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62.
Hrubec TC Smith SA Robertson JL 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2001,30(1):8-15
Hybrid striped bass (Morone chrysops X Morone saxatilis ) are an important aquaculture species yet there are few diagnostic tools available to assess their health. Hematology and clinical chemistry analyses are not used extensively in fish medicine due to the lack of reference intervals for various fish species, and because factors such as age can affect blood values. There is little published information regarding age-related changes in blood values of juvenile fish. It is important to evaluate juvenile fish, as this is the time they are raised in aquaculture settings. Determining age-related changes in the blood values of fishes would further develop clinical pathology as a diagnostic tool, enhancing both fish medicine and the aquaculture industry. The results of standard hematology and clinical chemistry analysis were evaluated in juvenile hybrid striped bass at 4, 6, 9, 15, and 19 months of age. Values for PCV and RBC indices were significantly lower, and plasma protein concentration was significantly higher in younger fish. Total WBC and lymphocyte counts were significantly higher in fish at 6 and 9 months of age, while neutrophil and monocyte counts were higher at 6, 9, and 15 months. Eosinophil counts were significantly higher in 9-month-old fish. The majority of hematologic values fell within previously established reference intervals, indicating that only slight modification to the intervals is necessary for evaluating hematologic results of hybrid striped bass at different ages. The following analytes deviated sufficiently from adult reference intervals to warrant separate reference values: plasma protein concentration at 4 months, WBC and lymphocyte counts at 15 and 19 months, and thrombocyte-like-cells at 9 months of age. Values for most biochemical analytes were significantly different among age groups except for creatinine and potassium concentrations. Comparisons with reference intervals were not made for biochemical analytes, because established reference intervals were not available. Age-related changes in hematologic and biochemical values of striped bass were similar to those reported for rainbow trout and mammals. 相似文献
63.
Sakamoto K Lewbart GA Smith TM 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2001,30(2):50-52
Abstract: Blood samples were collected from 29 juvenile red pacu ( Piaractus brachypomus ), ornamental freshwater fish, to establish baseline blood chemistry values. Mean (minimum-maximum) values, obtained by automated bichromatic analysis and ion selective electrode analysis, were as follows: sodium, 150.4 (146–159) mmol/L; potassium, 3.93 (2.7–5.0) mmol/L; chloride, 138.7 (128–150) mmol/L; total CO2 , 7.5 (6–10) mmol/L; albumin, 0.86 (0.5–1.0) g/dL; lactate dehydrogenase, 237.8 (65–692) IU/L; aspartate aminotransferase, 49.1 (0–125) IU/L; creatinine, 0.31 (0.2–0.4) mg/dL; calcium, 10.80 (9.5–12.5) mg/dL; anion gap, 6.89 (1.2–12.5) mmol/L; and phosphorus, 7.29 (4.1–8.9) mg/dL. 相似文献
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The activity levels of succinate dehydrogenase (SDH) and glucose‐6‐phosphate dehydrogenase (G6PD) were assessed in various tissues of Cyprinus carpio var communis which had been exposed to lethal concentrations of group‐II pyrethroids (deltamethrin, cypermethrin, fenvalerate and fluvalinate) for a period of 72 h. The results indicated a steady decrease in SDH activity with a concomitant increase in G6PD activity. The decreased SDH activity indicated inhibition of SDH at mitochondrial level and the increased G6PD activity an enhancement of an alternative pathway of carbohydrate metabolism, viz the hexose monophosphate shunt (HMP) or pentose phosphate pathway as a biochemical adaptation to overcome the toxic stress. © 2001 Society of Chemical Industry 相似文献
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北京地区西瓜枯萎病生理小种分化研究 总被引:3,自引:0,他引:3
对在北京大兴、顺义、通县等西瓜主产区采集,经单孢分离得到的8个西瓜枯萎病菌株进行了生理小种分化研究。应用国际通用的3个鉴别寄主SugarBaby、charlestonGray、calhourGray和国内京欣1号、苏蜜1号2个品种,采用全国协作组统一的苗期抗病鉴定方法,进行人工接种鉴定。结果表明北京地区西瓜枯萎病菌株均系同一生理型,为西瓜枯萎病生理小种1号。 相似文献
68.
Simon R. Leather 《Integrated Pest Management Reviews》1996,1(3):163-180
The ecological implications of insect resistance in conifers are rarely discussed. It is however a fairly straightforward plant-insect interaction and should be treated as such, making use of the increasing amount of information in this field. Work on tree breeding is usually carried out by silviculturalists who, not surprisingly, rarely consider the insect component of the environment in which the treess are growing. In all fairness, it must be stated that many entomologists, fail to consider the plant component of the interaction. Clonal forestry will almost certainly result in the loss of genetic variability. The use of clonal material has already been cited as a possible source for the diminution of the resistance against pests and diseases and if particular resistance mechanisms against forest pests are sought in the future the reduction in genetic material caused by clonal selection could have serious consequences. The ethics of clonal forestry have been questioned as have the ethics of biotechnological advances in the area of recombinant DNA molecules. The potential of both these techniques should be publicized and brought to the attention of the general public and the scientific community at large and evaluated. To improve our forest environment and to protect the environment as a whole, entomologists, geneticists, physiologists and silviculturalists must work together to produce better trees that require little, if any, chemical aid, be it insecticides, herbicides, fungicides or fertilizers. An increasing awareness of the environmental problems generated by large-scale insecticide applications to forest plantations, coupled with an increasingly chemophobic work-force and the difficulty in obtaining pesticide registration for use in forest environments, means that the forest industry world-wide must look to the use of integrated control measures with more diligence than has been shown in the past. Many recent outbreaks of pests and diseases have been linked with particular seed origins of tree crops. Host plant resistance as part of a suite of other proposed integrated control tools is thus an obvious candidate for development. Despite this, scientists concerned with tree improvement continue to select largely for silvicultural traits rather than for resistance to pests and disease. The different avenues open to plant breeders are examined and the potential of breeding trees resistant to insect attack highlighted. Using resistant trees as part of an integrated pest management system has five very important properties. Firstly, there is no additional pest control cost to the grower, secondly, it operates at all levels of insect incidence and not just when the pest is at high population levels, thirdly, it reduces the insect population cumulatively, fourthly it avoids toxic residues and environmental pollution and, finally, it usually interacts well with the other integrated pest management strategies in existence. 相似文献
69.
M. Angeles Achon Marion Pinner Vicente Medina George P. Lomonossoff 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(7):697-705
Two isolates of maize dwarf mosaic virus (MDMV-Sp and MDMV-Spl) obtained from maize in the northeast of Spain were studied. Both isolates induced similar reactions on 6 sorghum cultivars, johnsongrass and oat (cv. Clintland), with the exception of MDMV-Sp which produced a different reaction on one sorghum cultivar. Thirty-three grass species were tested as possible hosts (16 previously untested) and 18 were found to be susceptible. Among those, eight were previously unidentified hosts for MDMV:Aegilops ovata, A. ventricosa, Avena barbata, Bromus alopecurus, B. diandrus, B. fasciculatus, Echinaria capitata andLolium rigidum. Both isolates were transmitted from maize to maize nonpersistently byRhopalosiphum maidis, R. padi, Schizaphis graminum andSitobium avenae. The virus was not seed-transmitted in Mo17 and B73 maize inbred lines. Pinwheels, scrolls and short curved laminated aggregates were observed in the cytoplasm of maize cells infected by MDMV-Sp or MDMV-Sp1. In addition, laminated aggregates were observed in cells infected by MDMV-Sp1. 相似文献
70.
本文首次报导应用赤眼蜂蛹作为替代食料人工饲养尼氏钝绥螨。日食蛹量,幼螨为0.18头,产卵前期成螨达1.18头,而产卵期成螨则为0.95头左右。在25℃饲养条件下,每雌产卵达45粒,卵历期48小时,孵化率近92%,幼螨存活率88%,成螨雌性占55%,雌成螨寿命25天。用赤眼蜂蛹连代饲养的尼氏钝绥螨在桔园释放,对柑桔全爪螨具有明显的控制作用。 相似文献