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141.
我国北部绵羊脱毛症与锌营养状况关系的探讨   总被引:1,自引:0,他引:1  
 通过对绵羊脱毛症流行病学的调查、临床症状和病理变化的观察,以及对牧草、饮水和绵羊血浆锌状况的检测,得出绵羊脱毛症是一种自然缺锌症。本研究采用可控可溶锌玻璃丸治疗绵羊脱毛症,效果好,方法简便,不用重复多次给药,一次给丸即解决问题,且未见任何中毒及其它异常迹象。  相似文献   
142.
青菜品种锌效率特性研究   总被引:5,自引:0,他引:5  
 对6个有代表性的青菜品种吸收利用锌能力的差异进行了研究。结果表明,青菜地上部分千物质重、锌的累积吸收量可以较好地反映品种间吸收、富集锌能力的差异;在缺锌或施锌条件下,品种五月慢均有最高的干物质积累量和累积吸锌量,缺锌时的累积吸锌量与其它品种呈极显著差异,其锌利用效率较高;五月慢较大的根系活性吸收表面积与较长的根系长度,是其具有较强耐低锌能力和吸收富集锌的能力的重要生理基础之一;缺锌时,五月慢的根冠比明显减小,而矮脚黄、黑油白菜两个一般性品种的根冠比呈增加趋势。  相似文献   
143.
园艺植物锌素营养的研究   总被引:2,自引:0,他引:2  
对国内外有关锌在园艺植物上的应用 ,植物体对锌的吸收 ,锌的生理功能 ,土壤和植物体内锌与其他元素间的关系和常见园艺植物矫治缺锌症方面的研究现状进行了综述。  相似文献   
144.
载锌蒙脱石对大肠杆菌K88抗菌效果的影响   总被引:2,自引:0,他引:2  
通过阳离子交换反应合成了载锌蒙脱石(Zn*Ca-MMT&Zn*Na-MMT),X射线衍射分析显示,载锌反应前后,蒙脱石的(001)面网间距增大,表明锌是以水合阳离子形式进入蒙脱石晶格层间位置。体外抗菌试验表明,蒙脱石(Ca-MMT&Na-MMT)未显抗菌活性,而Zn*Ca-MMT和Zn*Na-MMT对大肠杆菌K88均有很强的抑制和杀灭作用,且后者的杀菌效果优于前者。  相似文献   
145.
水培结果表明,绵阳11和15号小麦耐有效锌的临界值为600ppm。在0.05—400ppm以内。幼苗生长正常,400ppm时,便出现锌中毒症状,至600ppm时,症状最严重,显症时间最早,从培养第3日起,植株开始枯萎,到第9日,焦叶指数和蔫萎指数均达三级,植株含锌量达6674ppm;而400ppm处理的,症状较轻,植株含锌量明显下降,为6185ppm。加钙处理(500ppmCa~(2+)),使症状加剧,显症提前,植株含锌量相应增高。加0.1%EDTA处理,使症状减轻,推迟显症,植株含锌量下降;在最高锌量(600ppm)加EDTA处理,较其它处理的植株,症状最轻、最迟,含锌量最低。  相似文献   
146.
Pearling is an effective method for evaluating the distribution of chemical components in wheat grain. Twelve pearling fractions (P1–P12) of wheat grain were obtained using two rice polishers for 10 cultivars (six soft red wheats and four hard white wheats) grown at two locations with different environmental conditions in Jiangsu Province, China. The results show that the effects of cultivar, location, and pearling on wheat flour phytase activity, phytate, iron, and zinc contents were all significant, with pearling having the greatest effect. All the four components showed a diminishing trend as pearling progressed from the outer layers to the inner part of wheat grain. Generally, the P2 fraction (the outer 4–8% layer of wheat grain) had the highest phytase activity and phytate and iron contents, whereas the P1 fraction (the outer 0–4% layer) ranked the highest for zinc content. Growing location had a large influence on grain phytase, phytate, and iron, but the differences between locations decreased as pearling level increased.  相似文献   
147.
A total of 720 Nile tilapia fingerlings were allocated to four treatments and used to investigate the effects of zinc oxide supported on zeolite (Z‐ZnO) on growth performance and intestinal function. The basal diet (control) was not supplemented with zinc and contained 60 mg Zn kg?1. The other three groups were added 30 mg Zn kg?1 to the basal diet, in which zinc was supplemented as Z‐ZnO, Z + ZnO (mixture of zeolite and ZnO) or ZnSO4, respectively. As compared to the control, supplemental Z‐ZnO improved (< 0.05) specific growth rate, protein efficiency ratio (PER) and survivor ratio; increased (< 0.05) villus‐height‐to‐crypt‐depth ratio and transepithelial electrical resistance; decreased (< 0.05) mucosal‐to‐serosal flux of dextran 4 kDa; and improved (< 0.05) intestinal activities of protease, amylase, lipase and alkaline phosphatase. Fish fed with Z‐ZnO had higher (< 0.05) specific growth rate and PER, and better intestinal barrier function than those fed with ZnSO4 or Z + ZnO. The zinc concentrations in whole body and vertebrae were not affected by dietary treatments. The results indicated that Z‐ZnO improved intestinal morphology, barrier function and digestive enzyme activities. Such changes in intestinal health in the presence of Z‐ZnO might contribute to its improvement in growth performance.  相似文献   
148.
The haematological (Hb, RBC, WBC) and biochemical (protein and glucose) profiles of a freshwater fish Catla catla were studied under sub-lethal toxicity of cadmium chloride for 25 days (Treatment I). In addition, the influence of zinc on cadmium toxicity was investigated for haematological and biochemical parameters (Treatment II). In both the experiments, blood haemoglobin and plasma protein level decreased in the treated fish. However, WBC, RBC and plasma glucose levels were increased in Treatment I, while Treatment II showed mixed results. In Treatment II the alterations of both haematological and biological parameters were minimal compared with Treatment I. The alterations of these parameters are discussed as non-specific biomarkers against metal toxicity in aquatic organisms.  相似文献   
149.
The concentrations of iron (Fe), copper (Cu), and zinc (Zn) were evaluated in 96 samples of the following eight fish species: Centropomus undecimalis, Caranx hippos, Scomberomorus brasiliensis, Lutjanus purpureus, Caranx crysos, Megalops atlanticus, Elops saurus, and Epinephelus itajara collected in the Atrato River Delta in the Gulf of Urabá. Three fish were caught from each of the following common fishing grounds: Bahía Candelaria, Bahía Marirrío, Bocas del Roto, and Bocas del Atrato. Fish were captured during a one-year period, with one specimen per species in each climatic period: dry, transient, and wet. The quantification was performed by microwave plasma-atomic emission spectroscopy. The highest levels of Fe and Cu were found in Caranx crysos, and highest level of Zn in Megalops atlanticus. According to the percentage of the daily value per food serving, Caranx crysos and Caranx hippos are good sources of Fe, and Caranx crysos is a good source of Cu.  相似文献   
150.
本实验选择湖北白猪IV系,35日龄断奶仔猪27窝,共236头分九组。用3×3正交设计Lg(34),检验基础日粮中添加不同水平的甲酸钙(0.1%、2%),杆菌肽锌(0.63万IU,126万IU),铜(75mg/kg、150mg/kg),其组合效应及其对断奶仔猪影响。试验由45日龄正式开始到75日龄结束。30d试验结果表明:以不加甲酸钙的第2组(添加63万IU杆菌肽锌和75mg/kg铜)的平均日增重,饲料利用率和经济效益较好。添加甲酸钙的6个组平均日增重,饲料利用率及经济效益不如1、2、3组。其中第2、3组平均日增重分别是452、449g,与NRC(1988)规定10~20kg日增重450g接近,而且比第1组(空白)提高了6.35%,5.65%,但差异不显著(P>0.05)。每千克增重饲料成本2、3组分别比第1组(2.117元)降低14.7%和11.4%,饲料利用率2、3组分别比1组(2.02)提高了15.3%,12.7%。  相似文献   
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