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.

     

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.

     

The influence of seasonal changes on energy metabolism in Mytilus edulise (L.).—III. Anaerobic energy metabolism

• 1.1. Seasonal changes in the accumulation of end products after 48 hr of exposure to air and in the composition of the free amino acid pool were studied in Mytilus edulis.
• 2.2. The accumulation levels of succinate and acetate showed only weak seasonal changes.
• 3.3. Conversion of succinate to propionate was high in summer and virtually zero in winter
• 4.4. Alanine and most other free amino acids were present in relatively high concentrations in summer and early autumn and reached minimal values in winter and early spring.
• 5.5. Exceptions were glutamate, aspartate and taurine, which showed hardly an season related changes and glycine, which changed inversely to the majority of the free amino acids.
• 6.6. The anaerobic formation of alanine was inversely proportional to the endogenous concentration.
• 7.7. The only other free amino acids affected by anaerobiosis were glutamate and aspartate, which respectively increased and decreased under these conditions.

     

Larval Musca domestica lipophorin biosynthesis

• 1.1. Larval Musca domestica lipophorin biosynthesis was studied in vitro.
• 2.2. The newly synthesized lipophorin has a density a little lower than the circulating lipophorin after 1 hr of incubation. After 3 hr of incubation the fat body cells transfer lipids to the lipophorin that attains the density of circulating lipophorin.
• 3.3. The lipophorin synthesized in vitro is identical to circulating lipophorin in density and in electrophoretical behavior.
• 4.4. However these two molecules must have differences since the circulating lipophorin transfers lipids to fat body cells while the synthesized in vitro does not.
• 5.5. The biosynthesis of Musca lipophorin shows differences with the Manduca sexta lipophorin biosynthesis.

     

Seasonal variation in plasma colloid osmotic pressure in the bat,Antrozous pallidus

• 1.1 The body weight (BW), hematocrit and plasma colloid osmotic pressure (COP) of adult and juvenile pallid bats maintained under constant laboratory conditions were measured periodically from August through April.
• 2.2. In the adult, BW and plasma COP showed seasonal cycles with peaks occurring in December and October through December respectively. A significant seasonal correlation between BW (fat) and plasma COP was found.
• 3.3. In the juvenile, a seasonal cycle was found for plasma COP, but the peak value was reached later in the year than in the adult. The need for a minimal fat content to support hibernation in the juvenile bat was suggested.
• 4.4. Seasonal changes in plasma volume appear to alter plasma COP: the quantity of circulating plasma protein appears to remain constant.

     

Seasonal changes in plasma prolactin concentration and carcass lipid levels in the lesser snow goose (Anser caerulescens caerulescens)

• 1.1. Plasma prolactin levels did not differ significantly between groups of birds collected at different times during the first year of life.
• 2.2. In adult males and females, highest plasma prolactin concentrations were evident in June (20.7 ± 7.8 and 20.4 ± 4.4 ng/ml respectively), probably associated with the incubation of eggs and rearing of young in the nest, whereas plasma prolactin levels in adult males and females collected at other times of the year were relatively stable and did not differ significantly between groups.
• 3.3. With the exception of the adults sampled in June, the prolactin levels in the adults were in the same range as those in the embryo gosling and yearling Snow Geese.
• 4.4. The concentrations of fat in both mature and immature birds was not related to the plasma prolactin concentration; maximal concentrations of carcass fat were observed during the northerly migration whereas maximum concentrations of prolactin were observed at the end of incubation when fat deposits were depleted.

     

Lipid components and utilization in consumers of a seagrass community: An indication of carbon source

• 1.1. The lipid components of three animals, the rock crab Nectocarcinus integrifons, the rock flathead Platycephalus laevigatus and the southern garfish Hyporhamphus melanochir, feeding in the seagrass beds at Corner Inlet, Victoria, Australia have been examined in detail in order to provide further information on seagrass community structure.
• 2.2. Biological marker compounds detected within animal gut content material were used to recognize dietary sources and then utilized by community members.
• 3.3. Both H. melanochir and N. integrifons have been shown to ingest and to varying degrees incorporate seagrass lipid material, thus further confirming the importance of seagrass carbon in the Corner Inlet environment.
• 4.4. The southern sea garfish H. melanochir is observed to remove C₁₈ PUFAs (polyunsaturated fatty acids) from ingested seagrass material.
• 5.5. Seagrass sterols are altered during incorporation into the lipids of this fish.
• 6.6. Lipid-rich digestive juices play a role in the digestive processes of all three animals.
• 7.7. Components tentatively identified as (NMI) (non-methylene interrupted) fatty acids have been detected in the lipids of the garfish H. melanochir and the crab N. integrifons.
• 8.8. The fecal material of all three animals represent possible sources of these lipids (NMI acids) in Corner Inlet sediments.
• 9.9. Based on lipid compositional data, N. integrifons feeds on Posidonia australis detritus and associated epiphyte material.
• 10.10. The removal of both plant and epibiota cellular lipids along the digestive tract of the crab was observed, although structural components such as long chain mono- and α,ω-dicarboxylic acids, which have been previously recognized as seagrass marker lipids are not directly absorbed.

     

Metabolic utilization of leucine in a fat and a lean line of chicken

• 1.1. In vivo incorporation into body lipids and breast muscle proteins from l-[U-¹⁴C]leucine was studied in genetically lean or fat male chickens, fed or starved, 1 or 24 hr after intraperitoneal injection.
• 2.2. Lipogensis and portein synthesis from labelled leucine were significantly higher in fat chickens than in lean birds, particularly in those in the fed state.
• 3.3. Radioactivity in the free amino acid pool was greater in fat birds irrespective of the nutritional state.
• 4.4. However, utilization of injected l-[U-¹⁴C]leucine for lipogenesis was no more than 2%.

     

Lipid changes in blood serum and tissues of the Egyptian Cobra “Naja haje haje” during the hibernation cycle

• 1.Total lipids, free fatty acids, triglycerides, phospholipids and total cholesterol in blood serum, liver, brain, cardiac and skeletal muscles of Naja haje haje were determined during the different phases of the hibernation cycle.
• 2.A sharp decrease in the level of total lipids of blood serum and all tissues occurred during hibernation. Upon arousal, lipogenesis is commonly restored.
• 3.Elevated concentrations of serum free fatty acids predominated in pre-hibernation and hibernation periods, while the tissues recorded highly significant declines during hibernation.
• 4.Occurrence of marked decreases in triglycerides contents of serum and tissues except the cardiac muscles in the hibernation and arousal phases.
• 5.Sharp increases in the phospholipid contents of blood and the selected tissues were recorded during hibernation. The level declined in both liver and cardiac muscles in arousing animals.
• 6.Total cholesterol level was lowered in blood during hibernation. The cardiac muscles showed a highly significant decrease while liver, brain and skeletal muscles showed elevations in the same phase.

     

Seasonal effects of prolactin on aspects of carbohydrate and lipid metabolism in the goldfish,Carassius auratus

• 1.1. Diurnal and seasonal variations of certain aspects of carbohydrate and lipid metabolism to ovine prolactin (PRL) treatment in the goldfish, Carassius auratus, were examined.
• 2.2. PRL treatment late in the light phase of a long photoperiod during spring depletes liver glycogen stores. During fall liver glycogen levels are not affected by PRL treatment in fishes acclimated to long or short photoperiods. PRL is hypoglycaemic in fall and spring.
• 3.3. PRL administered late in the light phase of a long photoperiod during spring increases plasma and liver total lipids and plasma cholesterol, while decreasing plasma triglycerides. In fall PRL may increase or decrease plasma organic-bound P levels dependent upon injection time.

     

Seasonal changes of circulating blood parameters in the grass snake Natrix natrix natrix L.

• 1.1. Seasonal changes of circulating blood parameters of Natrix n. natrix were evident and involved both sexes to the same extent.
• 2.2. A significant decrease in red cell count, haematocrit and haemaglobin concentration in the mating period, and an increase in those parameters and mean cell volume in autumn were observed, and haemodilution during winter torpor.
• 3.3. The changes during the breeding season had probably a hormonal background; in winter, they resulted first of all from a decreased erythropoietic activity and, to a lesser extent, from an increased red blood cell breakdown rate. However, the possibility that some erythrocytes were withdrawn from the circulation cannot be excluded.
• 4.4. Winter lymphocytopenia, eosinocytopenia and neutrophilic granulocytosis in females during egg laying were expressions of changes of leucocyte formula.
• 5.5. Seasonal cyclicity was found only with respect to the white cell count in males and the eosinophile fraction in males and females.
• 6.6. Probable reasons for, and mechanisms of the changes in blood composition are discussed.

     

Dehydration does not influence the summer versus winter thermal adaptation changes in rabbits (oryctolagus cuniculus), living in natural photoperiod

• 1.1.|Resting metabolic rate of laboratory rabbits kept indoors is susceptible to seasonal fluctuations and is higher in winter than in summer.
• 2.2.|Thermoneutral zone of rabbits under these conditions may shift downwards in winter and upwards in summer.
• 3.3.|Both of these adjustments in thermoregulation seem to be related to the seasonally changing photoperiod.
• 4.4.|Dehydration does not influence these thermoregulatory adaptive changes.

     

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.

     

Blood lipids of the small octopus,Octopus tehuelchus (mollusca,cephalopoda) at different stages of sexual maturation

• 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.

     

Accumulation,distribution and toxicity of selenium in the adult house fly,Musca domestica

• 1.1. Accumulation and distribution of dietary Se in relation to mortality was investigated in adult house flies.
• 2.2. The midgut preferentially accumulated Se and thereby limited toxicity.
• 3.3. Midgut Se concentrations were from 6- to 107-fold higher than in carcass, and from 15 to 71% of the total Se was associated with midgut.
• 4.4. When dietary levels of Se were raised the midgut saturated at 15 μg Se/g tissue, followed by a rise in carcass levels to greater than 0.5 μg Se/g tissue and increased mortality.
• 5.5. Se levels in lysosomal fractions were from 3- to 50-fold higher than in other subcellular fractions, suggesting that Se is sequestered in lysosomes.
• 6.6. Se added to drinking water was toxic at 4–8 ppm.

     

In vivo levels of aminoacyl-tRNA species during acclimatization of the carp Cyprinus carpio

• 1.1. The behaviour of the tRNA population during the acclimatization process was studied, examining the intracellular levels of aminoacylated-tRNAs in livers from summer and winter adapted carps (Cyprinus carpio).
• 2.2. The in vivo content of Val-tRNA, Ala-tRNA and Met-tRNA decreased significantly during the summer season, in which Val was 80%, Ala 47% and Met 54% with respect to the values attained in winter.
• 3.3. The half-life for the nonenzymic deacylation showed significant variations for the two populations of aminoacyl-tRNA obtained from summer and winter acclimatized fish.

     

Seasonal changes of lipids and fatty acids in oyster tissues (Crassostrea virginica) and estuarine particulate matter

• 1.1. Lipid concentration in adductor muscle ranged from 2–68, in visceral mass from 5–28, in mantle and gill from 5–20 and in heart from 27.8–79 mg/g wet tissue. Particulate matter lipids varied from 1.0–2.6 mg/1 of estuarine water.
• 2.2. Neutral and polar lipids ranged from 25–38% of the total lipids in the oyster tissue and from 62–75% of the estuarine particulate organic matter.
• 3.3. Seasonal maxima of lipid concentrations varied among oyster tissues. Peak particulate lipids occurred in November.
• 4.4. It is proposed that seasonal variation in oyster lipids was more related to reproductive cycles than to food lipid supply.

     

Comparative study on the fatty acid and lipid composition of four marine fish larvae

• 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.

     

Fatty acid profile of the digestive gland and mantle in the bivalve Macoma balthica

• 1.1. Digestive gland and mantle fatty acids were studied in spring and summer in the bivalve Macoma balthica off the southern coast of Finland. The presence of lipids was also examined histochemically in various clam tissues.
• 2.2. the neutral lipid content of the digestive gland increased ca 4.5-fold during the annual growth period.
• 3.3. Neutral lipid fatty acids of the digestive gland, of which palmitoleic, eicosapentaenoic and palmitic acids were predominant, were clearly distinguished from phospho- and glycolipid fatty acids.
• 4.4. The degree of unsaturation of phospholipid fatty acids was higher in the cold season both in the digestive gland and mantle, mainly due to the titer of eicosapentaenoic acid.