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1.
  • 1.1. The amount of sugar required for growth of Heliothis zea larvae on a chemically defined diet was determined.
  • 2.2. Larvae grew well on fructose, galactose, sucrose, trehalose and raffinose diets but not on diets containing more than 0.5% glucose.
  • 3.3. A starch diet did not promote rapid larval growth.
  • 4.4. Hemolymph trehalose levels in 12-day-old larvae ranged from none to 45μmoles/ml.
  • 5.5. A method for analysis of hemolymph trehalose by gas chromatography is described.
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2.
  • 1.1. Specific Dynamic Action (SDA) effects of diet were investigated in the supralittoral isopod, Ligia pallasii, using defined chemical diets.
  • 2.2. “Apparent SDA”, or the total rise in metabolic rate following a meal, was resolved in animals eating a nutritionally complete chemical diet into three components: 8% mechanical costs of moving food through the gut, 40% “excitement costs” due to investigator disturbance and presence of food, and 52% SDA.
  • 3.3. Excitement costs in animals exposed to food but which chose not to eat showed non-significant variation between diets containing different levels of chemical nutrients, but were significantly less on a diet containing only cellulose and agar.
  • 4.4. SDA increased with increasing concentration of amino acids in the diet.
  • 5.5. Substitution of whole-protein casein for free amino acids in the diet had no significant SDA effect, while substitution of free amino acids in the ratio found in casein more than doubled the SDA effect.
  • 6.6. Deletion of alanine from the diet caused no significant effect on SDA, while deletion of phenylalanine caused a highly significant elevation in SDA.
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3.
  • 1.1. An artificial diet, consisting of a dry aggregate of 59 chemical substances, was used to assess the requirements of the sea slater Ligia pallasii for vitamins, carbohydrates, fatty acids, cholesterol and minerals.
  • 2.2. Good growth and survival of L. pallasii was obtained on the diet, comparable to that on seaweeds and to that shown by a field population.
  • 3.3. No dietary requirements for vitamins, fatty acids or cholesterol were shown for periods of 40 weeks or more for L. pallasii.
  • 4.4. Carbohydrates were shown to be required by L. pallasii in its diet, in the order: starch, lactose > maltose, glucose > sucrose, cellulose.
  • 5.5. Dietary requirements for minerals were, in order: calcium, magnesium, phosphorus > copper, nickel, zinc > iron, manganese, sulphur > iodine, silicon.
  • 6.6. The results are discussed in relation to the role of gut bacteria in supplying required nutrients to their isopod hosts and the enhancement of this process through coprophagic behaviour.
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4.
  • 1.1. The effects of a high-fat, high-energy diet and essential plus semi-essential amino acid gavage on pup rats have been studied (60–65 animals).
  • 2.2. The activities of alanine transaminase, adenylate deaminase, glutamine synthetase and serine dehydratase have been tested in liver and muscle.
  • 3.3. Plasma was used for the estimation of proteins, urea, amino acids, glucose, lactate, 3-hydroxy-butyrate and acetoacetate.
  • 4.4. Liver and muscle glutamine synthetase activities are increased by diet and gavage administered. Hepatic serine dehydratase is inhibited by a cafeteria diet but activated by amino acid gavage. Adenylate deaminase is inhibited by diet and gavage in the liver, but gavage does not affect this enzyme activity in muscle. Liver alanine transaminase is increased by the diet; in the muscle, cafeteria diet and amino acid gavage showed the highest values for this enzyme.
  • 5.5. In the plasma, the increase in lactate produced by the diet is inhibited by the amino acids provided. Cafeteria-fed pups showed lower urea levels and higher 3-hydroxybutyrate concentrations in the plasma.
  • 6.6. Intracellular glucose is diminished by cafeteria diet. In contrast, the blood cell amino acid concentration increases with diet and gavage supplied.
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5.
  • 1.1. Adult male and female cockroaches (Blattella germanica) were maintained on a positive nitrogen balance diet (66% protein) containing various levels of allopurinol (0–3%) to determine the effects of allopurinol on urate synthesis and storage.
  • 2.2. Each insect was injected with [14C]hypoxanthine and after 1 week was analyzed for whole-body hypoxanthine, xanthine and urate radiolabel.
  • 3.3. There was a general trend of decreased whole-body radiolabel retention, radiolabeled body urates and total-body urate content in both sexes with increasing amounts of dietary allopurinol.
  • 4.4. Virgin female adults were allowed to feed on diets containing 0, 25 and 66% protein plus 0.1% allopurinol and were injected with [14C]xanthine.
  • 5.5. After 1 week radiolabel content in the whole-body xanthine and urate pools was determined.
  • 6.6. Females on the 0% protein diets contained less radiolabel in the whole-body and body urates than those on either 25 or 66% protein diets.
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6.
  • 1.1. Adenylate cyclase activity was determined in membranes of white and brown adipose tissue (WAT and BAT, respectively) from rats fed a high-energy diet (EXP group) vs those fed a nutritionally balanced one (CON group).
  • 2.2. The isoproterenol- and guanine nucleotide-induced adenylate cyclase activity in WAT membranes of EXP rats was lower than that in CON rats.
  • 3.3. Relative adenylate cyclase activity in like treated BAT membranes was higher in EXP than in CON rats.
  • 4.4. It is concluded that feeding high-energy diets to rats induces similar post-receptor modifications of adenylate cyclase as found in genetic obese rodents.
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7.
  • 1.1. Most bird muscle spindles are supplied by only one primary afferent.
  • 2.2. Secondary afferents occur irregularly.
  • 3.3. Sensory terminals are covered by a basal lamina and a collagenous sheath.
  • 4.4. Two types of motor terminal are recognized which can be referred to specific types of intrafusal fiber.
  • 5.5. The sensory and motor innervation of bird intrafusal fibers is less understood than that of mammalian intrafusal fibers.
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8.
  • 1.1. Ration and body size effects on specific dynamic action (SDA) were investigated in the supralittoral isopod Ligia pallasii using seaweed and chemical diets.
  • 2.2. SDA increased asymptotically with ingested meal size for all diets.
  • 3.3. Body weight had a significant positive effect on SDA for only one of the six diets tested, but weak tendencies were present in the data for the other diets.
  • 4.4. SDA appeared to increase geometrically with increasing concentration of amino acids at high ration levels.
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9.
  • 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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10.
  • 1.1. Growth, survival, ammonia excretion and Specific Dynamic Action (SDA) were assessed in the supralittoral isopod Ligia pallasii eating chemical diets with differing proportions of d- and l-amino acids. Growth and survival decreased in direct proportion to increasing dietary intake of d-amino acids.
  • 2.2. Survival on diets with greater than 50% content of d-amino acids (based on total amino acids in diet) was lower than that expected based on previous work, suggesting a deleterious effect of the d-isomers.
  • 3.3. Ammonia excretion and SDA correlated negatively with increasing dietary content of d-amino acids.
  • 4.4. The general conclusion is that d-amino acids play no role in anabolic or energy metabolism in Ligia, and that poor performance at higher dietary levels of d-amino acids may relate to their interference with transport pathways for the normal l-forms.
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11.
  • 1.1. Food consumption, assimilation and passage rates of an elephant shrew, Elephantulus edwardii, on three natural diets (cockroaches, locusts and termites) and one artificial cereal diet (Pronutro) were compared.
  • 2.2. Daily food consumption varies significantly between the diets and was partly related to % assimilation, which was highest on Pronutro and cockroaches (71%) and lowest on termites (31%).
  • 3.3. Throughput times were estimated using soluble (51 Cr-EDTA) and particulate markers in the Pronutro diet. First appearance of the soluble marker (0.5 hr) was significantly earlier than for the particulate marker (1.85 hr); 50% appeared at 3.2 and 3.35 hr for the soluble and particulate markers, respectively.
  • 4.4. The distribution of particulate markers in the digestive tract showed some retention in the stomach, ileum and colon, but rapid movement through the duodenum and very little entry to the caecum.
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12.
  • 1.1. We investigated the effects of the ingestion of naturally occurring glucosinolates in rapeseed meal on growth rate, metabolic efficiency and respiratory rate in larvae of the yellow mealworm, Tenebrio molitor L.
  • 2.2. In our feeding studies, larvae were reared on one of seven different diets, including a whole ground wheat control diet and rapeseed meal from six rapeseed varieties. Dry weight gain of larvae and dry food assimilated were measured after 4 weeks of rearing, and the conversion of food into insect biomass was determined. The results may be explained by variations in the glucosinolates content of the diets.
  • 3.3. The effect of glucosinolates on food consumption, larval growth, expired carbon dioxide, oxygen uptake and respiratory quotient were studied.
  • 4.4. Glucosinolates did not reduce food assimilation or growth after 1 day of experimentation, but they caused some inhibition of respiratory exchanges and increased the RQ ratio.
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13.
  • 1.1. Mineral balance was studied in meadow voles (Microtus pennsylvanicus) maintained in the laboratory.
  • 2.2. Urine and fecal Na+ contents of voles on low-Na+ diets were comparable to those reported for other herbivore species, but urine and fecal K levels were higher.
  • 3.3. Voles approached Na+ balance (input = output) on diets with Na+ content as low as 56 ppm.
  • 4.4. There was not a clearcut hypertrophy of the adrenal-gland zona glomerulosa in voles maintained on low-Na+ diets.
  • 5.5. Plasma K content and bone water content were higher in voles maintained on high-Na + vegetation diets, suggesting expansion of extracellular fluid volume.
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14.
  • 1.1. Pyruvate dehydrogenase complex (PDC) activity was measured in several tissues of rats fed for 7 or 15 days on control, or high-sucrose or high-fat diets.
  • 2.2. Total activity in adipose tissue increased in the three groups 3–4-fold as compared with chow-fed animals in the first week. Total activity was 60% lower in rats fed the diet containing 22% corn oil for 2 weeks.
  • 3.3. Hepatic total and PDCa activities were 50–80% higher in rats fed the sucrose diet for 7 or 15 days and decreased 30–40% in those fed on the high-fat diet for 2 weeks.
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15.
  • 1.1. Responses of channel catfish (Ictalurus punctatus) swim-up fry to dietary calcium in soft (< 1 mg/1 as CaCO3) and hard (> 100 mg/1 as CaCO3) water were determined by feeding purified egg-white diets containing 0, 0.5, 1.0, or 2.0% calcium from CaCO3 for 8 weeks.
  • 2.2. Catfish fry fed the basal diet (0.03% Ca) in hard and soft water had lower whole-body ash and whole-body calcium concentrations but higher weight gain and survival than those fed calcium-supplemented diets.
  • 3.3. Fry in soft water generally had lower whole-body ash, whole-body calcium, and survival, as well as a higher incidence of spinal deformities than fry in hard water.
  • 4.4. Feeding higher levels of calcium to fry reared in soft water did not increase whole-body calcium levels or decrease spinal deformities to the levels observed for fry reared in hard water and fed supplemental calcium.
  • 5.5. These data indicate that calcium derived solely from dietary or environmental sources was not sufficient for optimum health of channel catfish fry.
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16.
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Highlights
  • •CMTM4 is associated with human spermatogenesis and sperm quality.
  • Cmtm4 knockout mouse were generated by CRISPR/Cas9 technology for male fertility research.
  • •CMTM4 is required for male fertility but not female fertility.
  • •Phenotype and quantitative proteomics of Cmtm4 KO mice reveal an association of CMTM4 with histone-to-protamine exchange, sperm motility and induction of the acrosome reaction.
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17.
  • 1.1. Eggs of wild cod, and of farmed cod fed (a) a diet supplemented with astaxanthin and (b) a diet supplemented with both astaxanthin and canthaxanthin, were analysed with respect to carotenoids.
  • 2.2. The total carotenoid contents in eggs were 0.7 ppm for wild cod and 0.5 ppm for farmed cod.
  • 3.3. Cod, having white flesh, deposit ketocarotenoids in the eggs, preferably astaxanthin.
  • 4.4. Canthaxanthin can replace astaxanthin in the eggs, but astaxanthin appears to be deposited preferentially when both carotenoids are present in the diet.
  • 5.5. The isomer distribution of (3S, 3′S):(3R, 3′S, meso):(3R, 3′R) astaxanthin in the eggs reflected the isomer composition of the diet.
  • 6.6. Echinenone, 4′-hydroxyechinenone, adonixanthin and zeaxanthin encountered in cod eggs may represent reductive metabolites of canthaxanthin and astaxanthin.
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18.
  • 1.1. The optimum pH for measurement of aspartate transcarbamylase activity in oyster tissue was determined to be 9.35 while the optimum temperature was 39.5°C.
  • 2.2. Aspartate transcarbamylase activity varied significantly over short periods of time (hr) possibly due to fluctuations in the amount of food digested.
  • 3.3. The composition of the oyster's diet also affected the levels of aspartate transcarbamylase activity in oyster tissues.
  • 4.4. Those oysters fed an egg yolk-starch diet contained significantly lower aspartate transcarbamylase activity than oysters fed an egg yolk-starch-salmon oil diet or a casein-starch-salmon oil diet.
  • 5.5. The aspartate transcarbamylase activities in oysters fed Phacedactylum tricornutum or a starch diet were not significantly different from the activities in oysters fed the egg yolk-starch diet.
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19.
  • 1.1. Administration of a carbohydrate-rich diet increased haemolymph glucose levels and glycogen concentration in hepatopancreas, mantle and muscle.
  • 2.2. Glycogen concentration in tissues decreases after 2 weeks of starvation and haemolymph glucose levels did not change significantly.
  • 3.3. However, starvation did not induce a decrease in the intrinsic synthetic capacity in tissues.
  • 4.4. Glycogen synthesis in tissues from animals fed with lettuce or a carbohydrate-rich diet, increases with increasing glucose concentration in the media.
  • 5.5. However, in mantle slices from snails adapted on a carbohydrate-rich diet, the glycogen synthetic capacity was lower than in slices from snails fed with lettuce.
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20.
  • 1.1. Changes in body composition during starvation were compared between germ-free (GF) and conventionalized (CVL) chicks in experiment 1. At 8 days of age, the GF birds were divided into two groups, i.e. GF and CVL groups. The CVL birds were inoculated with faeces from conventionally reared birds. Until 14 days of age, both birds were fed a diet ad lib, and thereafter starved for 6 days.
  • 2.2. Nitrogen loss during starvation was significantly lower in CVL birds, though the reverse was true for water loss. Fasting heat production was comparable between two environments.
  • 3.3. Influence of the gut microflora on body weight and nitrogen losses during starvation was investigated in birds prefed diets high or low in dietary protein in experiment 2.
  • 4.4. No significant effect of the gut microflora was observed in body weight and nitrogen losses. Body weight was severely reduced in birds prefed the high protein diet and nitrogen loss was lower in birds prefed the low protein diet.
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