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1.
  • 1.1. Both the post-moult, rockhopper (Eudyptes crestatus) and magellanic penguins (Spheniscus magellanicus) had significantly lower plasma total protein, albumin, urate, iron and potassium and higher alkaline phosphatase activity than pre-moult birds. In addition creatinine, conjugated bilirubin and inorganic phosphate in the magellanics; globulin, urate, calcium, alanine and aspartate transaminases in the rockhoppers were significantly decreased.
  • 2.2. There were significant differences in plasma bicarbonate, inorganic phosphate, alkaline phosphatase and iron concentrations between non-moulting adult and post-moult gentoo penguin (Pygoscelis papua) chicks.
  • 3.3. Absence or scarcity of the preferred nutrient requirement during the period preceding moulting could threaten the survival of any of the species, particularly of those of narrow dietary speciality.
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2.
  • 1.1. Oxygen consumption in six crustacean species from the continental shelf of the NW Gulf of Mexico was related to the ash free weight per dry weight (afdw) gram of the tissue excluding the exoskeleton, suggesting a close relationship to their life strategies.
  • 2.2. Dry weight exoskeleton proportion varied among species, with highest values recorded in callapid brachyuran crab species (46.8–52.5%) against the values recorded in portunid crab (45.8–48%) and the shrimp species (26.7–35.7%).
  • 3.3. Oxygen consumption was related to afdw in each species according to the expression y = axb, with b values ranging from 0.68 to 2.92.
  • 4.4. Rates of oxygen consumption per afdw/dw were larger in shrimps than in portunids and callapids, and was related to the morphophysiology and lifestyle of six species described; the former as the morphological design of the exoskeleton versus the muscle content in the species and the latter as the activity rate in the environment.
  • 5.5. The oxygen extraction efficiency, calculated from oxygen consumption, was higher in the eurytopic species Penaeus aztecus and Callinecies similis than in species restricted to the marine environment, hence considered as a response to environmental fluctuations.
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3.
  • 1.1. The digestion proteases in five marine species (Atlantic halibut, Hippoglossus hippoglossus (L); Dover sole, Solea solea (L); turbot, Scophthalmus maximus, (L); European lobster, Hommarus gammaarus (L); and the giant prawn, Penaeus monodon) have been compared by biochemical methods.
  • 2.2. The pH profiles for the hydrolysis of casein by extracts from the digestive systems of each species showed different characteristics; extracts from adult halibut, turbot and sole exhibited strong pepsin-like activity; whereas this enzyme was absent in P. monodon and in sole larvae.
  • 3.3. Although lobster extracts, from either the hepatopancreas or the stomach, showed peaks at pH values of 5.8 and 2.5, this latter activity did not hydrolyse a specific substrate for pepsin.
  • 4.4. Halibut and turbot digestive extracts contained an activity optimal at pH values in the region of 5.0 resembling a cathepsin-like enzyme; an activity which was not evident in the other species under similar experimental conditions.
  • 5.5. Although all species possessed trypsin-like activity, the pH profiles of activity in the neutral to alkaline region were unique to each species.
  • 6.6. The significance of these results is considered with respect to the anatomical differences in the alimentary systems of these species.
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4.
  • 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.
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5.
  • 1.1. Physiological responses of 13 adult female collared peccaries (Tayassu tajacu) to high quality and low quality diets, fed for 15 weeks, were examined. The low quality diet simulated energy and protein intake of peccaries during poor range conditions resulting from drought. Blood samples were collected after 10 and 15 weeks of dietary treatment; urine samples were collected after 15 weeks of treatment.
  • 2.2. Females receiving the low quality diet for 15 weeks lost 27.4% of their original body weight, compared to no weight change among high quality-fed females.
  • 3.3. Red blood cell counts, hematocrits, and hemoglobin concentrations were significantly greater among females fed a high quality diet compared to those receiving a low quality diet. High quality-fed females also had a higher mean corpuscular hemoglobin concentration. Plasma fibrinogen concentration was nearly twice as great among females receiving the low quality diet compared to the high quality group.
  • 4.4. Consumption of the low quality diet resulted in significantly elevated serum levels of nonesterified fatty acids, alkaline phosphatase, phosphorus, alpha-2 globulin and alpha globulin: beta globulin ratio.
  • 5.5. Consumption of the low quality diet resulted in significantly lowered serum levels of urea nitrogen, calcium, zinc, calcium: phosphorus, urea index, beta-1 flobulin, beta globulin: albumin ratio, thyroxine and triiodothyronine.
  • 6.6. Serum levels ofcreatinine, total bilirubin, glucose, cholesterol, gamma glutamyltransferase, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, potassium, copper, magnesium, sodium chloride, total protein and gamma globulin were unaffected by diet quality.
  • 7.7. Urine chemistry results suggested pH, osmolarity, albumin, creatinine phosphokinase, calcium and phosphorus concentrations might be useful indices for assessing nutritional status in female peccaries.
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6.
  • 1.1. Blood, liver, heart, testis, skin, eye, muscle and kidney samples were obtained from elephants (Loxodonta africana) in the Kruger National Park during a culling programme in April 1992.
  • 2.2. Gene products of 25 protein coding loci in L. africana were examined by horizontal starch-gel electrophoresis.
  • 3.3. Eighteen protein coding loci (72%) displayed monomorphic gel banding patterns whereas only seven (28%) displayed polymorphic gel banding patterns.
  • 4.4. Average heterozygosity values for adults, youngsters and the total population are respectively 0.058, 0.024 and 0.047.
  • 5.5. Relative gene diversities within and between populations are 84% and 16% respectively.
  • 6.6. Two population simulation programmes were utilized to predict the duration of the current variability present in this species, based on current genetic variation and gene transfer from one generation to the next.
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7.
  • 1.1. Osmotic measurements were made on the perivisceral coelomic and water vascular fluids of 4 species of northwest Pacific starfish and their stable sea-water media.
  • 2.2. Mean levels of both fluids were hyperosmotic in every species, often at statistically significant levels.
  • 3.3. For all species combined, mean hyperosmolality (mosmol/kg ± SE) of perivisceral coelomic fluid was 1.49 ± 0.17, and water vascular fluid 6.07 ± 0.74.
  • 4.4. The hyperosmotic nature of these fluids contributes to water balance, working in conjunction with madreporitic inflow and other factors.
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8.
  • 1.1. The presence of a renin-angiotensin-like system has been investigated in the Antarctic fishes Chionodraco hamatus (Fam. Channichthydae) and Pagothenia (Trematomus) bernacchii (Fam. Notothenidae).
  • 2.2. A renin-like activity is present in plasma and kidney of both the white blooded (Chionodraco) and the red blooded (Pagothenia) species.
  • 3.3. An angiotensin converting enzyme-like activity has been demonstrated in plasma, gills and kidneys of both species. The activity is inhibited by high temperature.
  • 4.4. From our data a renin-angiotensin-like system is present in the Antarctic fishes studied but the cascade of enzymes is active only at low temperatures.
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9.
  • 1.1. A model for target localization, developed for Squilla mantis, was modified for two other stomatopod species.
  • 2.2. While Squilla live in dim light, Odontodactylus scyllarus live in medium bright and Gonodactylus in extremely bright habitats.
  • 3.3. The critical zones for prey capture, selected by a decision neuron, were identified. These are bifurcated, stretching out for long distances.
  • 4.4. A much more limited critical zone is obtained by introducing a strike command neuron, which receives inputs only from the two central ommatidia in the middle band instead of from all six as does the decision neuron.
  • 5.5. The results correspond to the different behavior patterns in prey capture for the different species.
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10.
  • 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.
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11.
  • 1.1. Molecular polymorphism of tropomyosin from various muscle sources of the scallop, Patinopecten yessoensis, was investigated by electrophoretic and immunochemical methods.
  • 2.2. Treatment of the muscle sources with trichloroacetic acid (TCA) prior to tropomyosin preparation was found useful to prevent proteolytic degradation of this protein.
  • 3.3. Electrophoretic and immunochemical analysis revealed that at least six kinds of tropomyosin isoforms may exist in scallop muscle tissues.
  • 4.4. The tropomyosin isoforms showed tissue-specific distribution in amounts and molecular species among the various muscle sources.
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12.
  • 1.1. Fatty acid and lipid class composition were determined in larvae of four marine species: Atlantic halibut (Hippoglossus hippoglossus L.), plaice (Pleuronectes platessa), cod (Gadus morhua) and turbot (Scophthalmus maximus) at hatching and prior to first feeding.
  • 2.2. Total fatty acid content decreased in the four species with up to 50% reduction in one of the halibut groups. Docosahexanaoic acid (22:6 n-3) was especially utilized.
  • 3.3. Low lipid utilization was found in turbot in relation to the other three species.
  • 4.4. Water environmental temperature may explain some of the differences in the fatty acid utilization and the source of metabolic energy between cold water species (halibut, cod, and plaice) and temperate species (turbot), in the period from hatching to prior to first feeding.
  • 5.5. Relative amounts of neutral lipids and phospholipids were similar in plaice, cod and halibut, approximately 25% and 75% of total lipids, respectively, and were approximately constant during the yolk-sac stage. Neutral lipids were dominant for turbot at hatching, accounting for 53–55% of the total lipids, while phospholipids predominated prior to first feeding, being 56–59%.
  • 6.6. Phosphatidylcholine was catabolized in halibut, plaice and cod but not in turbot, while phosphatidylethanolamine tended to be synthesized in all four species.
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13.
  • 1.1. Fingerlings of intergenious hybrid Russian sturgeon (Acipenser guldenstadti) × beluga (Huso huso) weighing 22 g reared in water with salinity 18 ppt were fed nine diets differing in protein and fat content.
  • 2.2. The increase of dietary protein content (from 45 to 52%) improved the fingerlings growth rate, food and protein conversion efficiencies. No effect of further protein content increase to 60% was observed.
  • 3.3. The increase of dietary fat content from 10 to 20% positively influenced all growth results.
  • 4.4. The muscular lipid content increased following the increase in dietary fat due to accumulation of triacylglycerols.
  • 5.5. Distinctive leucopenia in neutrophils and leucophilia in lymphocytes following dietary protein and fat content increase were observed.
  • 6.6. It was concluded that within the analysed range of values the increase of dietary protein and lipid content improved the physiological status of sturgeon hybrid fingerlings.
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14.
  • 1.1. The organic composition of the body tissues of eight species of deep-sea aspidochirotid holothurian, collected between 500 and 4100m depth in the NE Atlantic Ocean, was obtained by the biochemical analysis of protein, lipid, carbohydrate and % ash.
  • 2.2. The major organic class was protein with soluble lipid the major soluble fraction in the ovary. Carbohydrate values were consistently low.
  • 3.3. The calorific value was significantly higher in the ovary than in the other tissues.
  • 4.4. The total body calorific content for two selected species, Benthothuria funebris and Mesothuria lactea, was 25.62 and 26.24J/mg ash-free dry weight (AFDW).
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15.
  • 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.
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16.
  • 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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17.
  • 1.1. A procedure is described for the analysis of sugars in insect hemolymph by high performance thin-layer chromatography.
  • 2.2. Densitometric scanning of spots after plate developments shows linear responses with most sugars in an analytical range of 125ng-2.0 /gmg; detection limits range from 30/2–60 ng.
  • 3.3. Quantitative measurements of trehalose, glucose and fructose can be made on hemolymph sample volumes of less than one microliter, allowing blood sugar analysis of individual insects.
  • 4.4. Hemolymph sugar determinations on six species of insects agree well with values reported in the literature, but mean values for a species often showed higher variability because samples were taken from individuals.
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18.
  • 1.The thermal coadaptation hypothesis predicts that (1) ectotherms experiencing a narrow range of body temperatures in the wild will evolve to perform well over a narrow range of body temperatures and that (2) the optimal temperature for performance will be equal to the preferred body temperature of the species.
  • 2.We tested the predictions of the thermal coadaptation hypothesis with black rat snakes (Elaphe obsoleta) and northern water snakes (Nerodia sipedon) because black rat snakes experience lower and more variable body temperatures than northern water snakes at our study site.
  • 3.We measured swimming speed, tongue-flicking speed, and striking speed in black rat snakes, and swimming speed and tongue-flicking speed in northern water snakes.
  • 4.Adult water snakes generally had narrower performance breadths and higher optimum performance temperatures than adult black rat snakes.
  • 5.Performance breadths were the same for swimming, tongue flicking, and striking within adult black rat snakes, but performance optima for these behaviours differed significantly. Performance breadths differed and performance optima were the same for swimming and tongue flicking within adult northern water snakes.
  • 6.The relative swimming performance of neonates of the two species was similar in breadth to that of adults, but the thermal optimum for neonate black rat snakes was higher than that of adults.
  • 7.Overall, our results provided support for the thermal coadaptation hypothesis.
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19.
20.
  • 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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