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1.
Intratracheal inoculation of 2-week old quail chicks with Aspergillus flavus spores resulted in the development of clinical signs within 24 h of infection. These were characterized by dullness, depression, anorexia, accelerated breathing, gasping and prostration leading to death. These signs continued up to 7 days followed by considerable decrease in the intensity of the symptoms as well as number of birds showing clinical signs. Mortality occurred primarily in the first week with a majority of the birds dying from 2–4 days after infection. The overall mortality during a 6-week observation period was 25%. The average body weight of the infected chicks was slightly lower than that of controls; the difference being significant at 2, 3 and 42 days post-infection. There was no appreciable difference in the mean values of haemoglobin, packed cell volume and total erythrocyte count between the infected and control chicks at any stage of infection, but total leucocyte count revealed a significant increase (p<0.05) from 3–7 days post-infection. This was due to increase in the percentage of heterophils and decrease in lymphocytes.  相似文献   

2.
Small brown planthopper, Laodelphax striatellus (Fallén) numbers usually drop sharply in the summer and revive quickly in the autumn. However, it is unclear whether and how the high temperature plays a role in this process. The effects of durations of heat exposure (33°C) on life‐history traits were examined here. Exposure of adults for 1 day during the oviposition stage led to a very low survival of nymphs. The average longevity of L. striatellus exposed for 1–31 days from oviposition was significantly longer than that of the control (27°C). Short‐term (1–5 days) heat exposure of the third instar nymphs did not significantly influence eclosion, but exposure of the fourth instar nymphs significantly increased eclosion. Lifespan from egg to adult was significantly lengthened when the third instar nymphs were exposed to heat for 2–15 days, or the fourth instar were exposed for 10 days. The preoviposition period was prolonged by heat exposure of the third or fourth instar nymphs. Short‐term heat exposure of less than 3 days of the third or fourth instar nymphs did not restrict fecundity, but when the exposure duration exceeded 5 days the total eggs per female and hatchability decreased. Exposure to high temperature increased the brachypter rate of adults. In summary, low survival and slowing development under heat exposure resulted in population decline in the summer, and the relatively high fecundity and brachypter rate led to quick revival in autumn. Temperature in the summer determines the rise and fall in numbers of L. striatellus.  相似文献   

3.
Bone-marrow smears of 175 guinea pigs aged 1-27 days and venous blood samples of 351 animals aged 1-25 days were prepared for cell counting. A significant increase of erythroblasts were found between life day 1 and 2; normoblasts increased in number synchronously with a decrease of erythroblasts after the 5th day. The percentage of the erythroid bone marrow increased from 10 to 14 during the developmental period. Beyond the perinatal period the red blood picture is characterized by the following changes: a decrease of erythrocyte count, hematocrit, hemoglobin, mean corpuscular volume, and mean corpuscular hemoglobin; a constant mean corpuscular hemoglobin concentration; an increase of the reticulocyte count. The decrease of the red cell count is compensated by a decreasing oxygen affinity attained by an important increase of 2,3-DPG. Nevertheless, the stimulus for a raising erythropoiesis remains constant which can be shown by the growing percentage of erythroid cells and reticulocytes. The difference between the human postnatal development and that of the guinea pig becomes obvious. Cell counts in dependence of body masses in postnatally growing guinea pigs, veil the perinatal finding of the increase in erythrocytes up to the 5th day and the decrease of the mean corpuscular volume after the 3rd day.  相似文献   

4.
Acute and chronic toxicity of nitrite to Clarias lazera   总被引:1,自引:0,他引:1  
The present study is an attempt to define acute (96 hr) and chronic (6-months) effects of nitrite on two different sizes of juvenile Clarias lazera. Static bioassays on acute toxicity showed median tolerance limit (TLm) for four days of 28 and 32 mg/l NO2-N for the two sizes respectively. Although nitrite is known to cause hypoxia, as a result of oxidation of haemoglobin to methemoglobin, exposure of both sizes to nitrite resulted in a decreased erythrocyte count haemoglobin content and haematocrit values. Fish exposed to nitrite responded physiologically by producing methemoglobin. A decline in serum total protein levels was recorded during acute and chronic exposure of both sizes to nitrite. This was interpreted as a generalized stress response.  相似文献   

5.
The interrelation of thyroid hormones with blood rheology and lipid profile was studied in athletes (N = 12). A decrease in blood viscosity in the athletes was caused by a lower erythrocyte rigidity index, which correlated with an increased reticulocyte count (P = 0.022), a decreased mean concentration of hemoglobin per cell (MCHC) (P = 0.006), and an increased level of thyrotropin (TTH) (P = 0.040). By multiple regression analysis, MCHC was found to be the primary correlate of the erythrocyte rigidity index (P = 0.044). The interrelation of TTH with the rigidity index was explained by a positive correlation of TTH with the reticulocyte count (P = 0.022). The level of triiodothyronine (T3) was similar in the athletes and the control subjects and negatively correlated with total cholesterol (Ch) (P = 0.033) and low-density lipoprotein cholesterol (LDL Ch) (P = 0.048), which both correlated positively with blood and plasma viscosity and erythrocyte aggregation (P < 0.05 or 0.01). Thus, the decrease in LDL Ch in the athletes, which was closely related with the higher blood and plasma fluidities and with erythrocyte aggregation, was at least partly due to the effect of T3.  相似文献   

6.
Sachar S  Saxena RK 《PloS one》2011,6(7):e22032
Single wall Carbon Nanotubes (SWCNTs) are hydrophobic and do not disperse in aqueous solvents. Acid functionalization of SWCNTs results in attachment of carboxy and sulfonate groups to carbon atoms and the resulting acid functionalized product (AF-SWCNTs) is negatively charged and disperses easily in water and buffers. In the present study, effect of AF-SWCNTs on blood erythrocytes was examined. Incubation of mouse erythrocytes with AF-SWCNTs and not with control SWCNTs, resulted in a dose and time dependent lysis of erythrocyte. Using fluorescence tagged AF-SWCNTs, binding of AF-SWCNTs with erythrocytes could be demonstrated. Confocal microscopy results indicated that AF-SWCNTs could enter the erythrocytes. Treatment with AF-SWCNTs resulted in exposure of hydrophobic patches on erythrocyte membrane that is indicative of membrane damage. A time and dose dependent increase in externalization of phosphatidylserine on erythrocyte membrane bilayer was also found. Administration of AF-SWCNTs through intravenous route resulted in a transient anemia as seen by a sharp decline in blood erythrocyte count accompanied with a significant drop in blood haemoglobin level. Administration of AF-SWCNTs through intratracheal administration also showed significant decline in RBC count while administration through other routes (gavage and intra-peritoneal) was not effective. By using a recently developed technique of a two step in vivo biotinylation of erythrocytes that enables simultaneous enumeration of young (age <10 days) and old (age>40 days) erythrocytes in mouse blood, it was found that the in vivo toxic effect of AF-SWCNTs was more pronounced on older subpopulation of erythrocytes. Subpopulation of old erythrocytes fell after treatment with AF-SWCNTs but recovered by third day after the intravenous administration of AF-SWCNTs. Taken together our results indicate that treatment with AF-SWCNTs results in acute membrane damage and eventual lysis of erythrocytes. Intravenous administration of AF-SWCNTs resulted in a transient anemia in which older erythrocytes are preferably lysed.  相似文献   

7.
以3个品种(长白猪、大白猪、松辽黑猪)16个公猪家系共计368头仔猪组成资源群体,在猪2、7和8号染色体上共选取35个微卫星标记,采用基于线性混合模型的方差组分分析方法,对影响与猪白细胞、红细胞和血小板相关的共计18项血常规指标的数量性状基因座(quantitative trait loci,QTL)进行了检测.通过似然比检验,并以自由度为2的卡方分布作为检验统计量的分布,共发现22个在P〈5%水平下显著的QTL,其中在2号染色体上有9个,分别影响白细胞总数、中性粒细胞数、平均红细胞体积、血红蛋白含量、平均红细胞血红蛋白浓度、血小板总数、平均血小板体积、血小板分布宽度和血小板压积,在7号染色体有7个,分别影响白细胞总数、中性粒细胞数、平均红细胞血红蛋白浓度、血红蛋白含量、血小板总数、平均红细胞体积和红细胞分布宽度变异,在8号染色体上有6个,分别影响中性粒细胞百分比、淋巴细胞百分比、平均红细胞血红蛋白浓度、血小板总数、血小板压积和平均红细胞体积.为尽可能地避免由于多重检验所造成的假阳性率的升高,我们采用了控制假检出率(false discovery rate,FDR)的方法来对这22个QTL进行进一步检验,发现有14个达到FDR〈5%显著水平,其中又有9个达到FDR〈1%显著水平.  相似文献   

8.
1. Wistar rats of both sexes received vanadium in drinking water in the amount of 23-29 mg/kg body weight in the form of ammonium metavanadate (AMV) for a period of 2, 4 and 8 weeks. 2. Animals treated in this way ate less food and drank less AMV solution as compared with the amount of water consumed by the controls; they suffered from diarrhoea, and owing to this the increment in body weight was reduced. 3. Vanadium decreased erythropoiesis and maturation of red blood cells, which was expressed by a reduced erythrocyte count and haemoglobin level and increased reticulocyte and polychromatophilic erythrocyte count in the peripheral blood. 4. The composition percentage of the bone marrow cells and the peripheral blood leukocyte count did not undergo noticeable changes under the influence of vanadium.  相似文献   

9.
Toshiaki Matsura 《Oecologia》1981,50(3):291-295
Summary Survival period, pattern of decrease in body weight and metabolic rate under starvation conditions were examined to clarify responses to starvation of a predatory insect, the mantis, Paratenodera angustipennis (S.). (i) The average survival period in starved condition was the shortest in the 1st instar larvae (5.4 days) and the longest in the adults (15.0 days for males, 26.7 days for females). (ii) The body weights of the 3rd and the 5th instar larvae decreased almost linearly during fasting period, whereas those of adults decreased greatly during the initial 5 days, and then exhibited little further decline until their death. (iii) The carbon dioxide production by the adult mantids in the dark condition at constant 26°C was measured by the improved Boysen-Jensen's method. There was a linear relationship between the body weight and the metabolic rate per individual on a double logarithmic scale, and the regression coefficient b was 0.806. (iv) The metabolic rate per individual was greatest at satiation, but the rate per unit weight was maximum on the 5th day after satiation when the food had been just digested completely, and both decreased with the progress of starvation. (v) Based on the above mentioned results, properties of P. angustipennis as a predator were discussed.  相似文献   

10.
The term functional validation has been used to describe situations in which fully developed behaviours require appropriate environmental support during an early sensitive period if the initial level of responsiveness is to be maintained. The primary objective of the present study was to determine if an age-related decline in responsiveness to the maternal feeding call occurred in Gallus chicks and, if so, whether or not brief exposure to the call during an early responsive period would maintain responsiveness beyond that period. A decline in responsiveness to the call was observed beyond three days of age in dark-reared chicks. Exposure to the call for 7.5 min before three days of age was adequate to maintain responsiveness at five days of age.  相似文献   

11.
Selenium (Se) deficiency causes injury of diversified tissues and cells, including livers, hearts, skeletal muscles, and erythrocytes. The aim of the present study is to explore the molecular mechanism of erythrocyte hemolysis due to Se deficiency in broilers. One hundred and eighty broilers (male/female, 1 day old) were randomly divided into two groups and fed with either a normal Se content diet (C group, 0.2 mg Se/kg) or a Se-deficient diet (ED group, 0.008 mg Se/kg) for 45 days. During the trial period of 15–30 days, biological properties such as osmotic fragility, fluidity, phospholipid components of cell membrane, adenosine triphosphatase activities, and antioxidant function of erythrocytes in broilers were examined. Moreover, the messenger RNA (mRNA) expressions of genes associated with inflammation, glycometabolism, and avian uncoupling protein (avUCP) were detected. We found that compared with the C group, hemolysis rate, degree of polarization, and microviscosity of erythrocytes were increased in broilers of the ED group. The composition of erythrocyte membrane lipids was changed. Meanwhile, the antioxidant function of erythrocytes was weakened and mRNA levels of inflammatory genes were stimulated by Se deficiency (p < 0.05). In addition, mRNA expressions of rate-limiting enzymes in glycometabolism were effected and avUCP mRNA level was downregulated (p < 0.05) in the ED group. It has been concluded from the results that oxidative stress, inflammatory response, and glycometabolism disorder lead to erythrocyte hemolysis by changing the structure and function of erythrocyte membrane in ED broilers suffered from Se deficiency.  相似文献   

12.
In order to clarify age-related changes in hematological values of normal rats after birth, blood samples from neonatal F344 rats of both sexes were examined periodically during the period from 0 to 40 days postpartum. The erythrocyte count (RBC) increased with time after birth as a function of age. In contrast, the reticulocyte count (Retics) continuously decreased with time after birth. Hemoglobin (Hb), hematocrit (Ht), and the mean corpuscular hemoglobin concentration (MCHC) tended to decrease after birth until weaning (about 21 days postpartum), but they began to increase after weaning. Mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) also gradually decreased after birth until weaning, but they were unchanged thereafter. The platelet count (PLT) gradually increased after birth and reached a plateau at weaning. Microscopic examination of blood smears revealed that erythrocytes at birth had characteristic morphological features such as anisocytosis, polychromasia, basophilic stippling, Howell-Jolly body, and erythroblastosis. These characteristic features, however, disappeared by 30 days after birth. The total leukocyte count (WBC) gradually increased with time after birth, due to an increase in the number of lymphocytes. The lymphocyte count started to rapidly increase within several days after birth and the increase continued thereafter. Other differential leukocyte counts also showed various characteristic patterns of changes during the neonatal period. There were no apparent differences between males and females in these changes in hematological values.  相似文献   

13.
The time-effect relationship of dicentrics and cells containing unstable chromosome abnormalities (Cu cells) was studied in peripheral lymphocytes of 40 blood samples from 23 patients suffering from seminoma during a time period of 0-1720 days after radiation therapy. Nine patients were studied before treatment. Since the half-time for the disappearance of damaged cells from circulating blood is an increasing function of post-exposure time it can only be expressed as a differential value. The present model discriminates between the mean lifetime m for lymphocytes and a parameter q which is the differential half-time for the decline of damaged cells immediately after exposure (t = 0). If the time t is short compared with m the decline is asymptotically time-hyperbolic rather than exponential and can be described by q only. According to recalculations of previous data, comprising 30 years post exposure, m approximates 10 years. Differential half-times can be derived for any time post treatment within the analysed time period for the decline of the incidence of dicentrics. For example at the end of therapy (t = 0) the differential half-time was calculated to be 0.4 years and at 1720 days post exposure 3.6 years resulted. The corresponding values for the percentage of Cu cells cannot be derived for t = 0; at 1720 days 3.9 years resulted.  相似文献   

14.
Although the vertebrate stress response is essential for survival, frequent or prolonged stress responses can result in chronic physiological stress, which is associated with a suite of conditions that can impair survivorship and reproductive output. Anthropogenic habitat fragmentation and degradation are potential stressors of free-living vertebrates, and in theory could result in chronic stress. To address this issue, we compared haematological indicators of stress and condition in agile antechinus (Antechinus agilis) populations in 30 forest fragments and 30 undisturbed, continuous forest sites (pseudofragments) in south-eastern Australia over 2 years. In peripheral blood, the total leucocyte count was lower and the neutrophil/lymphocyte ratio and percentage of eosinophils in the total leucocyte population was higher in fragment than pseudofragment populations, indicating that fragment populations were probably experiencing higher levels of stress hormone-mediated and/or parasite infection-related chronic physiological stress. The total erythrocyte count and haematocrit were higher and mean erythrocyte haemoglobin content was lower in fragment than pseudofragment populations. This suggests that fragment populations showed possible signs of regenerative anaemia, a syndrome associated with elevated hypothalamus–pituitary–adrenal axis mediated stress. However, mean erythrocyte volume was also lower in fragments, and red blood cell distribution width did not differ between the study populations, findings which were not consistent with this diagnosis. Whole blood and mean cell haemoglobin concentrations were similar in fragment and pseudofragment populations. We suggest that where anthropogenic activity results in habitat fragmentation and degradation, chronic stress could contribute to a decline in agile antechinus populations. The broader implication is that chronic stress could be both symptomatic of, and contributing to, decline of some vertebrate populations in anthropogenically fragmented and degraded habitats.  相似文献   

15.
Objective: Previous studies have suggested that obesity enhances the inflammatory response, producing macromolecules involved in the induction and/or maintenance of increased erythrocyte aggregation. The objectives of this study were to evaluate the correlation between inflammation markers, erythrocyte adhesiveness/aggregation, and the degree of obesity and to assess phosphatidylserine expression on erythrocyte surface membrane of obese vs. nonobese individuals. Research Methods and Procedures: Erythrocyte adhesiveness/aggregation in the peripheral venous blood was evaluated by using a new biomarker, phosphatidylserine expression was assessed by means of flow cytometry, and markers of inflammation were measured in 65 subjects: 30 obese [body mass index (BMI) = 41 ± 7.7 kg/m2] and 35 nonobese (BMI = 24 ± 2.7 kg/m2) individuals. Pearson correlations and Student's t test were performed. Results: A highly significant difference was noted in the degree of erythrocyte adhesiveness/aggregation and markers of inflammation between the study groups. BMI correlated with erythrocyte adhesiveness/aggregation (r = 0.42, p = 0.001), erythrocyte sedimentation rate (r = 0.42, p = 0.001), high‐sensitive C‐reactive protein (r = 0.55, p < 10?4), fibrinogen (r = 0.37, p = 0.004), and white blood cell count (r = 0.45, p < 10?4). The degree of erythrocyte adhesiveness/aggregation correlated with erythrocyte sedimentation rate (r = 0.5, p < 10?4), high‐sensitive C‐reactive protein (r = 0.56, p < 10?4), fibrinogen (r = 0.54, p < 10?4), and white blood cell count (r = 0.32, p = 0.01). Discussion: Our results suggest that obesity‐related erythrocyte adhesiveness/aggregation is probably mediated through increased concentrations of adhesive macromolecules in the circulation and not necessarily through hyperlipidemia or phosphatidylserine exposure on erythrocyte's membrane.  相似文献   

16.
The present work, studied the effect of 0, 1,000, 1,500 and 2,000 mg of garlic powder/kg dry ration for Piaractus mesopotamicus (Osteichthyes: Characidae), weighting 73.6 +/- 39.4 g and measuring 15.0 +/- 2.7 cm, fed for a period of 15, 30 and 45 days. Fifteen days after treatment with 1,000 and 2,000 mg of garlic/kg dry ration, significant reduction of Anacanthorus penilabiatus (Monogenea: Dactylogyridae) in the gills was related. Nevertheless, the addition of garlic to the ration caused significant increase in the erythrocyte number and in the thrombocyte percentage in the circulating blood. However, a decrease in the lymphocyte percentage was also observed. After 45 days, fish fed with garlic showed significant increase in the erythrocyte number, leucocyte, haemoglobin rate, hematocrit and thrombocyte.  相似文献   

17.
-DOPA (-3,4-Dihydroxyphenylalanine) is one of the most highly active allelochemicals. -DOPA is exuded from the roots of velvetbean [Mucuna pruriens (L.) DC. var. utilis] into soil, and causes growth inhibition of other species. In order to highly clarify the phytotoxic mechanism of -DOPA, its effect on 32 species was surveyed, and absorption, translocation and metabolism in a tolerant species, barnyardgrass (Echinochloa crus-galli L.), and susceptible species, lettuce (Lactuca sativa L. cv. Great lakes 366), were examined at the germination stage. The species tested showed distinctly different responses to -DOPA, with root elongation being more suppressed than that of shoots. Barnyardgrass was 77-fold more tolerant than lettuce based on the GR50 values determined 5 days after treatment. Absorption of -DOPA in barnyardgrass and lettuce increased continuously during a 5 day exposure period, however,barnyardgrass absorbed a larger amount of -DOPA than lettuce. The translocation of radioactivity derived from 14C--DOPA to shoots was greater in lettuce than in barnyardgrass 3 and 5 days after treatment. Although the -DOPA absorbed was metabolized in the roots of both species, the percentage of radioactive 14C--DOPA increased in lettuce continuously but decreased in barnyardgrass over 5 days. In lettuce roots, a continuous increase of -DOPA but not other metabolites was observed. However, the concentration of -DOPA was higher in barnyardgrass roots compared with lettuce roots throughout the exposure period. These results suggest that -DOPA itself is the active form, and the species-selective phytotoxicity of -DOPA is at least partly due to metabolism and not due to absorption or translocation.  相似文献   

18.
Summary Chicken eggs incubated for 12–18 days were catheterized via the allantoic artery and temperature was monitored simultaneously using a probe positioned in the allantoic fluid adjacent to the embryo. Fluid temperature (referred to as egg temperature), arterial pressure and heart rate were measured following abrupt exposure to a lower environmental temperature (ca., 2628°C). Egg temperature and heart rate diminished exponentially: The rate of decline of egg temperature approximated Newton's law of cooling, the rate coefficient being 0.0220.025°C/min·°C throughout the incubation period from 12 to 18 days. The half time of temperature response of the egg was 2728 min. The response was much slower than that of fertile unincubated eggs (Kaplan et al. 1978), suggesting that the extraembryonic fluids act as a thermal buffer in embryonated eggs. The heart rate response in older embryos (1718 days) changed in the same manner as egg temperature, while in younger embryos (1216 days) the heart rate diminished more quickly than the change in egg temperature. During development the cardiac pacing of the embryo suggests that it becomes resistive to mild cold stress. The systolic pressure remained almost unchanged or even increased during one hour of exposure as the embryo developed, while the diastolic pressure decreased steadily after exposure irrespective of development. The 18-day-old embryos retained the systolic pressure unaltered during 3-hour exposure. In embryos 34 days prior to hatching the functional capacity of the heart apparently allows continued pumping even after prolonged exposure to low environmental temperature. Symbols and Abbreviations: See definitions at the end of the Materials and methods section  相似文献   

19.
Summary The shivering, body temperature, and metabolic response to stable and decreasing ambient temperature were measured in winter acclimatized Black-capped Chickadees,Parus atricapillus. Shivering activity, measured by duration and amplitude of bursts, increased curvilinearly from thermoneutral temperatures of 27°C down to 0°C. This parabolic shivering response may be a major component of the curvilinear response of metabolism to decreasing ambient temperature.Birds exposed to 0°C exhibited metabolism 32–45% lower than predicted for a 12-g homeotherm and body temperatures 10°C below the pre-experimental nocturnal body temperature. This hypothermia was not the result of a breakdown in thermoregulation, but was a controlled effort serving to reduce overnight energy expenditure. It is suggested that (1) hypothermia was achieved by decreased shivering by pectoral muscles during exposure to decreasing ambient temperatures, (2) the rate of body temperature decline was moderated by intermittent and reduced bursts during the cooling period, and (3) body temperature was maintained at a particular level during exposure to a stable low ambient temperature by intense bursts lasting one to three minutes.The physiology of hypothermia in chickadees is similar to torpor; however, chickadees did not arouse to a normal diurnal body temperature in the laboratory, and their hypothermia was not induced by inanition or prolonged exposure to cold, as reported for other species capable of torpor.  相似文献   

20.
Absidiosis was produced experimentally in rabbits by intravenous inoculation of 1.4×105 spores of Absidia corymbifera. Infected rabbits exhibited a rise in body temperature, anorexia, dullness, listlessness, diarrhoea, occasional blindness, convulsions and death in some cases. Mortality occurred mainly between 6 to 9 days post infection (DPI) and overall mortality was 50 per cent during the three week observation period. No significant difference was observed in erythrocytic indices viz., Hb, PCV, TEC in control and infected rabbits. However, erythrocyte sedimentation rate was considerably increased in the infected rabbits. A state of leucocytosis was observed in the infected rabbits, which was due to increase in the relative percentage of neutrophils and decrease in lymphocytes. There was a significant increase in blood urea nitrogen concentrations of infected rabbits from 3 to 14 DPI as compared to controls, but serum creatinine values were not significantly altered at any stage of infection. The cause of death was attributed to kidney failure and uraemia in infected rabbits. The rabbit was found to be a suitable model for the study of absidiosis.  相似文献   

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