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51.
《Communications in Soil Science and Plant Analysis》2012,43(19):2504-2511
To study the impact of variable potassium (K) on biomass, economic yield, and role of K in groundnut (Arachis hypogeae L.) metabolism, plants were grown in refined sand at different levels of K, ranging from 0.5 to 16 mM. The concentration of K increased with increase in supply in all parts of groundnut. Both low (<4 mM) and excess (>4 mM) K increased the activity of peroxidase, ATPase, and acid phosphatase and decreased the concentration of chlorophyll in leaves significantly. Low (<4 mM) and excess (>4 mM) concentrations of K inhibited pod and kernel (seed) formation in groundnut. Potassium stress (both low and excess) deteriorated the quality of groundnut seed by decreasing the concentrations of starch, protein, and oil and increasing that of sugars in seeds. The activities of certain enzymes also altered in K stress in leaves and seeds of groundnut. 相似文献
52.
Hideki ASAI Noboru HAYASHI Naoharu TAKAI Yoshihisa YOSHIMURA Yutaka NAKAMURA Hiroomi YOKOTA Kazumi KITA 《Animal Science Journal》2005,76(1):51-54
In the present study, the daily excretion of potassium (K) in urine (urinary K(UK)) was estimated from a 6 h urine sample using urinary creatinine (UC) as the index substance. All urine was collected from six pregnant Holstein cows at 6 h intervals for 24 h on 3 days of the 4th, 2nd and final week before the expected date of parturition. In total, 72 6 h urine samples were obtained. Daily UC excretion (mg/day per kg bodyweight (BW)) was almost the same for the three sampling days. Daily UC excretion varied among cows from 22.1 to 24.3 mg/day per kg BW with a mean of 22.8 mg/day per kg BW with no significant difference. Thus, daily UC excretion was confirmed to be constant throughout the prepartum period with no differences among individuals. The concentration ratios of K to creatinine ((UK mg/dL)/(UC mg/dL) (UK/UC)) correlated strongly to the hourly K excretions (mg/h per kg BW) (r = 0.952, P < 0.01) in the 6 h urine samples. The differences in the UK/UC ratio between sampling periods were not significant within each cow. Therefore, daily UK excretion (mg/day) can be estimated using the equation: daily UK excretion (mg/day) = daily UC excretion (mg/day per kg BW) × BW (kg) × 6 h urine sample UK/UC, where daily UC excretion can be a given value. 相似文献
53.
Effects of feeding and animal performance on nitrogen, phosphorus and potassium excretion by Holstein cows 总被引:1,自引:0,他引:1
Hideki KOJIMA Shin-ichi KUME Kazuhisa NONAKA Tomoko OSHITA Takaharu KOZAKAI Hiroyuki HIROOKA 《Animal Science Journal》2005,76(2):139-145
Thirty‐four Holstein dry cows and 16 lactating cows were used in balance trials to identify the effects of feeding and animal performance on nitrogen (N), phosphorus (P) and potassium (K) excretion by dairy cows, and to develop prediction models for these excreta. Orchard grass silage, corn silage, alfalfa silage or timothy hay were offered to dry cows. Orchard grass silage or alfalfa silage, and concentrates were offered to lactating cows. In the statistical analysis, the independent variables were bodyweight (kg), dry matter (DM) intake (kg/day), milk yield (for lactating cows only, kg/day), water intake (free water plus water in feed, kg/day), intake (g/day) of N, P and K and dietary contents (% of DM) of crude protein, P and K. The dependent variables were N, P and K excretion (g/day) in feces and urine. In both dry and lactating cows, intake of N, P and K had large effects on corresponding excretion. The results indicated that a decrease in the intake of N, P and K could decrease the corresponding excretion. Further research by path analysis showed that K intake positively affected urinary N excretion in dry cows indirectly, through water intake and urine volume. 相似文献
54.
鄂尔多斯沙区碱湖与螺旋藻资源 总被引:15,自引:1,他引:15
通过 1 995 - 2 0 0 1年长期对内蒙古鄂尔多斯高原毛乌素沙地和库布齐沙漠的八个盐碱湖进行了实地调研 ,在其中四个碱湖中发现有四种螺旋藻 ,其中两个为新种 ,另两个为中国新记录种。作者在巴彦淖尔碱湖畔建成半封闭跑道式养殖池 ,以当地的钝顶螺旋藻为藻种 ,利用湖水养殖螺旋藻获得了成功。藻粉产量达到 6 - 8g/d· m2 ,质量通过了内蒙古卫生防疫站“食准字”检验。作者在螺旋藻养殖上的成功 ,为其产业化奠定了基础。在鄂尔多斯沙区发展螺旋藻产业有着得天独厚的优势 :众多的碱湖资源 :特有的螺旋藻资源 ;丰富的光能资源 ;不占用耕地和牧场 ;不污染环境、可持续发展等。所以 ,在鄂尔多斯沙区开发螺旋藻是继化工产业化之后的又一项新兴产业 相似文献
55.
新疆盐碱地生物改良的必要性与可行性 总被引:35,自引:7,他引:35
盐碱地资源的利用、盐渍化耕地的改良 ,在有盐碱地的地区 ,是农业生产发展的重要环节之一。新疆盐碱地总面积 2 181.4× 10 4 hm2 ,占全国盐碱土 (9913× 10 4 hm2 )面积的 2 2 .0 1% ;在 40 7.84× 10 4 hm2 耕地面积中 ,受不同程度盐化危害的面积占 30 .12 %。生物改良盐碱地 ,指利用耐盐植物直接种植 ,通过常规灌溉 ,不需要任何附加条件和设施 ,将土壤盐分控制在植物根系土层以下的土体中。新疆漫灌式种植生产有利于这种生物改良。生物改良盐碱地 ,灌溉水利用率高 ,又利于生态环境的良性循环和永久性建设。种植根系较多、较深的耐盐植物 ,土壤盐分在灌水条件 ,向下移动较深。 相似文献
56.
Aslani MR Movassaghi AR Mohri M Pedram M Abavisani A 《Veterinary research communications》2003,27(1):53-62
Eleven native sheep, 1–2 years old, of both sexes were randomly divided into two groups, 6 sheep being allocated to the experimental group and 5 serving as controls. The sheep in the experimental group were fed 80% Tribulus terrestris and 20% alfalfa hay and wheat straw, while the control sheep were given a mixture of 40% alfalfa hay and 60% wheat straw. Clinical signs of hepatogenous photosensitivity were observed from day 11, including reddening and crust formation on the muzzle, nose, ears and eyelids, depression, weight loss, icterus, conjunctivitis, and yellow discoloration of the urine. Laboratory findings on weekly samples indicated significant differences (p<0.05) in white blood cell count, total plasma protein and fibrinogen, total and direct bilirubin, blood urea nitrogen and creatinine concentrations, and aspartate aminotransferase and alkaline phosphatase activities. There were no significant differences in the packed cell volume, in the neutrophil, lymphocyte or eosinophil counts, or in the serum calcium, phosphorus, potassium, sodium or chloride concentrations. At necropsy of the experimental animals, there were various degrees of generalized icterus and the livers were swollen and discolored by bile pigment. Histopathological examination revealed varying amounts of crystalloid material in the bile ducts and renal tubules, hepatocellular degeneration, biliary fibrosis and proliferation, renal tubular necrosis and focal necrosis of cardiac muscle. 相似文献
57.
Trumel C Verwaerde P Rascol A Braun JP 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2003,32(3):140-142
Background: The Reflovet system is designed for chemical analysis of whole blood. However, plasma or serum is recommended for potassium analysis because of possible interference from RBC potassium. Because RBC potassium concentration is low in most canine erythrocytes, however, there should be little or no interference.
Objective: The objective of this study was to compare potassium results obtained in whole blood and in plasma from dogs using the Reflovet system.
Methods: Blood samples were collected from 104 dogs into lithium-heparin tubes. The potassium concentration was measured in whole blood, and subsequently the PCV was measured. Samples were centrifuged and the potassium concentration was measured in plasma. Comparisons were made using Deming's regression and Bland-Altman difference plots.
Results: There was very good correlation between results of potassium measurements in whole blood and plasma ( r = 0.93). Potassium values were moderately lower in whole blood: Potassiumblood = 0.912 × Potassium plasma + 0.119. Hemolysis had a negligible effect on the results, but the difference increased with the PCV value. In more than 90% of samples, the difference between the 2 measurements was ≤ 0.3 mmol/L.
Conclusion: There is only a negligible difference in most cases between potassium values in canine plasma and whole blood using the Reflovet system. 相似文献
Objective: The objective of this study was to compare potassium results obtained in whole blood and in plasma from dogs using the Reflovet system.
Methods: Blood samples were collected from 104 dogs into lithium-heparin tubes. The potassium concentration was measured in whole blood, and subsequently the PCV was measured. Samples were centrifuged and the potassium concentration was measured in plasma. Comparisons were made using Deming's regression and Bland-Altman difference plots.
Results: There was very good correlation between results of potassium measurements in whole blood and plasma ( r = 0.93). Potassium values were moderately lower in whole blood: Potassium
Conclusion: There is only a negligible difference in most cases between potassium values in canine plasma and whole blood using the Reflovet system. 相似文献
58.
OBJECTIVES: To investigate effects of phenobarbitone on serum activities of alanine aminotransferase, alkaline phosphatase and gamma-glutamyl transferase and concentrations of bilirubin, albumin, cholesterol and total protein in dogs. ANIMALS: Ten crossbreed experimental dogs and 10 client-owned dogs of mixed breeds treated chronically with phenobarbitone to control seizures. PROCEDURES: Experimental dogs were allocated to treatment (6 mg/kg oral phenobarbitone, n = 6) and control (no treatment, n = 4) groups in which serum biochemical tests were performed at intervals during a 3-month period. Biochemical tests were performed once on the 10 epileptic dogs. RESULTS: Phenobarbitone caused increased serum alkaline phosphatase activity but did not affect gamma-glutamyl transferase activity or bilirubin, cholesterol, albumin and total protein concentrations. Phenobarbitone had minimal effect on alanine aminotransferase activity. CONCLUSIONS: Individual dogs treated with phenobarbitone may have small increases in serum alanine aminotransferase activity and variable increases in alkaline phosphatase activity but are unlikely to have alterations in gamma-glutamyl transferase activity or bilirubin, cholesterol, albumin or total protein concentrations. 相似文献
59.
采用火焰光度法对青海省大通种牛场18头白唇鹿公鹿三项血钾指标和红细胞钾型进行了研究。结果发现:①被检青海白唇鹿公鹿的血清钾离子浓度为3.7±0.8mmol/L,全血钾离子浓度为27.4±3.0mmol/L,红细胞钾离子浓度为75.4±10.1mmol/L;②按红细胞钾离子浓度判定,全部被检青海白唇鹿公鹿的红细胞钾型为高血钾型。 相似文献
60.