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1.
Because vanadium (V) is easily reduced to a cationic form within plant cells, data from resin-extraction of soil were analysed for evidence of interactions between V and the resin-extractable concentrations of magnesium (Mg) and calcium (Ca) on soybean seed yield. Three varieties, 9091, 9061 and 704, were grown over a 3-year period in a corn–soybean–wheat rotation. Surface soil samples (0–15 cm) were extracted with ion-exchange resins, extracts were analysed by inductively coupled plasma methods (ICP), and the results were regressed against seed yield using SAS PROC STEPWISE analysis using forward selection, backward elimination and maximum R2 routines. The seed yield of each variety showed a correlation with a unique set of resin-extractable concentrations of V, phosphorus (P), Mg and Ca, and the V:(V + P), Mg:(Mg + Ca), Mg:(Mg + 1000 V) and Ca:(Ca + 1000 V) ratios. Variety 9091 was most sensitive to the Mg:(Mg + Ca) ratio. Variety 9061 was most sensitive to extractable V and to the V:(V + P) ratio. Variety 704 was sensitive to extractable P, V and Ca and the Mg:(Mg + 1000 V) ratio. For variety 9091, Mg fertilization (not currently practised) may be an economical practice, whereas P fertilization of 704 may not be economical. Each regression technique varied slightly in identification of important factors in seed yield. Concentrations and ratios of resin-extractable elements in soil provide insights into optimal genotype selection and possible management alternatives for a given soil. 相似文献
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Noorin Zafar Mukhtar A. Khan 《Journal of animal physiology and animal nutrition》2019,103(6):1959-1968
Seven isonitrogenous (400 g/kg crude protein) and isocaloric (17.89 kJ/g gross energy) purified diets (casein‐gelatin based) with different concentrations of calcium (0, 1, 2, 3, 4, 5 and 6 g/kg) supplemented with calcium lactate at the levels of 0, 5.4, 10.8, 16.3, 21.8, 27.27 and 32.73 g/kg were prepared and fed for 12 weeks to triplicate groups of Heteropneustes fossilis (7.46 ± 0.03 g) to determine the optimum dietary calcium requirement. Analysed values of calcium in the diets were 2.41, 3.82, 4.56, 5.99, 6.71, 7.40 and 8.19 g/kg, respectively. Absolute weight gain, specific growth rate, protein retention efficiency, protein gain and feed conversion ratio of fish fed diets with increasing levels of dietary calcium improved up to 5.99 g/kg and then levelled off. Whole‐body protein, moisture and ash contents improved up to 5.99 g/kg dietary calcium and stabilized thereafter. However, whole‐body fat exhibited reverse pattern and decreased with incremental levels of dietary calcium up to 5.99 g/kg. Whole‐body and vertebrae mineralization was also significantly affected (p < .05) by the increasing dietary calcium levels. Alkaline phosphatase activity improved significantly (p < .05) up to 6.71 g/kg, and no change was recorded beyond this level. Serum calcium and phosphorus concentrations were not influenced (p > .05) by dietary calcium levels. The Ca–P ratio remained static in the whole body, vertebrae and serum. Broken‐line regression analysis of data obtained on growth, mineralization and serum ALP activity against increasing levels of dietary calcium reflected the optimum calcium requirement between 5.77–6.81 g/kg diet. 相似文献
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选用纯种野公猪与杜洛克母猪的杂交后代含50%野猪血缘的42日龄杂交野猪36头,随机分成9组,试验为双因子3水平(3×3)析因安排分组,完全随机区组设计,每个因子3个水平,共9个处理。结果显示,不同磷水平与钙磷比例对各处理组的平均日耗料量、平均日增重、料重比差异均不显著(P>0.05)。不同钙磷比例水平下对血清钙的影响差异极显著(P<0.01),日粮磷和钙磷比例互作效应对血清钙影响差异极显著(P<0.01)。不同日粮钙磷比例对血清磷水平差异显著(P<0.05),日粮磷和钙磷比例互作效应对血清磷影响显著(P<0.05);0.4%的日粮磷水平与0.6%的磷水平对血清AKP活性影响差异极显著(P<0.01)。 相似文献
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外源钙对干旱胁迫下木豆种苗生理特性的影响 总被引:1,自引:0,他引:1
通过模拟贵州岩溶地区土壤富钙的生境(CK和50 mmol·L-1 CaCl2),以岩溶地区常见饲用灌木木豆(Cajanus cajan)为材料,研究外源钙对干旱胁迫(CK,5%,10%,20% PEG-6000)下木豆种子的萌发率、保护性酶活性(SOD,POD,CAT)及可溶性蛋白质和GSH含量的变化。结果表明:木豆种子萌发随着干旱胁迫的增强而呈显著线性下降趋势(P<0.01),施加外源钙对其无显著影响;随着干旱胁迫的增强保护酶SOD和POD成指数关系,CAT成负二次关系;施加外源钙能显著提高低浓度干旱胁迫下木豆种子SOD和POD活性;可溶性蛋白质和GSH含量随着干旱胁迫的增强呈现指数和二次曲线关系,施加外源钙显著提高了木豆种子可溶性蛋白质和GSH含量(P<0.05)。表明外源钙的施加能缓解木豆种子受到的干旱伤害,提高木豆苗期抗旱性。 相似文献
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Feeding Solanum glaucophyllum to preparturient multiparous cows prevents postparturient hypocalcemia 下载免费PDF全文
Junichiro Ishii Akifumi Uramoto Yoshikazu Nagao Hisaya Goto 《Animal Science Journal》2015,86(10):869-877
Solanum glaucophyllum (SG) contains 1,25‐dihydroxyvitamin D3 (1,25‐(OH)2D3) glycosides. We investigated the effect of SG on hypocalcemia in cows. Serum levels of 1,25‐(OH)2D3, total calcium and phosphorus dose‐relatedly increased after feeding with SG, while serum magnesium and chloride levels fell (P < 0.05). We also performed an ethylenediaminetetraacetic acid (EDTA) infusion to induce artificial hypocalcemia. Cows that had been fed 4.0 mg/kg body weight of SG daily for 2 weeks had a higher serum concentration of total calcium at the end of EDTA infusion than those not fed SG (P < 0.05). In a field trial, multiparous cows were assigned to one of four groups: (1) no SG, (2) 1.3 g or (3) 2.6 g of SG daily from 14 days before the estimated calving day until 3 days after calving, or (4) a single feed of 35.75 g SG at 3 days before the estimated calving day. The concentrations of serum total calcium after the calving in each treatment group were (1) 7.4, (2) 7.9, (3) 8.0 and (4) 8.9 mg/dL and higher for (4) than for (1) (P < 0.05). The data suggests that feeding a high dose of SG before the calving may maintain higher concentrations of serum calcium after the calving. 相似文献
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将患有蹄病的牛按病情严重程度分三级,在每级中各选出12头,并将36头随机分成4组,每组共9头。第1组为对照组,第2组每头牛日粮中加35%石粉18g,第3组每头牛日粮中加硫酸锌1.2g,第4组每头牛日粮中同时加35%石粉18g和硫酸锌1.2g。同样护理,每星期对试验牛群进行修蹄及常规治疗。经过1个月的治疗第1组治愈1头,有效3头,无效5头;第2组治愈2头,有效6头,无效1头;第3组治愈3头,有效4头,无效2头;第4组治愈7头,有效2头,无效0头。卡方检测除第2、3两组差异不显著外,其他各组之间差异显著。说明在日粮中适量提高钙和锌对奶牛蹄病有良好的预防和治疗作用。 相似文献