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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. The characteristics of both, motor and electroretinographic circadian rhythms in the crayfish Procambarus bouvieri, were examined.
  • 2.2. The correlation between both rhythms in intact and brainless crayfish, was obtained.
  • 3.3. The presence of at least two different but coupled oscillators responsible for the circadian variations in crayfish, is proposed.
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3.
  • 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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4.
  • 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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5.
  • 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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6.
  • 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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7.
  • 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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8.
  • 1.1. Muscle proteins from the chelae of six crayfish species and ten species of Uca were compared through disc electrophoresis (split gel technique).
  • 2.2. No intraspecies variation of the electrophoretic pattern was found.
  • 3.3. In interspecies comparisons all components (bands) were weighted individually and specified as ancestral or derived characters.
  • 4.4. In the crayfishes the phylogenetic trees constructed from electrophoretic and classical data were found to be congruent. In Uca some branches of either tree remained undefined. Each tree, however, helped complete the other one.
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9.
  • 1.1. A significant diurnal rhythm of net sodium flux was demonstrated in the freshwater clam Corbicula fluminea entrained to either a 12L:12D or 24L photoperiod.
  • 2.2. Highest net flux occurred during the dark hours on 12L: 12D. The overall mean net flux over 24 hr was not significantly different from a steady state condition.
  • 3.3. Net flux values of clams on a 24L photoperiod were negative and significantly lower than the net flux on a 12L:12D photoperiod.
  • 4.4. The 12L: 12D net sodium flux rhythm pattern is similar to rhythmic patterns of other physiological processes in another freshwater clam.
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10.
  • 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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11.
  • 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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12.
  • 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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13.
  • 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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14.
  • 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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15.
  • 1.1. This study compared the composition of the skin surface lipids (SSL) of cattle (Bos taurus) and of buffalo (Bubalis bubalis) steers at the same level of feed intake in a thermoneutral environment.
  • 2.2. There was about eight times less lipid per unit area of skin surface on the buffalo than on cattle.
  • 3.3. The distribution of the different lipid classes in the SSL of the two breeds was different. Compared to cattle, the buffalo SSL was characterized by smaller proportions of wax ester bands 2 and 3 and triglycerides.
  • 4.4. There were significant species differences in the fatty acid patterns of the individual lipid classes.
  • 5.5. The results are discussed in relation to the functional attributes of sebum.
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16.
  • 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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17.
  • 1.1. Rate of fluid absorption by eel (Anguilla rostrata) intestinal sacs in vitro reached seawater adapted values 3 days after transfer from freshwater to seawater.
  • 2.2. After 3 days in seawater oxygen consumption and Na-K-ATPase activity of intestinal mucosa had not increased over freshwater values.
  • 3.3. The weight of intestinal mucosa increased 32% during seawater adaptation as a result of an increase in the number of mucosal cells (hyperplasia).
  • 4.4. The rate of intestinal fluid absorption was reduced by 10−4 M ouabain and was not affected by 10−4 M acetazolamide.
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18.
  • 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.
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19.
  • 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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20.
  • 1.1. In great-horned owls food metabolizability, food intake and body weight were not significantly affected by cecectomy.
  • 2.2. Following cecectomy, water ingestion increased.
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