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1.
  • 1.1. The copepod Tisbe holothuriae was collected from the Saronicos gulf of Greece and cultured in the laboratory, under dif'erent combinations of temperature and salinity and as well as different types of food.
  • 2.2. The content of C, H and N in females was measured.
  • 3.3. As temperature increases and salinity declines from 38%, the content of C, H and N per individual decreases.
  • 4.4. The type of food influences the carbon and hydrogen content per individual, while the nitrogen content is relatively constant.
  • 5.5. The percentage content of C, H and N in females without egg sacs and females carrying their first newly formed egg sacs do not differ significantly
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2.
  • 1.1. The weight and energy content of sloughed skins of 92 individual snakes of 22 different species in three families were measured.
  • 2.2. Weight and total energy content of shed skins were highly correlated with body weight.
  • 3.3. The heat of combustion (kJ/g) of sloughed skins varied significantly among families and was higher in species having unkeeled scales than in those with keeled scales.
  • 4.4. The presence of keels significantly affected weight of skins, even when skin weight is adjusted for covariance with body weight.
  • 5.5. Neither body weight nor ambient temperature significantly affected the heat of combustion of sloughed skins.
  • 6.6. The energy content of shed skin, expressed as a proportion of daily metabolism, decreased with ambient temperature, but the effect is minimized in large snakes.
  • 7.7. Small snakes expended relatively less energy in sloughed skins than large snakes when the expenditure is expressed in terms of total daily metabolized energy.
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3.
  • 1.1. In teleost fish, sex pheromones are involved in advanced phases of reproduction, priming actions influencing oocyte maturation and ovulation in females, and spermiation in males; releasing actions involving attraction of prospective mates and triggering spawning behavior and release of gametes.
  • 2.2. In the African catfish Clarias gariepinus, sex pheromones were recently demonstrated to also influence earlier phases of the gonadal cycle, i.e. ovarian development in females.
  • 3.3. Aspects of interaction between sexes in emission of the pheromones, their source and identity are reviewed.
  • 4.4. The possible function of pheromonal stimulation in the natural environment and implications for fundamental and applied research methodologies are discussed.
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4.
  • 1.1. Over an 8-year period, 19 biochemical parameters have been determined at various ages in the blood serum of 92 clinically healthy Lechwe waterbucks (Kobus leche), 33 males and 59 females.
  • 2.2. Significant differences have been noted with age. In neonates, the lowest values of total proteins, glucose, creatinine, urea, AST, ALT and iron have been noted; the highest ones have been seen for cholesterol, alkaline phosphatase, calcium and phosphorus.
  • 3.3. With regard to sex, raised values of glucose, urea, alkaline phosphatase and ALT, and lowered values of cholesterol, have been noted in juvenile females compared with males of the same age.
  • 4.4. In adult females, higher levels of urea and cholesterol and lower levels of glucose, triglycerides and natrium have been recorded compared with males.
  • 5.5. With sex and age, no significant changes have been found in the levels of GGT, magnesium, chlorides and copper.
  • 6.6. Out findings are discussed with those abstracted from the literature for related species.
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5.
  • 1.1. A charcoal adsorption assay demonstrated a large variance in androgen binding ability in female spotted hyaenas.
  • 2.2. A positive correlation between plasma androgen binding ability and ovarian steroid concentrations was demonstrated in adult females.
  • 3.3. The strong plasma binding affinity for testosterone and dihydrotestosterone (DHT) (nM) together with the lack of cortisol and weaker oestradiol-17β binding suggests that a specific androgen binding substance, possibly a protein, is present in adult females of this species.
  • 4.4. The lack of high affinity binding in male spotted hyaenas is unusual and deserves further investigation.
  • 5.5. Some androgen binding in all, including males and immature animals suggests that albumin may bind some plasma androgens in this species.
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6.
  • 1.1. Larvae of the bromeliad crab, Metopaulias depressus Rathbun, were reared in the laboratory, and changes in dry weight (W), ash-free W (AFW), carbon, nitrogen, hydrogen, protein, lipid, carbohydrates and respiration rate were measured during development from hatching to metamorphosis.
  • 2.2. Development was successful in rain-water from bromeliads (pH < 5–6), but not in river water from the same region (pH 8). It is abbreviated, with two non-feeding zoeal stages (2.5–3.5 days each) and a feeding megalopa (8.5–10 days). Development to metamorphosis can also be completed in the absence of food (facultative lecithotrophy).
  • 3.3. Dry weight and other absolute biomass values per individual vary significantly between different hatches, whereas changes in the relative (% of W or AFW) composition follow quite invariable patterns: ash increases from hatching through the first part of megalopa development, organic biomass decreases concurrently.
  • 4.4. Elemental and biochemical data show that lecithotrophy of the zoeal stages as well as continued endotrophic development in the megalopa depend chiefly on degradation of lipid reserves and less on protein. No significant growth was observed in organic constituents when food was available, but without food the megalopa reached metamorphosis with only half the lipid and less than two thirds the protein of fed siblings.
  • 5.5. The relationship between C and lipid is similar in M. depressus larvae as in planktotrophic marine crab larvae, whereas that between N and protein differs; it indicates the presence of unusually large quantities of unidentified non-protein N.
  • 6.6. Exuvial losses of late premoult biomass or energy are very low in the zoeal stages (2 and 3%), but increase in the megalopa (16% in W, 10% in C, 7–8% in N, H and energy).
  • 7.7. Respiration rate per individual increases gradually during larval development (0.6–0.8 μg O2/hr). Starved megalopa larvae reveal lower individual but higher W-specific metabolism than fed larvae.
  • 8.8. Bioenergetic traits of abbreviated larval development are discussed in relation to those known from regular (planktotrophic marine) development of brachyuran crabs. M. depressus is highly adapted to life and development in a physically extreme terrestrial environment.
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7.
  • 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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8.
  • 1.1. Inductively coupled plasma atomic emission spectroscopy (ICP-AES) was used to measure iron concentration in several body tissues throughout the life cycle of the lamprey, Petromyzon marinus L.
  • 2.2. Iron concentration in the liver rises sharply during metamorphosis, decreases in parasitic adults, and falls to the lowest value in upstream migrants.
  • 3.3. In the intestine, the concentration of this metal is highest in the larval stage, but values decline steadily through transformation to their lowest levels in parasitic adults.
  • 4.4. Dorsal skin has, on average, three times the iron content of ventral skin and it is only in upstream migrants that the levels of both regions increase significantly over those of other stages.
  • 5.5. Differences in iron concentration in tissues of larval and adult lampreys reflect changes which take place at metamorphosis.
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9.
  • 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.
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10.
  • 1.1. Body temperatures of 69 adult lined snakes collected in the field were recorded along with associated air and substrate temperatures.
  • 2.2. There was no difference between the mean body temperature of males and females or between gravid and non-gravid individuals.
  • 3.3. Body temperatures differed significantly from either air or substrate temperatures.
  • 4.4. Lined snakes appear to maintain an activity temperature range by use of selected microhabitats.
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11.
  • 1.1. Metabolic rate (MR) and water budget (WB) components of cave and camel crickets are directly related to size and temperature.
  • 2.2. MR increases most rapidly with size for insects in general followed by cave crickets (females > males), and lastly, camel crickets (no sex differences).
  • 3.3. Metabolic thermal sensitivity of cave crickets (males > females) is much greater than camel crickets.
  • 4.4. WB components parallel MR relations.
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12.
  • 1.1. The lipid and fatty acid composition from the plasma and hemocytes in Octopus tehuelchus at different stages of sexual development, was determined.
  • 2.2. The highest content of lipids was found in females engaged in egg development, and the lowest in post-spawning and brooding females. Highest levels occurred during the autumn season in both sexes.
  • 3.3. Changes were mainly due to triacylglycerols and diacylglyceryl ethers.
  • 4.4. The plasma fatty acid composition did not demonstrate significant changes at different stages of maturation. The arachidonic acid (20:4 ω 6) was present at surprisingly high levels.
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13.
  • 1.1. Progesterone levels in Mytilus edulis males and females during the annual reproductive cycle were analysed in the whole animal and in the gonads using gas-liquid chromatography and radioimmunoassays.
  • 2.2. The high hormone levels in the whole animal were observed in July and October, coincident with the main spawning seasons.
  • 3.3. The levels of progesterone in gonad extracts also show a maximum in summer (July).
  • 4.4. The patterns of the progesterone levels in males and females throughout the annual reproductive cycle are similar.
  • 5.5. These data are discussed in relation to the role of progesterone in the regulation of sex-specific processes, particularly gametogenesis.
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14.
  • 1.1. Body temperature, oxygen consumption, CO2 production and muscle protein degradation rate were measured in the three quail lines selected for body size, a random bred line (RR) and two lines selected for large (LL) or small (SS) body size.
  • 2.2. The body temperature at 15 weeks of age was highest for small body size line and lowest for large body size line.
  • 3.3. The body temperature, oxygen consumption and CO2 production of females were significantly higher than that of males.
  • 4.4. The fractional degradation rate of muscle protein of SS, RR and LL lines were measured as 2.4, 1.6 and 1.2% per day in male, and 2.6, 1.7 and 1.4% per day in female.
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15.
  • 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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16.
  • 1.1. Particulate guanylate cyclase and receptors for E. coli heat-stable enterotoxin were solubilized from the rat intestinal cytoskeletal compartment using Lubrol-PX and KC1.
  • 2.2. Thirty to forty percent of the ST receptor and guanylate cyclase activities were extracted from the lipid layer with Lubrol-PX alone.
  • 3.2. Seventy percent of the remaining activities were solubilized from the cytoskeleton with Lubrol-PX and KCl.
  • 4.3. Guanylate cyclase solubilized from either compartment exhibited similar reaction kinetics.
  • 5.4. Both high- and low-affinity classes of ST receptors were solubilized from the lipid and cytoskeleton compartments.
  • 6.5. In the presence of ATPγS, ST selectively activated the guanylate cyclase solubilized from the cytoskeleton compared to that solubilized from the lipid bilayer.
  • 7.6. Crosslinking experiments demonstrated a preferential solubilization of the 130 kDa receptor subunit from the cytoskeleton and the 56 kDa subunit from the lipid bilayer.
  • 8.7. Development of a procedure to solubilize ST receptors and guanylate cyclase from the intestinal membrane cytoskeleton will permit purification and further detailed studies of the coupling of these activities.
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17.
  • 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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18.
  • 1.1. Monoamine neurotransmitters (epinephrine, norepinephrine, dopamine, serotonin and some of their metabolites (DOPEG, MHPG, DOPAC, 5-HIAA) were measured by HPLC in extracts from telencephalon (TEL) and diencephalon-midbrain (DM) before, during and at the end of metamorphosis.
  • 2.2. During metamorphosis MHPG increased and 5-HIAA decreased in TEL and DM while DOPEG decreased only in DM.
  • 3.3. Monoamine levels were greater in the TEL and a larger increase in MHPG occurred there.
  • 4.4. Captivity without metamorphosis also caused a significant depression of 5-HIAA in TEL and depression of DOPEG, MHPG and DOPAC in DM.
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19.
  • 1.1. All age groups gained mass during the active season, but mass-gain of adult females was delayed during lactation.
  • 2.2. The relationship of body mass to metabolic rate varied widely; when the relationship was significant, R2 varied from 10.3 to 72.6%. Body mass affects VO2 more during lactation than at any other period.
  • 3.3. Mean VinO2 of adult males was higher in June than that of adult, non-lactating females.
  • 4.4. VO2 of reproductive females was significantly higher during lactation than during gestation or postlactation because specific VO2 varied. Specific VO2 of non-reproductive females declined over the active season.
  • 5.5. Specific VO2 of all age groups declined between the premolt and postmolt periods. The reduced maintenance costs can contribute 20–46% to daily growth.
  • 6.6. Observed VO2 was lower than the value predicted from intraspecific or interspecific Bm:M regressions.
  • 7.7. VO2 of wild-caught marmots was lower than that of marmots maintained in the laboratory, probably because of dietary differences.
  • 8.8. Because basal metabolism is a stage on a food-deprivation curve, we suggest that basal metabolic rate is not an appropriate measure of the metabolic activity of free-ranging animals.
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20.
  • 1.1. Hematocrit, total protein and glucose values were determined in blood samples from 19 marsh harriers (Circus aeruginosus), 10 males and nine females.
  • 2.2. The different parameters were studied on the basis of the ranges described in other birds.
  • 3.3. There was a significant correlation between weight and blood glucose level.
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