effect was also noted.
• 6.6. CO₂ equilibrium curves were drawn.
• 7.7. The results are considered with a view to anticipating the efficiency of the gas exchange system of this species under conditions of variable temperature and during diving.

     

Respiration and energetics in west indian gorgonacea (Anthozoa,octocorallia)

• 1.1. The rates of oxygen consumption of five species of Gorgonacea were determined and their daily energy requirements for metabolism were estimated.
• 2.2. Oxygen consumption rates varied between 0.15 and 0.76 mg O₂ g organic matter⁻¹ hr⁻¹.
• 3.3. Daily energy requirements varied between 13 and 66 cal g organic matter⁻¹ d⁻¹.
• 4.4. Energy costs for maintenance were somewhat lower than in other reef-dwelling Anthozoa.

     

The influence of anaerobiosis on the levels of adenosine nucleotides and some glycolytic metabolites in tubifex sp. (annelida,oligochaeta)

• 1.1. In Tubifex sp. the amounts of ATP, ADP and AMP, and of glucose, glucose-1-P, glucose-1-P, glucose-6-P, fructose-6-P and fructose-1, 6-P were measured after experimental anaerobiosis.
• 2.2. The energy charge decreased from 0.84 to 0.07/0.69 within 6–9 hr of anaerobiosis.
• 3.3. During long term anaerobiosis there was no change from 0.70/0.69.
• 4.4. The concentrations of glucose, glucose-6-P and fructose-1,6-P increased somewhat during an initial phase of anaerobiosis.
• 5.5. The data are discussed with respect to the regulation of energy metabolism, especially during the transition of aerobic to anaerobic metabolism.
• 6.6. It is concluded that this transition is accomplished within 6–12 hours.

     

Temperature acclimatization in the filtering rates and oxygen consumption of Daphnia ambigua scourfield

• 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.

     

Specific dynamic action (SDA) in the supralittoral isopod,Ligia pallasii: Effect of ration and body size on SDA

• 1.1. Ration and body size effects on specific dynamic action (SDA) were investigated in the supralittoral isopod Ligia pallasii using seaweed and chemical diets.
• 2.2. SDA increased asymptotically with ingested meal size for all diets.
• 3.3. Body weight had a significant positive effect on SDA for only one of the six diets tested, but weak tendencies were present in the data for the other diets.
• 4.4. SDA appeared to increase geometrically with increasing concentration of amino acids at high ration levels.

     

Effects of temperature and acid stress on hatching,survival capacity,metabolism and postural reflexes in caenid mayflies (ephemeroptera)

• 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.

     

Carbohydrate metabolism during osmoregulation in Chasmagnathus granulata dana, 1851 (crustacea,decapoda)

• 1.1. Since glucose is one of the main energetic substrates for general metabolic processes in crustaceans, analysis of carbohydrate levels can furnish information on the energy metabolism of intact animals during osmoregulation.
• 2.2. Different groups of Chasmagnathus granulata were transferred to different salinities (0 and 40%), and the glucose and glycogen concentrations in blood, gills, muscle and hepatopancreas were determined at the beginning of the experiment and 24, 72, 168 and 360 hr after the salinity changes.
• 3.3. Differences in tissues carbohydrate levels were observed between summer and winter, that reflected differences in reserve mobilization.
• 4.4. In the summer, hypo- and hyperosmotic shocks induced an increase in carbohydrate levels in almost all tissues studied, indicating gluconeogenesis.
• 5.5. In the winter, a carbohydrate mobilization occurred only in the gills and hepatopancreas after both osmotic shocks.
• 6.6. Thus, the substrate reserve used for energy production required for osmoregulation seems to be dependent on the season and tissues.

     

Human-induced tachycardia in wild and tame mallard (Anas platyrhynchos)

• 1.1. The effect of regular handling on fear reactions was investigated in mallard (Anas platyrhynchos) by exposing six hand-reared and four wild ducks to an approaching human being and recording heart rates with an external ECG device.
• 2.2. All ducks reacted to the approach with tachycardia, but the response was significantly less in tame birds.
• 3.3. Hand-reared females showed less response than males. No sex-linked differences were apparent in the wild ducks.
• 4.4. Decreasing responses throughout the experiments were only found in tame birds.
• 5.5. Fear or stress reactions can apparently be diminished through habituation induced by regular handling.

     

Cold acclimation during the wintering of diapausing pupae of Pieris brassicae (lepidoptera)

• 1.l. A 2 month treatment at 5°C, beginning 14 days after larvonymphal ecdysis, leads to considerable physiological modifications of diapausing Pirn's brassicae pupae.
• 2.2. It leads to mechanisms of cold acclimation which are reflected by increased metabolic rates when measured at different temperatures.
• 3.3. This phenomenon affects energy metabolism as well as protein synthesis, but with different modalities.

     

The effect of myo-inositol on the ability of Ditylenchus dipsaci,D. myceliophagus and Anguina tritici to survive desiccation

• 1.1. The effect of myo-inositol on the ability of three species of nematodes to survive desiccation has been studied.
• 2.2. Survival rates obtained from worms treated with an inositol bathing medium were compared with survival rates of worms treated with distilled or tapwater media.
• 3.3. Highest survival rates were found in those nematodes that were placed in an inositol solution prior to desiccation.
• 4.4. Tapwater facilitated higher revival rates than did distilled water in both D. dipsaci and D. myceliophagous.
• 5.5. No such differences were found for A. tritici.
• 6.6. The results are discussed in relation to the possible mechanisms of protection afforded by the different bathing media.

     

Aerobic metabolism,octopine production and phosphoarginine as sources of energy in the phasic and catch adductor muscles of the giant scallop placopecten magellanicus during swimming and the subsequent recovery period

• 1.1. The energy contributions of aerobic metabolism, phosphoarginine, ATP and octopine in the adductor muscles of P. magellanicus were examined during swimming and recovery.
• 2.2. A linear relationship was observed between the size of the phosphoarginine pool and the number of valve snaps. A linear increase in arginine occurred during the same period.
• 3.3. Octopine was formed during the first few hours of recovery, particularly in the phasic muscle.
• 4.4. The restoration of the phosphoarginine pool appeared to be by aerobic metabolism.
• 5.5. It is concluded that the role of octopine formation is to supply energy when the tissues are anoxic and to operate at such a rate as to maintain the basal rate of energy production.

     

Effects of salinity and temperature on oxygen consumption in a freshwater population of Palaemonetes antennarius (Crustacea,decapoda)

• 1.1. After step-like increases in salinity the shrimps exhibit the smallest increase in oxygen consumption in the lower salinity range. At higher salinities the shrimps show longer recovery times and greater increases in the metabolic rate after salinity shock.
• 2.2. In steady-state experiments, the shrimps display the lowest oxygen consumption rates near the isosmotic point. The lowest metabolic rates occur at salinities of 3‰ and 10‰ At salinities of 20‰ and above the rate of metabolism increases by 20–30%.
• 3.3. The calculated osmoregulatory work for animals in fresh water amounts to only 2.7% of routine metabolism and drops to 1.1% for shrimps in 3‰ and 0.7% in 5‰ salinity.
• 4.4. Locomotory activity in the form of position change was not responsible for the increased oxygen consumption of the animals after salinity shocks. A “tentative swimming activity” by fast and frequent beating of the pleopods without position change may be an important factor in the increase of metabolic rates.
• 5.5. In its temperature response, the brackish water population has a higher metabolic rate than the freshwater one. Between 5 and 35°C Q ₁₀-values range from 4.01 to 1.37.

     

Seasonal variation in the metabolic rates and Q10-values of the fingernail clam,Sphaerium striatinum lamarck

• 1.1. Metabolic rates were highest during periods of maximum reproduction.
• 2.2. The exponent of the metabolic rate-weight equation varied seasonally, rates of metabolism of small animals exhibited greater annual fluctuations than those of large animals.
• 3.3. Absolute and weight-specific Q₁₀s (determined at 5–10°C above field temperatures) for smaller clams were greatest in the winter; absolute values of Q₁₀ were highest for larger individuals in the summer.
• 4.4. Small clams had Q₁₀ < 1.0 in the summer; Q₁₀-values for larger clams were near 1.0 at this time.
• 5.5. 38.9% of the total energy assimilated by the population annually was allocated to metabolism, which is near the low end of the range of values reported for freshwater molluscs, suggesting that this species can partition a large amount of energy to growth and reproduction.

     

The effects of artificial solar radiation on wind-stressed tufted titmice (Parus bicolor) and Carolina chickadees (Parus carolinensis) at low temperatures

• 1.1. Changes in metabolic rates and behavior were observed in tufted titmice (Parus bicolor) and Carolina chickadees (Parus carolinensis) exposed to varying conditions of artificial solar radiation, wind, and temperature in a wind tunnel experiment.
• 2.2. During the wind-on condition, both species showed a significant decrease in mean metabolic rates in the high radiation treatments when compared to the low radiation treatments (P < 0.05).
• 3.3. Titmouse orientation, posture and level of activity were significantly affected by radiation and wind conditions.
• 4.4. Metabolic rates observed in the wind tunnel treatments without wind and at low radiation did not significantly differ from similar standard metabolic (black box) treatments (P > 0.05).
• 5.5. Activity levels did not appear to directly affect metabolic rates observed in the wind tunnel treatments.