铬对热应激下蛋鸡脾组织结构的影响

将处于热应激条件下的 192只 35周龄新罗曼褐壳蛋鸡随机分成 6组 ,分别饲喂不添加铬的玉米 -豆粕型基础日粮和添加 10、2 0、30、4 0、5 0 mg/ kg葡萄糖耐量因子 (glucose tolerance factor,GTF)的试验日粮 5 2 d。取出器官组织固定后 ,制作石蜡切片 ,HE染色 ,光镜观察。观察可见 ,添加 2 0 mg/ kg GTF组蛋鸡脾白髓中脾小结体积增大 ,生发中心明显 ;空肠管壁出现集合淋巴小结。添加 30、4 0 mg/ kg GTF组蛋鸡脾白髓动脉周围淋巴鞘增厚 ;椭球数量增多 ,体积增大。结果显示 :给热应激下蛋鸡补充有机铬 (GTF) ,免疫器官 (脾 )的组织结构发生明显变化 ,可缓解热应激反应 ,增强机体免疫功能     

Effects of supplemental nanoparticle trivalent chromium on the nutrient utilization,growth performance and serum traits of broilers

The aim of this study was to investigate the effect of dietary supplementation of nanoparticle trivalent chromium on nutrient utilization, growth performance and serum traits of broilers. This study included two trials. In trial 1, 32 three‐week‐old broilers were divided into four groups: the control, chromium chloride (CrCl₃), chromium picolinate (CrPic) and nanoparticle chromium picolinate (NanoCrPic). Chromium was added at a 1200 μg/kg level to evaluate the nutrient and chromium utilization. In trial 2, 160 one‐day‐old broilers were randomly divided into four groups as in trial 1, with four replicates. The results of trial 1 indicated that the chromium utilization is as follows: NanoCrPic > CrPic > CrCl₃ and control groups, with significant differences between groups (p < 0.05). Crude fat utilization in CrCl₃ group was lower than in that the control group (p < 0.05). The results of trial 2 indicated that feed intake of 4–5 weeks showed better result in the CrCl₃ group than that in the CrPic group (p < 0.05). The results of serum traits indicated that the LDL‐cholesterol in the NanoCrPic groups was lower than that in the CrPic group (p < 0.05). The NanoCrpic and CrPic groups showed significantly increased serum chromium concentration when compared with the control and CrCl₃ groups; the triglyceride level in the CrCl₃ group was lower than that in the CrPic group (p < 0.05). This study concluded that compared with CrPic, NanoCrpic supplementation could increase chromium utilization and lower the serum LDL‐cholesterol of broilers.     

不同浓度铬盐饲料对鲤生长和血浆生化指标的影响

用添加不同浓度铬的饲料投喂1龄和3月龄鲤Cyprinus carpio L.，观察其生长状况。结果表明，用添加铬0.5mg/kg的饲料饲养1龄鲤65d，其相对生长率高于对照组13.79%，饲料转化率提高21.83%。饲养3月龄鲤40d期间，用添加铬1mg/kg的饲料饲养的鲤与对照组相比，其体重有增加趋势；用添加铬2mg/kg和5mg/kg饲料饲养的鲁分别在30、20d内生长缓慢，40、30d出现负生长；用含铬10mg/kg饲料饲养的鲤停止生长。总之，在饲料中添加低剂量的铬可以促进鲤的生长，添加高剂量的铬则抑制鲤的生长。对投喂含0.5mg/kg铬饲料组的鲤测定血清离子、Na^ 、K^ 、Ca^2 、Mg^2 、PO3^-4、Cl^-含量和血糖浓度，结果与对照鱼无显著差异；测定其血清总蛋白、甘油三脂、谷丙转氨酶活性，均低于对照鱼，但仍在正常值范围内；对鲤的鳃、肝、肾组织进行病理检查，均未发现异常变化。本实验表明，饲料中添加铬饲养鲤的安全浓度应低于2mg/kg。     

Assessment of Disturbances in Growth and Physiology of Carrot Caused by Chromium Stress

To see the deleterious effects of excess chromium (Cr) on carrot (Daucus carota L.) the cv. ‘Pusa Keshari’ was grown in refined sand under controlled glasshouse conditions with a complete nutrient solution (without Cr) for 48 days. On the 49th day, pots with two plants each were separated into three sets. One set served as a control. In each of the other two sets, Cr was supplied as dichromate at 0.1 and 0.5 mM to the basal nutrient solution. At 0.5 mM Cr toxicity symptoms appeared at d 52 (4 days after Cr supply) as reduction in growth and leaf size and loss of turgor. Old leaves became chlorotic and wilted. Chlorosis intensified and turned necrotic in another few days. These symptoms spread to next upper leaf. The development of chlorosis in leaves was delayed in plants receiving 0.1 mM Cr. At excess Cr (0.5 mM) in carrot, the biomass, concentration of chlorophylls a and b, iron (Fe), sulfur (S), and phosphorus (P) in shoots, and activity of catalase (CAT) in leaves decreased whereas the concentration of Cr and the activity of peroxidase (POX), superoxide dismutase (SOD), ribonuclease (RNAse), and acid phosphatase (A P) in leaves increased.     

GENOTYPIC DIFFERENCES IN NUTRIENT UPTAKE AND ACCUMULATION IN RICE UNDER CHROMIUM STRESS

The effect of chromium (Cr) on the uptake, distribution and accumulation of nine nutrient elements was studied in two rice genotypes, Xiushui 113 and Dan K5. The effect on elemental concentrations and accumulations varied with Cr level, nutrient element, genotype and plant part. Maximum nutrient accumulation occurred at 10 μM Cr, while the minimum occurred at 100 μM Cr, indicating best plant growth at the 10 μM level. It may be assumed that low Cr level enhance plant growth. The correlation between the concentrations of Cr and nine elements differed among plant parts, but Cr accumulation was significantly and negatively correlated with the accumulation of each element, suggesting that increasing Cr level may create nutrient deficiencies or imbalance in rice.     

Critical Toxic Ranges of Chromium in Spinach Plants and in Soil

ABSTRACT

Long-term irrigation with untreated industrial sewage effluents causes accumulation of high concentrations of chromium (Cr) and other heavy metals in soil and subsequently in crop plants (especially leafy vegetables), which can be phytotoxic to plants and/or a health hazard to animals and humans. Greenhouse experiments were conducted to determine the effects of Cr application on the growth of spinach (Spinacia oleracia L.) and to develop critical toxic ranges of Cr in plants and in soil. The study involved growing of spinach variety ‘Punjab Green’ in a greenhouse on silty clay loam and sandy soils equilibrated with different levels of applied Cr (0, 1.25, 2.5, 5, 10, 20, 40, 80, 160, and 320 mg Cr kg^{? 1} soil). Plants were harvested at: three growth stages 45, 60, and 90 days after sowing (DAS). Critical toxic ranges were estimated by regressing and plotting data on ammoniumbicarbonate-diethylenetriaminepenta-acetic acid (AB-DTPA) extractable Cr in soil or Cr concentration in plants versus dry-matter yield (DMY) of spinach at the three growth stages. Toxic ranges, i.e., slightly toxic (80%–90%), moderately toxic (70%–80%), and extremely toxic (< 70%) in terms of DMY relative to the attainable maximum DMY, were established for both soils and for plants at all three growth stages. There was no germination of spinach with applied Cr at 320 mg Cr kg^{? 1} rate in silty clay loam soil and at 40 mg Cr kg^{? 1} rate in sandy soil due to Cr toxicity. Roots accumulated more Cr in comparison with shoots. Chromium concentrations of 0.47–1.93 mg Cr kg^{? 1} soil in silty clay loam soil, 0.13–0.94 mg Cr kg^{? 1} soil in sandy soil, 1.08–5.40 mg Cr kg^{? 1} plant DM in silty clay loam soil and 0.54–11.7 mg Cr kg^{? 1} plant DM in sandy soil were found to be toxic. The critical toxicity ranges of Cr thus established in this study could help in demarcating Cr toxicity in soils and in plants such as spinach and other leafy vegetables due to irrigation of soils with untreated sewage water contaminated with chromium.     

电解法去除土壤中铬污染试验初报

受铬矿尾矿库污水不合理排放的影响,铬金属在下游水源和土壤中超标现象较为严重。为治理铬污染,开展了电解法去除土壤中铬污染试验,结果表明：采用磷酸盐缓冲液作为电解质,在铬污染土壤两端加上低压直流电场,使铬污染土壤在电解液磷酸盐缓冲液介子中以离子态产生迁移,即以三价或六价铬向电极方向移动,从而使土壤中的离子态铬在阴极端得到富集,土壤中的金属铬得到有效去除。     

Tolerance of rice plants to trace metals

Abstract

The tolerance of rice (Oryza sativa L. C.V. Earlirose) to various trace metal excesses was tested to determine if high levels of the trace metals found in some field‐grown plants were at toxicity levels. In one experiment, levels of 2200 μg Zn/g dry weight, 44 μg Cu/g dry weight, 4400 μg Mn/g dry weight, and 32 μg Pb/g dry weight in shoots of young plants had no adverse effects on vegetative yields. A level of 3160μgZn/ g dry weight decreased yields about 40% (P = . 05). In another test 51 μg Cu/g dry weight or 94 μg Pb/g dry weight did not decrease vegetative yields. Boron supplied at 10^‐3 MH₃BO₃ not only caused no toxicity but resulted in only 144 μg B/g dry weight in shoots. Root levels of Zn were about equal to those in shoots; Mn levels were lower in roots than in shoots (1/4 to 1/10); B levels were generally low in both shoots and roots with roots 1/10 that of shoots; Cu levels were higher in roots than in shoots. Rice was tolerant of a high level of Cr. The tolerance of rice to high levels of some trace metals in these experiments may be related to high P levels in plants.     

Effect of High Nickel and Chromium Background Levels in Serpentine Soil on Their Accumulation in Organs of a Perennial Plant

The effect of high concentrations of nickel (Ni) and chromium (Cr) in alkaline serpentine Fluvisol (FL 1) on their uptake by grapevine as a perennial plant was compared to their accumulation on alkaline Fluvisol (FL 2) and an acid Cambisol (CM). The FL 1 revealed high pseudo total Ni (900–1737 mg kg^?1) and Cr (263–775 mg kg^?1) concentrations, whereas those in FL 2 and CM were low. Diethylenetriaminepentaacetic acid (DTPA)–extractable Ni was greatest in FL 1; DTPA‐extractable Cr was less than the detection limit. Concentrations of metals in grapevines revealed the pattern root > leaves > shoots > grapes. At FL 1, high Ni and Cr concentrations (40.7–68.8; 23.3–41.3 mg kg^?1) in roots were measured. In grapes, these concentrations were low (Ni 0.4–0.9; Cr 0.1–0.6 mg kg^?1), whereas those on FL 1 do not differ significantly from others, indicating that alkaline serpentine soils may be used for grapevine or other perennial plant growth.     

铬(Ⅵ)和菲单一及复合污染对土壤微生物酶活性的影响

采集上海青浦现代农业园区稻田土壤,通过室内模拟试验,研究铬(Ⅵ)和菲单一及复合暴露对土壤微生物过氧化氢酶和脱氢酶活性的影响及交互作用方式。铬(Ⅵ)和菲单一及复合暴露对两种酶活性的影响表现出明显的浓度-效应关系,整体上随污染物浓度升高,酶活性降低,但低浓度菲对过氧化氢酶表现出略微激活效应。以暴露第7 d为评价终点,铬(Ⅵ)暴露对土壤过氧化氢酶EC10和EC20分别为203.61、471.48 mg·kg-1,菲暴露对土壤过氧化氢酶EC10和EC20分别为299.89 mg·kg-1和大于800.00 mg·kg-1,复合暴露对土壤过氧化氢酶EC10和EC20分别为116.14、349.28 mg·kg-1;铬(Ⅵ)暴露对土壤脱氢酶EC10和EC20都小于50.00 mg·kg-1,菲暴露对土壤脱氢酶EC10和EC20分别为113.63、223.49 mg·kg-1,复合暴露对土壤脱氢酶EC10和EC20都小于100.00 mg·kg-1。表明脱氢酶比过氧化氢酶更加敏感。采用酶活性净变量法评价交互作用方式,结果表明铬(Ⅵ)和菲复合污染对土壤微生物过氧化氢酶和脱氢酶的交互作用方式均表现为拮抗作用。