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通过在公鸡日粮中添加不同水平的亚硒酸钠,研究硒在公鸡心肌组织中的沉积量和对其组织结构功能的影响,以期为亚硒酸钠在禽类生产中的应用提供参考依据。试验选取80只体重接近、健康无疾病的海兰白成年公鸡,随机分成4组,每组20只,分别在日粮中添加0、0.3、0.6和1.0 mg/kg的亚硒酸钠。试验结束时,采集心组织样本,测定硒含量,并通过HE染色观察组织细胞结构。结果表明,公鸡心肌组织中硒含量随日粮硒含量的增加而升高。由此得出,公鸡心肌组织的硒含量随着日粮硒水平的增加而逐渐升高,高硒日粮对心肌组织的结构有一定影响,但由于硒在心肌组织中的沉积能力与其他组织相比较差,因此影响并不明显。 相似文献
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蛋氨酸硒对肉用仙居鸡生长性能、硒存留率和胴体特性的影响 总被引:5,自引:0,他引:5
采用饲养试验、代谢试验、屠宰测定等方法 ,研究在基础日粮中添加不同剂量蛋氨酸硒对肉用仙居鸡生长性能和胴体特性的影响。结果表明 ,在基础日粮中分别添加 0 .1,0 .15 ,0 .2和 0 .2 5mg/kgSe水平的蛋氨酸硒比对照组 (添加 0 .15mg/kgSe水平的亚硒酸钠 )体增重分别增加了 9.5 4 % ,12 .30 % ,9.0 7%和 8.0 4 % (P <0 .0 5 ) ;饲料转化率分别提高了 7.35 % ,9.4 5 % ,9.19%和 8.4 0 % (P <0 .0 5 ) ;硒存留率分别提高 2 9.92 % ,2 6 .4 2 % ,19.88%和 19.6 4 %(P <0 .0 5 ) ;蛋氨酸硒对鸡的胴体特性无显著影响 相似文献
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YANG Ju-qing LUO Qiu-jiang YANG Kai-lun ZHANG Guo-qing WANG Xiao XIE Peng-gui ZHANG Ji-rong 《中国畜牧兽医》2015,42(8):2048-2057
This experiment objective was to study the Fe, Cu, Mn, Zn, Se five kinds of trace element contents, distribution characteristics and mutual relations in the soil-grass-water (stream) in Yili pastoral area of Xinjiang, to evaluate the trace elements nutritional-ecologic environment of Yili summer pasture in Xinjiang.At the altitudinal belt of 1400 to 2999 m of the summer pasture of the Karajon grassland (South slope) and Tangbula grassland (North slope) of Yili, Xinjiang, the samples of soil (n=75), herbage (n=75), stream water (n=75) were collected according to the altitude, to determine their contents of Fe, Cu, Mn, Zn and Se for evaluating the nutritional-ecologic environment of trace elements of Yili summer pasture.The results showed that the contents of Fe, Cu, Mn, Zn in the soil of summer pasture on average were 15 418.4, 32.6, 474.5 and 115.8 mg/kg, respectively;And 446.0, 7.8, 85.7 and 41.9 mg/kg, respectively in forage;The correlation (R2) of the contents of Fe, Cu, Mn and Zn between soil and forage were 0.43, 0.82, 0.47 and 0.72, respectively;The changes of Fe, Cu, Mn and Zn contents in the soil and forage were not significantly related with the altitude.There were no the 4 elements mentioned above in river streams, there was no Se in the soil and forage, and there was infinitesimal of Se in the river streams.It was concluded that in Yili summer pasture there were excessive Fe, suitable Zn and Mn, insufficient Cu, and more insufficient Se. 相似文献
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A. Brandt‐Kjelsen E. Govasmark A. Haug B. Salbu 《Journal of animal physiology and animal nutrition》2014,98(3):547-558
Inorganic selenium (Se) in the form of selenite is applied to livestock to avoid Se deficiency. Selenite is, however, an artificial Se source in diets of unsupplemented chickens. It is therefore hypothesized that organic Se sources, such as Se‐enriched yeast and wheat, could be a more suitable Se supply in animal nutrition, although information on the transition of Se from organic Se sources in fast‐growing chickens is scarce. In this work, chickens were fed a low Se diet (0.27 ± 0.01 mg Se/kg, Se‐enriched yeast) until 20 days of age, after which the Se concentration was increased to maximum concentration allowed by the poultry industry in Europe (0.5 p.p.m. Se). At the same time, a daily contribution of carrier‐free 75Se tracer from labelled wheat was administered from day 20 to 27. The chickens showed S and Se homeostasis, as the concentration of S and Se in liver, blood or kidney remained about constant, and steady state of S and Se in the other organs was reached 1 day after the diet shift. The uptake of 75Se was readily seen in all organs. After 1 week, the depuration of the 75Se tracer was followed, and biological half‐lives and retention in individual organs were determined. The shortest biological half‐lives were observed in major metabolic organs, the liver, kidney and pancreas with half‐lives close to 4 days. There was a significant (p < 0.05) uptake in lung, brain and muscle that reached steady state when the administration of 75Se was terminated. The half‐life of 75Se in heart was 9 days and 7 days in blood. The longest half‐lives were observed in muscle (12 days), brain and lungs (13 days). All half‐lives were shorter than in Se deplete animals. 相似文献
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本研究以半年生翠云草盆栽为试验材料,研究不同遮荫处理对翠云草叶色变化的影响。试验设置全光照R0(透光率100%NS)、一层遮荫R1(38%NS)、二层遮荫R2(20%NS)、三层遮荫R3(16%NS)和四层遮荫R4(10%NS)共5个处理。处理3个月后,比较叶片中叶绿素a、叶绿素b、叶绿素a+b、叶绿素a/b、类胡萝卜素、花色素苷、苯丙氨酸解氨酶及可溶性糖含量变化。结果显示,叶绿素含量在3层遮荫处理下最高,叶片表现出特殊的蓝绿色;全光照下,叶绿素含量和花色素苷含量均最低,而类胡萝卜素含量最高,说明叶片受到强光胁迫,是类胡萝卜素而不是花色素苷取代了那部分被破坏的叶绿素,因此叶片表现出红色。方差分析表明,不同遮荫处理对翠云草叶片中叶绿素含量影响极显著,对花色素苷含量影响显著,而对类胡萝卜素含量影响不显著。掌握翠云草叶色在不同遮荫条件下的变化规律,有助于在园林中根据景观需要进行合理配置,创造别具特色的园林植物景观。 相似文献
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以水稻为主的种植系统对土壤有机质状况的影响 总被引:1,自引:1,他引:1
XIAO Yong-Lan ZHANG Yang-Zhu HU Rui-Zhi HUANG Yun-Xiang ZHOU Qing YUAN Zheng-Ping YANG Dong-Ping SHU Li 《土壤圈》1997,7(4):349-354
A long-term simulation experiment was carried out to study the effect of rice-based cropping system, green manure and ground-water level on soil organic matter. Soil organic matter content increased when upland soil was puddled and cropped under submerged conditions. Among all treatments, soil organic matter contents in the treatments of rice-rice-flooded fallow in winter (WF) were the highest, those in the treatments of rice-rice-astragalus (WG) came the second, and those in the treatments of rice-rice-rape (WR) were the lowest. At the same rate of green manure application, the degrees of organo-mineral complexing in soils of treatments WG and WR were higher than those of treatment WF. After 9-year rice cultivation, the state of combination of humus in heavy fraction varied with treatments. The relative content of loosely bonded humus decreased in the order of WR > WG > WF, and it correlated significantly with Se availability. 相似文献