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1.
  • 1.1. The effects of ovine prolactin on sodium and water transport across the intestine of 9-day old cockerels were studied by an in vitro everted gut sac technique and by an in vivo balance technique.
  • 2.2. Prolactin was found to reduce sodium and water transport across the jejunum and the rectum. AVP was ineffective.
  • 3.3. Plasma sodium levels tended to decrease in prolactin treated birds.
  • 4.4. It is suggested that the action of prolactin on intestinal salt and water transport is important in maintaining electrolyte homeostasis.
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2.
  • 1.1. The effects of Parathyroid Hormone and Calcitonin on the concentrations of ionised calcium, total calcium and phosphorus in the plasma of laying hens with and without a calcifying egg in the oviduct, were studied.
  • 2.2. Parathyroid Hormone led to an increase in the plasma calcium activity in both groups of hens, but in non-egg calcifying birds this was preceded by a transient reduction in activity.
  • 3.3. Calcitonin reduced the plasma calcium activity in non-egg calcifying birds but not in egg calcifying birds.
  • 4.4. The significance of these effects in relation to the availability of bone calcium for shell production is discussed.
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3.
  • 1.1. Seasonal variation in total lipids was examined in several body components of the turtle Sternotherus odoratus.
  • 2.2. Carcass fat stores in both sexes were depleted during winter. Additionally, a decline in carcass lipids was associated with increases in gonadal mass.
  • 3.3. Concentrations of liver lipids were maximal during August and minimal during winter.
  • 4.4. Males showed little seasonal change in plasma lipid levels, whereas females had seasonal peaks temporally associated with ovarian development and carcass fat storage.
  • 5.5. Ovarian concentrations of lipids were minimal after nesting and increased during fall.
  • 6.6. Results suggest that S. odoratus uses stored fats both for reproduction and maintenance during winter.
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4.
  • 1.1. Plasma glucose, non-esterified fatty acid, triglyceride, cholesterol and lactate concentrations were measured during 90 min treadmill exercise at a work intensity of 55–60% maximum.
  • 2.2. After 90 min exercise plasma glucose fell by 35% whilst the non-esterified fatty acid concentration rose to as much as 3–4 times resting.
  • 3.3. Exercise had no significant effect on plasma cholesterol, triglyceride or lactate concentrations.
  • 4.4. The findings indicate a progressive increase in fat utilization during prolonged exercise. Possible hormonal mechanisms underlying exercise-induced changes in lipid and carbohydrate metabolism are discussed.
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5.
  • 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%.
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6.
  • 1.1. Preheparin plasma from mice, but not rats or man, contains high levels of phospholipase A and lysophospholipase activities which are distinct from lecithin:cholesterol acyltransferase (LCAT).
  • 2.2. Neither the phospholipase A nor the lysophospholipase activities in preheparin plasma are inhibited by incubation in the presence of protamine sulphate or high salt concentrations.
  • 3.3. When mouse plasma is incubated in the presence of an antiserum specific for rat hepatic triacylglycerol lipase (HTGL), the phospholipase activities are abolished.
  • 4.4. These observations suggest that the phospholipase activities are attributable to the action of HTGL, which, in the mouse appears to be a freely circulating enzyme, whereas for other species this enzyme only appears in the blood following administration of heparin.
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7.
  • 1.1. Aspects of ruminant-like metabolism were examined in the hyrax Procavia capensis.
  • 2.2. High concentrations of volatile fatty acids occurred in the cardiac stomach with a predominance of acetic and lactic acids.
  • 3.3. Acetic (69%), propionic (22%) and butyric (8%) acids occurred in highest concentrations in the proximal caecum, with appreciable amounts in the proximal colon, distal caecum and appendices.
  • 4.4. The depot fat contained high proportions of unsaturated C18 (linoleic and linolenic) acids.
  • 5.5. The glucose level in the plasma was within the range established for non-ruminant herbivores.
  • 6.6. The possibility of silage-like fermentation occurring in the cardiac stomach is discussed.
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8.
  • 1.1. Seasonal changes in the plasma prolactin level of the migratory Canada goose breeding in the Canadian subarctic region (Fort Churchill, Manitoba) and wintering in the southern USA (Swan Lake Refuge, Missouri) were studied.
  • 2.2. Peak prolactin level was observed in geese collected at Missouri in October, immediately after Fall migration (Fall postmigratory period). This was significantly higher than that in September (Fall premigratory period), July (moulting period) and March (Spring premigratory period).
  • 3.3. Prolactin levels in May (Spring postmigratory period) and June (incubating period) did not differ significantly from that of any other period.
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9.
  • 1.1. Plasma concentrations of urea, uric acid and total lipid were compared in pre- and late-fast breeding and moulting macaroni penguins (Eudyptes chrysolophus) to test the hypothesis that birds exhaust their lipid reserves and initiate marked protein utilisation towards the end of natural fasts.
  • 2.2. Male and female macaroni penguins fasted for a minimum of 29–32 days and 20 days during the breeding and moult fasts, and the difference in body weight over the sample period (reflecting body weight loss) was 31–34% and 41–47%, respectively.
  • 3.3. There was no significant increase in plasma urea or uric acid at the end of either fast, nor any decrease in plasma lipid concentrations compared to pre-fast birds.
  • 4.4. These results suggest that macaroni penguins continue to rely mainly on lipid reserves during the later stages of natural fasts. This is consistent with post-fast body composition data for other small penguin species.
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10.
  • 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.
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11.
  • 1.1. Serum retinol and total cholesterol concentrations were determined in several species of nonhuman primates fed semipurified diets. Two species of Old World and three species of New World nonhuman primates were examined.
  • 2.2. Retinol levels were significantly lower (up to four-fold) in the serum of the smaller New World than the larger Old World animals and the difference could not be explained by differences in dietary make-up.
  • 3.3. Cholesterol levels were not different between the groups but differed within a species when type of dietary fat was altered.
  • 4.4. Differences in circulating levels of retinol may reflect differences in levels of retinol binding protein between the groups.
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12.
  • 1.1. Fifteen values were determined in blood samples from six buzzards (Buteo buteo) and six eagle owls (Bubo bubo) over the 24 hr of the day.
  • 2.2. Glucose, urea, uric acid, triglyceride and calcium values showed diurnal rhythms in both species. Their respective patterns of diurnal variation were compared.
  • 3.3. Phosphorus, cholesterol and cholinesterase levels underwent circadian rhythms only in the buzzards. Albumin/globulin and amylase exhibited diurnal variations exclusively in the eagle owls.
  • 4.4. Glutamatic oxaloacetic transaminase, albumin, globulin, total protein and creatinine concentrations did not show diurnal rhythms in either of the species.
  • 5.5. Blood values of the different parameters were studied on the basis of the ranges described in birds.
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13.
  • 1.1. Lipid concentrations and lecithin:cholesterol acyltransferase (LCAT) activity in the plasma Tropidurus torquatos were remarkably variable.
  • 2.2. Both lipid levels and LCAT activity were highest for lizards collected during the early rainy season (March–April) than during other seasons, and were higher for females than for males.
  • 3.3. Plasma lipid levels and LCAT activity were significantly and inversely correlated with body weight (age) of male lizards, this being associated with an apparent change to an herbivorous diet in older males.
  • 4.4. During prolonged fasting, plasma lipid levels and lecithin:cholesterol acyltransfer (LCAT) and hepatic phospholipids were markedly reduced.
  • 5.5. LCAT activity in plasma of fasted and non-fated lizards was significantly correlated with the molar proportion of PC to UC, suggesting that the apparent low LCAT in plasma of fasted lizards is partly due to depletion of PC in the lipoprotein substrates.
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14.
  • 1.1. The effects of photoperiod and pinealectomy on plasma corticoid levels in the goldfish (Carassius auratus) were examined.
  • 2.2. Plasma corticoid levels differed in goldfish maintained under different photoperiod regimes, but this response varied seasonally.
  • 3.3. Pinealectomy altered the effects of photoperiod on plasma corticoid levels but this effect varied with season.
  • 4.4. Plasma corticoid levels were correlated with ovarian activity. The effects of photoperiod on plasma corticoid levels appear to be related to the influence of light on reproduction.
  • 5.5. The alteration of plasma corticoid levels in pinealectomized fish may be due to the role this organ plays in mediating photoperiod effects on gonadal activity.
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15.
  • 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.
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16.
  • 1.1. Cholesterol feeding for 4 weeks of female and male rabbits of two inbred strains increased plasma cholesterol concentrations by about 11 and 48 mmole/I in the hypo- and hyperresponsive strain, respectively.
  • 2.2. On the low-cholesterol pre-experimental diet, the hyporesponsive animals had significantly higher plasma HDL (high density protein) cholesterol levels than hyperresponders.
  • 3.3. In both strains, cholesterol feeding caused elevations of cholesterol in all lipoprotein classes, the difference between the hypo- and hyperresponsive strains in essence only being observed in the VLDL (very low density lipoprotein) fraction.
  • 4.4. Basal plasma total arylesterase activity was significantly higher in the hypo- than in the hyperresponsive rabbits.
  • 5.5. Dietary cholesterol caused an increase in plasma esterase activity in both strains.
  • 6.6. We suggest that in rabbits a low plasma arylesterase activity and a low concentration of HDL cholesterol are associated with an increased sensitivity to dietary cholesterol.
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17.
  • 1.1. Compositional analysis of plasma membranes from rats fed nutritionally adequate diets different in fatty acid composition establishes that fundamentally different dietary fat intake results in alteration in structural lipid composition of plasma membranes in brain, liver and the intestinal mucosa.
  • 2.2. Dietary differences in fatty acid intake altered the fatty acyl tail composition of plasma membrane phospholipids in brain, liver and intestinal mucosa.
  • 3.3. Diet altered the phospholipid profile observed in brain synaptosomal and liver plasma membrane.
  • 4.4. Feeding high vs low polyunsaturated to saturated fat diets for 7 days altered the fatty acid composition of phosphatidylcholine, phosphatidylethanolamine, sphingomyelin and mono-glucosylceramide isolated from plasma membrane of the intestinal mucosa
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18.
  • 1.1. Changes in urine and plasma concentrations (sodium, potassium, magnesium, calcium and total osmotic) and urine production were determined in fish exposed to various concentrations of an ionically active substance, sodium chloride, and a non-electrolyte, mannitol, as well as freshwater.
  • 2.2. Responses occurred for the most part over a short crisis period preceeding establishment of new stable conditions.
  • 3.3. It was shown that plasma homeostasis was not maintained in response to changing ion-osmotic and osmotic gradients.
  • 4.4. Urinary osmotic and ionic concentrations were unaffected and urine production was shown to be inversely related to the external concentration.
  • 5.5. It is suggested that ionic shifts between body compartments are an important aspect of ion-osmotic adaptation.
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19.
  • 1.1. Some effects of restricting feed intake for 96 or 168 hr were determined in male Nubian goats.
  • 2.2. Goats restricted for 96 hr lost 11.6% of their body weight, and goats restricted for 168 hr lost 19.8%.
  • 3.3. Feed restriction for up to 168 hr did not produce significant effects on the heart rate, respiratory rate or rectal temperature.
  • 4.4. Haemoglobin concentration, packed cell volume and erythrocyte number were all decreased by feed restriction. There was also a tendency towards eosinopenia and lymphopenia.
  • 5.5. Feed restriction for 96 or 168 hr raised the plasma activity of aspartate transaminase, and did not affect significantly cholinesterase activity. Plasma amine oxidase activity was significantly reduced in goats restricted for 168 hr.
  • 6.6. Feed restriction produced significant increases in the blood or plasma concentrations of lactate. pyruvate, non-esterified fatty acids, cholesterol, ketone bodies and bilirubin.
  • 7.7. Significant decreases were found in the concentrations of total protein and calcium.
  • 8.8. No significant changes were observed in the plasma concentrations of glucose, sodium or potassium.
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20.
  • 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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