Cold tolerance of steinernematid and heterorhabditid nematodes

• 1.1. Nematodes survive subzero temperatures using either a freeze-avoiding or freezing-tolerant strategy. Steinernema anomali, S. feltiae, and Heterorhabditis bacteriophora were all found to be freezing tolerant.
• 2.2. The lower lethal temperatures were −22, −19 and −14°C for S. feltiae, H. bacteriophora and S. anomali, respectively.
• 3.3. Survival after prolonged freezing at −4°C was 6, 5 and 3 days for S. feltiae, H. bacteriophora and S. anomali, respectively.
• 4.4. Acclimation to lower temperatures increased freezing tolerance. The freezing tolerance of Heterorhabditis bacteriophora increased under a stepwise acclimation regime; S. feltiae acclimated better under a direct acclimation regime.

     

Anuran amphibia which are not acclimable to high salt,tolerate high plasma urea

• 1.1. The capacity of five anuran Amphibians (Bufo viridis B. regularis, Rana ridibunda, Hyla arborea and Pelobates syriacus) to acclimate to NaCl and urea solutions was investigated.
• 2.2. All species could be acclimated to relatively high concentrations of urea solutions, while only Bufo viridis and Hyla arborea could be acclimated to 500 mOsm/kg or higher NaCl solutions.
• 3.3. The plasma urea concentration in B. viridis and H. arborea was elevated to levels over 140 mmol/1.
• 4.4. The sum of plasma sodium and chloride concentrations did not increase over 400 mmol/l in any species.
• 5.5. Urine osmolality, which was normally low, increased, but never exceeded the plasma osmolality.
• 6.6. In the urea acclimation conditions, urine electrolytes diminished, similarly in all species in this study.
• 7.7. It is concluded that anuran Amphibians can tolerate high plasma urea concentrations, but only those species which can elevate it, either through retention or net synthesis, can be acclimated to high salt solutions.

     

The effects of acclimatization on body weight and oxygen consumption in Dipodomys panamintinus

• 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.

     

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.

     

Adaptation of fatty acid compositions to temperature—a study on planktonic crustaceans

• 1.1. Fats of freshwater crustaceans overwintering in an active form are richer in long chain polyunsaturated fatty acids (50%) than of those spending the winter in form of resting eggs (10%).
• 2.2. The former species (Cyclops vicinus, Eudiaptomus gracilis) increase the level of docosahexaenoic acid from about 10 to 25% in their phospholipids with decreasing environmental temperature.
• 3.3. Exposing warm-adapted Cyclops vicinus and Eudiaptomus gracilis to 5°C in laboratory brought about an increase in the phospholipid docosahexaenoic acid level from 10 to 24%.
• 4.4. Ability to adapt membrane fluidity to the temperature might be important for survival at low temperatures.

     

Evidence for hyporegulation in the calanoid copepod,Acartia tonsa

• 1.1. The euryaline calanoid copepod, Acartia tonsa, maintains haemolymph Na below that of the external medium in salinities above 34^o_oo (475 mM Na).
• 2.2. The measured transepithelial electrical potential. −9.97 ± 1.0 mV, indicates that Na is regulated out of electrochemical equilibrium.
• 3.3. Water osmotically lost in hyporegulation is replaced by Na-dependent absorption by the gut.
• 4.4. High osmotic water permeability is evidenced by the fact that with an increase in external salinity from 475 mM Na to 580 mM Na the copepod's drinking rate nearly doubles.
• 5.5. Sodium efflux measurements indicate that ionic permeability is much lower than other hyporegulating crustaceans.
• 6.6. The energetic advantage of hyporegulation in this species is considered.

     

The oxygen consumption rates of three gastrotrichs

• 1.1. The oxygen consumption rates for three sympatric species of marine gastrotrichs (anatomically similar, except that one contains hemoglobin) were measured with a Cartesian diver microrespirometer.
• 2.2. The rates for the two species without hemoglobin, Turbanella ocellata and Dolichodasys carolinensis, were 307.2 μl O₂ g⁻¹ hr⁻¹ and 108.0 μl O₂ g⁻¹ hr⁻¹, respectively, while the rate for the hemoglobin-containing species, Neodasys, was 208.9 μl O₂ g⁻¹ hr⁻¹.
• 3.3. The possession of hemoglobin by Neodasys (14% by volume) cannot be explained by an unusually high demand for oxygen.
• 4.4. Instead, the hemoglobin may be useful as an oxygen store providing continued aerobic metabolism in anoxic conditions, thus allowing Neodasys to exploit a different niche.

     

Seasonal changes of total lipids in the turtle Sternotherus odoratus

• 1.1. Seasonal variation in total lipids was examined in several body components of the turtle Sternotherus odoratus.
• 2.2. Carcass fat stores in both sexes were depleted during winter. Additionally, a decline in carcass lipids was associated with increases in gonadal mass.
• 3.3. Concentrations of liver lipids were maximal during August and minimal during winter.
• 4.4. Males showed little seasonal change in plasma lipid levels, whereas females had seasonal peaks temporally associated with ovarian development and carcass fat storage.
• 5.5. Ovarian concentrations of lipids were minimal after nesting and increased during fall.
• 6.6. Results suggest that S. odoratus uses stored fats both for reproduction and maintenance during winter.

     

The thyroid gland and temperature regulation in the prairie vole,Microtus ochrogaster and the chipmunk Tamias striatus

Absract

• 1.1. The basal metabolism of the vole, Microtus ochrogaster, a non-hibernator is about 80% below that expected for microtine rodents, while the basal metabolism of the chipmunk, Tamias striatus, is about 20% below that expected for small mammals.
• 2.2. Blocking thyroid secretion results in a 3°C improvement in the vole. and a 2°C improvement in the chipmunk, to the highest air temperature tolerated.
• 3.3. Blood levels of thyroxine in both species did not change as a function of ambient temperatures, whereas rates of radioiodine release were reciprocally related to ambient temperature.
• 4.4. There was no indication that the thyroid gland of the chipmunk was ever inactive either preceding, or during, hibernation.

     

Osmoregulatory adjustments by three atherinids (Leptatherina presbyteroides; Craterocephalus mugiloides; Leptatherina wallacei) to a range of salinities

• 1.1. Patterns of osmoregulation were studied in three species of Swan river atherinids (Leptatherina presbyteroides, lower estuarine and marine; Craterocephalus mugiloides, mid estuarine; Leptatherina wallacei, upper estuarine) over a wide range of salinities.
• 2.2. The plasma Na⁺ concentration was elevated with an increase in salinity.
• 3.3. Haematocrit and body water content decreased with acclimation to higher salinity.
• 4.4. All three species of atherinids osmotically regulated over a salinity range greater than that which these fish are reported to occur in.

     

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.

     

Comparative analysis of cuticular hydrocarbons in the Drosophila virilis species group

• 1.1. Chemical structures were determined for the cuticular alkanes, alkenes, and certain of the alkadienes for 11 D. virilis group species.
• 2.2. Male-specific hydrocarbons occurred in five species: these were 9-heneicosene in D. americana and D. novamexicana, 10-heneicosene in D. virilis, 5,13- and 5,15-pentacosadienes in D. kanekoi, and 9-pentacosene in one strain of D. lummei.
• 3.3. Hydrocarbon profiles of newly emerged flies always differed from mature files.
• 4.4. Relationships among the species, with respect to hydrocarbon profiles, were investigated by cluster analysis.

     

Patterns of fuel utilization by the thoracic muscles of adult worker ants. The use of lipid by a hymenopteran

• 1.1. Patterns of fuel utilization in the thoracic muscles of three species of ants have been established.
• 2.2. The thoracic muscles of Formica ulkei exhibit a typical Hymenopteran metabolic organization, relying exclusively upon carbohydrate oxidation for the provision of metabolic energy. This species feeds upon honeydew.
• 3.3. Pogonomyrmex californicus, a granivorous ant, exhibits a metabolic organization unprecedented for a Hymenopteran species. Its thoracic energy metabolism is based upon lipid oxidation.
• 4.4. Atta colombica, a fungus feeder, can metabolize both carbohydrate and fat, a versatility which is not typical of Hymenoptera.
• 5.5. It is concluded that patterns of fuel utilization in insects are not determined by phylogenetic inertia, but are selected to accommodate the activity patterns, feeding ecology and dietary regime of the species.

     

Biochemical variations in three species of prairie dogs (Cynomys)

• 1.1. Blood proteins were studied by polyacrylamide disc gel electrophoresis in three species of prairie dogs, Cynomys gunnisoni, C. leucurus, and C. ludovicianus.
• 2.2. The sera were separated into 13–15 fractions and the three species could be distinguished by both qualitative and quantitative differences in their serum patterns.
• 3.3. Qualitatively, variations in the occurrence and number of slow albumin fractions are diagnostic at the species leel.
• 4.4. Quantitative differences were most apparent in variation in the mobility of the major albumin fraction and the transferrin fraction.

     

Metabolic rate and body temperature of adult and juvenile hyrax (Procavia capensis)

• 1.1. Resting metabolic rates (RMR) below thermoneutrality in adult hyrax acclimated to 26, 15 and 10°C remained unchanged, i.e. thermal conductance (K) remained constant.
• 2.2. Conductance in juveniles decreased with acclimation to lower ambient temperatures (T_a).
• 3.3. Body temperature (T_b) dropped by 3.8°C in adults exposed to T_a of 30 – 5°C. The decrease was constant.
• 4.4. Body temperature fell by 1.5°C in juveniles exposed to T_a of 30 – 20°C but stabilized between 20 and 5°C.
• 5.5. The labile T_b, associated with behavioural strategies and lower than predicted RMR, can be seen as an energy-conserving mechanism of particular importance during winter conditions.

     

Lysosomal acid deoxyribonuclease from vervet monkey livers—II: Enzymic properties

• 1.1. Primate liver lysosomal acid DNase is an endonucleolytic enzyme.
• 2.2. The enzyme has both 3'- and 5'-nucleotidohydrolase activities.
• 3.3. The oligonucleotides produced by DNase are polymers mainly about 30 mononucleotides long.
• 4.4. The Arrhenius plot shows a discontinuity with a transition temperature at 47°C, with an activation energy of 107 kJ/mol below and 67 kJ/mol above this temperature.
• 5.5. The activation enthalpy is 104kJ/mol and the entropy −0.498 kJ/mol/K.
• 6.6. The enzyme is subject to substrate inhibition and the K_m value is 159 × 10⁻³mM DNA-P.

     

Seasonal variation in the energy metabolism in an estuarine crab,Chasmagnathus granulata (Dana, 1851)

• 1.1. The effects of seasonal variation on the carbohydrate and lipid metabolism of the Chasmagnathus granulata were investigated.
• 2.2. Glycemia is high in winter and summer and low in spring and fall.
• 3.3. The glycogen content in the hepatopancreas and muscle is higher in fall and winter, and decreases during spring and summer.
• 4.4. The muscle lipids are higher in summer, and decrease during fall and winter whereas hepatopancreas lipids are higher except in the fall.
• 5.5. The crabs show change in the metabolic pattern of lipids and carbohydrates during the seasons of the year.

     

Electrophoretic identification of bird species involved in collisions with aircraft

• 1.1. The utility of biochemical genetic methods of bird identification was investigated for some common species which create a hazard for commercial aviation in Ireland.
• 2.2. Sixteen enzyme loci were assayed in eight species, using starch gel electrophoresis; three larids, three corvids and two columbids.
• 3.3. Genera were distinguishable using all but two loci.
• 4.4. Differences within genera were small, but all species except for the gulls Larus argentatus and L. marinus, could be identified using one or more loci.
• 5.5. Arising from the success of the method using fresh specimens, a protocol for the electrophoretic identification of traumatized remains of strikes is suggested.

     

A comparative study of the respiratory properties and physiological function of haemocyanin in two burrowing and two non-burrowing crustaceans

• 1.1. Oxygen dissociation curves were constructed for the haemolymph of two non-burrowing, Galathea strigosa and Eupagurus bernhardus, and two burrowing crustaceans, C. cassivelaunus and Nephrops norvegicus. The p₅₀ at in vivo pH values and 10°C was 12.6 Torr in G. strigosa, 23 Torr in E. bernhardus, 3.1 Torr in C. cassivelaunus and 11.5 Torr in N. norvegicus.
• 2.2. The Bohr values (Δlogp₅₀/ΔpH) were high in all species ranging between −0.96 and −1.48. Cooperativity expressed as P₅₀ averaged 3.3, 3.8 and 3.8 in G. strigosa, E. bernhardus and N. norvegicus. respectively. A lower value of 2.2 was observed in C. cassivelaunus.
• 3.3. The oxygen affinity of the haemocyanin was relatively temperature independent, the values for ΔH at pH7.9 ranging between −5.1 and −18.1 kJmol⁻¹.
• 4.4. Haemolymph respiratory gas analysis showed values similar to those previously reported in crustaceans: p_aO₂ ranging between 44 and 107 Torr and p_vO₂ values between 18 and 24 Torr.
• 5.5. Pre-/post-branchial pH differences were small in G. strigosa, E. bernhardus and N. Norvegicus, but averaged 0.09 of a pH unit in C. cassivelaunus. p_aCO₂ and P_vCO₂ values ranged between 1.4 and 2.3 Torr.
• 6.6. In buried C. cassivelaunus both pre- and post-branchial oxygen tensions decreased, as did oxygen tension overall during respiratory pauses.
• 7.7. Cardiac output values were low, ranging between 59 and 71 ml kg⁻¹ min⁻¹ for all four species and calculated stroke volumes were realistic in terms of animal size.
• 8.8. In the non-burrowing species physically dissolved oxygen accounted for 5–21% of the oxygen transported to the tissues. In the burrowing species values of 40–77% were found.

     

Osmoregulation and temperature effects on water loss and oxygen consumption in two species of african scorpion

• 1.1. Aspects of the physiology of two southern African scorpions have been examined. The scorpions are the large desert species Parabuthus villosus (Peters) (Buthidae) and the more mesic, burrowing species Opisthophthalmus capensis (Herbst) (Scorpionidae).
• 2.2. Evaporative water losses were higher in Opisthophthalmus at all temperatures.
• 3.3. Analysis of haemolymph during prolonged desiccation showed good osmotic and ionic regulation in Parabuthus but no regulation in Opisthophthalmus.
• 4.4. Oxygen consumption of Parabuthus was measured after acclimation to 10 and 30°C. Metabolic rates were extremely low but there was no metabolic compensation to increased temperatures.