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1.
The influence of flight and flight duration on 13 blood parameters was studied in homing pigeons which returned after 2–22 h of flight from release sites 113–620 km away. The haematocrit value decreased from 54.4% in controls to 51.0% in the flown birds. A lowered haematocrit overproportionately improves blood flow. The plasma concentrations of glucose and l(+)-lactate did not differ between experimental and control birds. This is compatible with the idea that carbohydrates are utilized as fuel mainly in the initial phase of flight. Plasma free fatty acid levels were significantly increased during flight and triglyceride concentrations gradually decreased with progressive flight duration. These findings support the view that lipids are the main energy source during flight. Plasma uric acid concentrations were increased two- to fourfold in flown birds. Urea levels gradually rose with flight duration to 400% of controls. Plasma protein concentration was lowered in flown pigeons. These results hint to an increased protein degradation during flight. Na+, K+, Ca2+, and Mg2+ levels in the plasma of the flown pigeons were not significantly different from control values. This finding together with the urea/uric acid ratio indicates that no severe dehydration occurred in our pigeons during free-range flight.Abbreviations FA fatty acids - FFA free fatty acids  相似文献   

2.
The effects of an endurance flight on the haematocrit, the percentage of packed red blood cells per blood volume, were examined within the framework of six possible factors explaining possible changes in the haematocrit. Two approaches were adopted: (1) the haematocrit was studied in four species of passerine birds which landed on an Italian island after having crossed the Mediterranean Sea on their spring migration in a non-stop flight; (2) the haematocrit was evaluated in six individual red knots after a flight of 1, 2, 4 and 10 h in a wind tunnel and the data thus obtained compared with data on resting birds with or without food. In the four passerine species, the haematocrit decreased from 51% in fat birds to 48% in lean birds. In lean birds, the haematocrit dropped from 48% in birds with well-developed breast muscles to 36% in birds with emaciated breast muscles. In the red knots, the haematocrit was dependent on body mass in flying and resting birds. The haematocrit decreased from about 51% pre-flight to about 49% within 1 h of flight and remained at this level for up to 10 h of flight. Taking the results from the passerines and the red knots together, it seems that the haematocrit drops by a few percentage points within 1 h after the onset of flight, decreases very slowly with decreasing body mass and decreases more steeply in very lean birds having entered stage III of fasting. This indicates that dehydration is not an underlying factor in decreased haematocrit because if this were the case we would expect an increase with endurance flight. We found no effect of the presence of blood parasites on haematocrit. With the onset of flight, haemodilution may be adaptive, because it reduces blood viscosity and, thereby, energy expenditure by the heart, or it may be a sign of water conservation as an insurance against the risk of dehydration during long non-stop flights. During endurance flight, a reduction in the haematocrit may be adaptive, in that oxygen delivery capacity is adjusted to the decreased oxygen needs as body mass decreases. A decreasing haematocrit would also allow birds to reduce heart beat frequency and/or heart size, because blood viscosity decreases disproportionally with decreasing haematocrit. However, when energy stores are about to come to an end and birds increase protein breakdown, the haematocrit decreases even further, and birds probably become anaemic due to a reduced erythropoiesis.  相似文献   

3.
Adult pigeons were subjected to acute cold exposure (-25 degrees C; 30 min) after which the levels of blood glucose, blood and muscle lactate and plasma lactic dehydrogenase were measured. Partially defeathered (dorsum and pectoral regions) birds, following exposure to cold, showed marked reduction in blood glucose and blood and muscle (pectoralis) lactate. Fully plumed birds, in contrast, showed no significant reduction in body temperature or blood glucose and only moderately reduced lactate levels indicating the effectiveness of the insulative feather coat in maintaining thermal and metabolic homeostasis. The partially-defeathered pigeons exposed to cold showed a two-to-three-fold increase in plasma lactic dehydrogenase activity, which may reflect a molecular adaptation in their calorigenic response to cold.  相似文献   

4.
The effect of feeding isocaloric test diets containing 35, 45 and 55% protein, with and without inclusion of the anabolic steroid hormone, ethylestrenol, was studied in rainbow trout, Salmo gairdneri , in relation to blood chemistry. The control (no hormone) and experimental diets (hormone-supplemented), were fed for a total of 60 days, after which time all groups of fish were fed an identical commercial diet with no hormone for a further 30 days (withdrawal period). After 60 days, the body weights offish fed the 35 and 45% experimental diets were significantly greater than their respective controls, and after hormone withdrawal, increased growth was still apparent in the 35% experimental group.
No significant changes in serum amino acid nitrogen (AAN), protein, or glucose in relation to the dietary protein level, or inclusion of steroid, were observed after 30 days. Serum creatinine, however, increased with an increase in dietary protein, and was significantly higher in the 35% experimental group than the respective control. After 60 days, the most significant observation was the marked increase in serum glucose with an increase in dietary protein, but respective control and experimental values were not significantly different at this time. Following a 30-day withdrawal period, serum AAN in the 55% experimental group was significantly higher than the control, whereas serum protein, creatinine, and glucose stabilized to similar concentrations in all groups. Over the 90-day period of feeding, in both control and experimental groups, serum AAN and protein tended to increase, serum creatinine and glucose to decrease, whilst haematocrit remained constant. It is concluded that addition of ethylestrenol to trout diets has apparently little effect on serum metabolite concentrations and haematocrit, the most significant variations being related more to diet composition and duration of study.  相似文献   

5.
Haematocrit measurements and plasma protein electrophoresis were carried out in female pigeons (Columba livia) during the breeding cycle. Non-laying birds showed higher (p < 0.001) haematocrit values than those involved in courtship and mating, nest-building, incubation and feeding and brooding. Significant differences in relative percentage of various plasma protein fractions were observed as a function of breeding. Haematocrit could be a useful index to the non-laying status of pigeons like that in chickens, Gallus domesticus.  相似文献   

6.
Sources of variation in haematocrit in birds   总被引:2,自引:0,他引:2  
The validity of the haematocrit or packed cell volume as an indicator of condition in wild birds has recently been questioned. We reviewed over 300 published papers on haematocrit values for wild birds. These studies show that changes in haematocrit could be caused by a number of different natural factors that include age, sex, geographical elevation, energy expenditure, parasitism, nutrition and genetics. Haematocrit also increased with age from hatching, due to increased erythropoiesis, so that adult birds generally have greater haematocrit values than nestlings or juveniles. Haematocrit values were either independent of elevation or increased with elevation. A meta-analysis of 36 studies showed no difference in haematocrit between the sexes. Relationships between haematocrit value and both energy expenditure and parasitic infection vary between studies. In temperate climates, haematocrit tended to be higher in winter than in summer, which may be due to dehydration or increased oxygen demand caused by thermogenesis, moult or acquisition of reproductive status. Our review indicates that the use of haematocrit as a sole indicator of condition or health could lead to incorrect conclusions if natural factors that can affect haematocrit are not taken into consideration.  相似文献   

7.
目的:探讨儿童化学发光免疫分析中标本量过少时,用怎样的稀释介质以及稀释方法解决这个问题,分析不同的稀释介质产生的基质效应。方法:本实验以儿童常规筛查检测项目血清三碘甲状腺原氨酸(TT3)为例,选取血清样本30例,分别使用美国贝克曼库尔特公司UniCelDX1800Access化学发光免疫分析仪测试药盒三碘甲状腺原氨酸(TT3)配套TT3定标液s0(简称TT3S0)、0.9%氯化钠、医用蒸馏水作为稀释介质进行手工2倍(1:1)及4倍(1:3)后测定。计算稀释测定结果与原始数据的差异,观察基质效应对检测结果的影响。寻找实际工作中可运用的稀释介质和稀释倍数。结果:不同稀释组与原始值之间比较,TT3S02倍(t=-0.7937,P〉0.05)、4倍稀释(t=-0.2503,P〉0.05),以及蒸馏水2倍稀释(t=-0.2845,P〉0.05)差异均无统计学意义。而0.9%氯化钠2倍(t=-6.4686,P〈0.05)、4倍稀释(t=-3.9842,P〈0.05),以及医用蒸馏水4倍稀释(t=-1.9957,P〈0.05)差异有统计学意义。结论:三碘甲状腺原氨酸TT3S0定标液2倍,4倍稀释方法及医用蒸馏水2倍稀释方法均可以得到较为满意的结果。三碘甲状腺原氨酸(TT3)配套TT3定标液S0可用于标本2倍及4倍稀释。当定标液获取困难,蒸馏水2倍稀释同样可以运用。  相似文献   

8.
The effects of a competitive marathon race on serum biochemical and haematological parameters have been evaluated. Blood samples were obtained shortly before and immediately after the race; urine samples were also obtained before and after the race. Body weight was recorded pre- and post-race. During the race subjects consumed a total of 1.41 of either water or a dilute glucose-electrolyte solution. The average weight loss of the runners was 2.09 +/- 0.77 kg (mean +/- SD), corresponding to 2.9 +/- 0.8% of body weight. Small but significant increases in both haematocrit and haemoglobin concentration occurred; plasma volume was calculated to decrease by 4.7%. Serum potassium concentration showed no change, but the response was highly variable; serum sodium concentration increased in line with the decrease in plasma volume. In the group of subjects drinking water during the race, the pre-race plasma glucose concentration was 5.3 +/- 1.2 mmol . l-1, this was unchanged after the race (5.0 +/- 1.2 mmol . l-1). A significant increase (P less than 0.01) in the plasma glucose concentration, from 5.2 +/- 0.6 to 6.0 +/- 1.5 mmol . l-1 occurred in the group of subjects drinking the glucose-electrolyte solution. Apart from this, there were no significant differences between the two groups.  相似文献   

9.
Flounders Pleuronectes flesus with an implanted vascular catheter were exposed to a 50% dilution of the water soluble fraction (WSF) of Omani crude oil (c. 6ppm total aromatic hydrocarbons) and serial blood samples taken to determine their endocrine status (cortisol, catecholamines and thyroid hormones) and the resultant and/or causal physiological (haematological, ionoregulatory and respiratory) disturbances. This resulted in a progressive increase in plasma cortisol concentrations from 3 h onwards (rising from 18 to 51 ng ml−1 after 48-h exposure), and increased plasma glucose concentrations indicating a generalized stress response. Plasma T3 and T4 concentrations of both control and WSF-exposed groups declined progressively over the experimental period; exposure to the WSF of crude oil further depressed plasma T4 concentrations but not plasma T3 concentrations relative to those of control fish. Plasma osmolality and sodium and chloride concentrations were stable in WSF-exposed fish, however, plasma potassium concentrations were increased significantly at the 24-and 48-h sampling points. The most profound physiological disturbance in WSF-exposed fish was a dramatic decline in blood oxygen content (CvO2) (from 2–8 to 0–8 ml 100 ml−1 after 48-h exposure), which is likely to be the cause of the increased plasma noradrenaline concentrations from 3 h onwards. Increased noradrenaline is likely in turn to have been responsible for the significant increase in blood haematocrit and blood haemoglobin at the 3-h sampling point, although the dominant effect in the longer-term was a significant decline in both of these haematological parameters.  相似文献   

10.
The objective of this paper is to investigate the correlation between serum macro-element and trace element contents and bone mineral density (BMD) as well as the occurrence of osteoporosis. After the epidemiological investigation of 290 postmenopausal women from ages 45 to 65 in the Xi’an urban area, their blood was collected and serum concentrations of macro-elements, calcium, phosphonium, potassium, sodium, magnesium, and trace elements, zinc, iron, copper, and selenium were determined using atomic absorption spectrometry. Their BMD was measured by QDR-2000 dual-energy X-ray absorptiometry (DEXA). The correlation analysis between BMD and serum element contents was done with the software of SPSS 13.0. The correlation analysis of serum elements of postmenopausal women showed that there was a significant correlation between serum calcium and the other elements, and also a significant correlation between serum phosphonium and the others except serum potassium. The serum potassium content had a significant correlation with serum calcium, sodium and iron, but sodium content showed a significant correlation with the others except iron and selenium. In addition, copper had a significant correlation with the others except potassium and selenium. In correlation analysis between BMD and the elements contents, only did the potassium content show a significant positive correlation with BMD of lumbar vertebra and proximal femora. The comparison results between osteoporosis group, osteopenia group, and healthy group showed that there was no significant difference in the element contents between the groups, but there existed a tendency that potassium content increased with the rise of BMD. There exist significant correlations between the contents of serum elements such as calcium, phosphonium, sodium, potassium, magnesium, zinc, iron, copper, and selenium, but no significant differences in these elements contents between the osteoporosis group, osteopenia group, and healthy group. Serum potassium content shows a significant positive correlation with BMD, suggesting potassium may be involved in the development of osteoporosis in postmenopausal women.  相似文献   

11.
We present the case of a 79-year-old female with severe hyperkalaemia and severe prerenal insufficiency due to dehydration and nephrotoxic medications, including spironolactone. The ECG showed AV nodal rhythm and tented T waves. After treatment with fluids, insulin, polystyrene sulphonate and sodium bicarbonate, the serum potassium level and kidney function normalised. Several days later, she developed QT prolongation with giant negative T waves without signs of ischaemia.In this report, we review the effect of hyperkalaemia on cardiac ion channel function and the associated changes on the ECG. In addition, the causes and mechanisms of giant negative T waves are discussed.  相似文献   

12.
After standing for 1h, ten subjects (7 male, 3 female) assumed a supine position for a further hour. Whole body bioelectrical impedance increased progressively during the hour spent in the supine position: after 60 min supine the increase was 13(6 to 32). Blood and plasma volumes, estimated from haematocrit and haemoglobin concentration, increased by 8.0(6.7 to 12.4)% and 16.7(12.3 to 20.8)% (median(range)) respectively after 60 min supine. Serum potassium concentration had fallen after 10 min supine (4.1(0.1)mmol 1–1; mean(SEM)) relative to the standing value (4.6(0.1)mmol 1–1) and was unchanged thereafter. Serum osmolality (P=0.991) and sodium (P=1.000) and chloride (P=0.998) concentrations remained unchanged throughout the study. The fall in serum potassium concentration in the supine position does not appear to be a simple dilutional effect consequent upon increases in blood and plasma volume as there was no effect of postural change on serum sodium or chloride concentrations.  相似文献   

13.
The present experiment was carried out to investigate if levels of serum cations in broilers are modulated differently at various stages of exposure to deoxynivalenol (DON). Male broiler chicks at 7 days of age were fed a basal diet (0.27 mg of DON; 0.01 mg of zearalenone/kg), or either a low DON diet (1.68 mg of DON; 0.15 mg of zearalenone/kg) or a high DON diet (12.21 mg of DON; 1.09 mg of zearalenone/kg) produced using extracts from Fusarium graminearum cultures. Blood samples from the birds were collected during weeks 2, 4, and 5 of exposure. The high DON diet resulted in lower serum calcium levels compared to the basal diet at all the 3 sampling stages, while the low DON diet resulted in lower serum calcium levels only during weeks 2 and 5. Serum potassium levels were reduced under both the DON diets during weeks 2 and 5, while no diet-associated changes were found for serum levels of magnesium, sodium, and zinc. Under the present experimental conditions, the serum levels of calcium were consistently modulated in the broilers exposed to the DON-contaminated diets. The modulation of serum levels of potassium was, however, dependent upon the stage of exposure to DON.  相似文献   

14.
Growth-contingent alterations in potassium and sodium fluxes, ouabain binding, and potassium ion content were examined following serum stimulation of quiescent, density-inhibited chicken embryo fibroblasts. Serum stimulation resulted in very rapid 1.5- to 1.8-fold increases in ouabain-sensitive potassium influx and lesser 1.4- to 1.5-fold increases in potassium efflux and sodium influx. Potassium influx stimulation was maximal after addition of 5–20% calf serum and was unaffected by cycloheximide inhibition of protein synthesis. Reflecting the slightly greater stimulation of potassium influx versus potassium efflux, potassium ion levels were 10–15% higher in serum-stimulated compared to unstimulated cells. Specific ouabain binding levels in stimulated and unstimulated control cells were initially similar, however, by four hours after stimulation a 40–50% increase in specific ouabain binding was observed. Incubation with ouabain was found also to inhibit later serum-stimulated hexose uptake and thymidine incorporation; this blockage may be a consequence of subnormal potassium levels rather than ouabain inhibition of the serum-stimulated potassium influx.  相似文献   

15.
1. Whole body mineral content and blood parameters were monitored in dying brown trout exposed to acid (pH 4.5) and aluminium (12 mumol l-1) at low external calcium concentration (20 mumol l-1). 2. Fish surviving the treatment had elevated haematocrit, low plasma sodium levels, and low whole body sodium and potassium content. 3. Dying trout had haematocrit and plasma sodium levels similar to treatment survivors, but whole body mineral content was unaffected and moisture content increased. 4. Death was probably caused by redistribution of fluid from the extracellular compartment to the intracellular compartment.  相似文献   

16.
The changes in plasma volume, blood volume, erythrocyte indices, leucocyte indices and serum biochemical values during experimental pestes des petits ruminants (PPR) virus infection of West African dwarf goats (Fouta djallon) were investigated. There was a progressive decline of the plasma volume and serum sodium and potassium values in all the infected goats as from day 5 post-infection and this became quite marked between days 10 and 23 post-infection. The fall was severest in those animals which had diarrhoea. There were no significant changes in the chloride, bicarbonate, phosphate, urea, total protein and albumin values of the goats during the course of the diseases. Haemoconcentration and apparent polycythaemia in the early and terminal stages of the disease were associated with severe dehydration which characterized the infection. There was initial neutrophilic leucocytosis during the phase of fever followed by marked lymphopaenic leucopaenia which progressed terminally in most of the infected goats. The destructive effect of the virus on lymphocytes is suggested as a cause of lymphopaenia.  相似文献   

17.
Proximate (live mass, water, lipid, ash, non-fat organic), caloric, nitrogen, and mineral (sodium, potassium, calcium, magnesium, and iron) concentrations and total body content of individuals of 24 species of Neotropical and Paleotropical bats were determined. Mass-related, concentration patterns were found for all measured variables, except iron. Concentrations increase with size for nitrogen, calcium, and magnesium but are concave, opening upward, for sodium and potassium. These last two elements reach minimal concentrations in bats weighing about 22 and 28 g dry mass, respectively. Total body content of nitrogen and minerals was compared with amounts in similar-sized birds and tetrapodal mammals.  相似文献   

18.
Diurnal rhythm in body temperature of pigeons subjected to different experimental conditions (pinealectomized, sham-operated, melatonin-implanted, cold-exposed) was studied under a 12 h light and 12 h dark regimen. The body temperature of pigeons during photophase was higher than that during scotophase in the normal as well as every treatment group studied. Pinealectomized pigeons showed higher body temperature in the photophase as well as scotophase, than that of the normal and sham-operated birds when examined 2 or 3 weeks following the post-surgical acclimatization to 25 or 3 degrees C. However, subcutaneous implantation of melatonin pellets into pinealectomized pigeons nullified or even reversed the hyperthermic effect of pinealectomy. Exposure of pigeons to--18 degrees C for 280 min during photophase as well as scotophase, produced a marked drop in body temperature in pinealectomized, sham-operated and normal pigeons. The pinealectomized pigeons exhibited a higher body temperature than that of the sham-operated and normal ones when exposed to--18 degrees C during the photophase, but not during the scotophase. It was concluded that while the pineal is not necessary for maintaining the daily thermal rhythm in the avian body, it has a thermoregulatory role, in that it prevents rise in body temperature in warm (25 degrees C) acclimatized and chronic cold (3 degrees C) exposed birds. In acute short-term cold (--18 degrees C) exposure however, the temperature regulatory role of the pineal was not effective during the scotophase.  相似文献   

19.
Beta-adrenoceptor stimulation in vivo shifts potassium into the cells. To examine whether human erythrocytes participate in this process, we measured, along with serum or plasma potassium, the concentrations of potassium and sodium in erythrocytes. Beta-adrenoceptor stimulation was obtained by infusion of either fenoterol or hexoprenaline into 6 volunteers at rest or by endogenous amines provoked in 14 volunteers during ergometric exercise. Metabolic effects were followed at rest on serum insulin, C-peptide, and growth hormone levels, and during exercise on pH on lactate concentration in blood. The potassium concentration (mean +/- S.E.M.) dropped (p less than 0.01) in serum from 4.64 +/- 0.37 to 3.19 +/- 0.43 mmol x l-1 in the first hour at rest and in plasma from 5.70 +/- 0.93 to 4.63 +/- 0.45 in 90 sec directly after exercise. The concentration of erythrocyte sodium dropped (p less than 0.001) from 9.68 +/- 0.73 to 8.81 +/- 0.62 mmol x l-1 in cells and from 9.62 +/- 1.16 to 8.55 +/- 1.24 during exercise for 90 s, respectively. Changes in the concentration ratio of cellular sodium to potassium confirmed this sodium shift. An increased sodium transport in erythrocytes due to beta-adrenoceptor stimulation in vivo appears to complement a shift of serum potassium into the cells and may be mediated by the membrane-bound sodium, potassium ATPase.  相似文献   

20.
A total of 250 broilers in a completely randomized design selected to evaluate the effect of different levels of chromium (Cr) supplementation on performance, carcass traits and some blood parameters of heat-stressed broiler chicks. All birds were kept under heat stress temperature (33?±?3°C) and divided into five treatments groups. Each treatment consisted of five pens with 10 birds in each pen. The basal diets were supplemented with 0?ppb (control), 800?ppb Cr-L-Met (T(1)), 1,200?ppb Cr-L-Met (T(2)) or 800?ppb CrCl(3) (T(3)), and 1,200?ppb CrCl(3) (T(4)). The feed intake and body mass were measured at 10, 21, and 42?days of age. Blood samples were collected from two birds in each replicates to determine biological and hematological values at 28 and 42?days of age. There were no significant difference in mass gain and feed conversion of broilers that received Cr supplementations compared with controls. The serum glucose concentration decreased in broilers received organic chromium methionine supplements compared with other treatments groups. Slight but not significant increases were observed in serum high-density lipoprotein (HDL) concentration of treated groups than controls while the mean serum HDL concentration was significantly higher in T(2) group compared with control group. Serum low-density lipoprotein level decreased in broiler received organic Cr supplements (p?相似文献   

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