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101.
钙锌对蛋用型鸡育成期体组织中矿物元素含量的影响   总被引:1,自引:0,他引:1  
试验研究了在玉米—豆饼型基础饲粮中添加不同水平锌和钙对蛋用型鸡育成期体组织中矿物元素含量的影响。结果表明,随着饲粮锌水平的提高,肝脏(P<0.01)、肾脏(P<0.05)、胰脏(P<0.01)中锌含量显著升高,而肺脏中锌含量没有显著变化(P>0.05)。饲粮高钙对组织中锌含量的影响未达到显著水平(P>0.05)。饲粮高锌使肝脏磷含量(P<0.05)、肾脏磷(P<0.01)和铜含量(P<0.05)、肺脏钙(P<0.01)和镁含量(P<0.01)显著降低。饲粮商钙使胰脏铜含量(P<0.05)显著提高,使胰脏锰含量显著降低(P<0.05)。  相似文献   
102.
以褐壳蛋鸡祖代母本种鸡为研究材料,用比浊法测定血浆极低密度脂蛋白浓度。试验结果表明,母鸡81周龄腹脂重,腹脂率,鲜肝脂肪含量的变异系数分别高达47%,39%,47%。表明这些性状在鸡群中未做过选择。血浆VLDL浓度与腹脂重,腹脂度,肝重,肝脂含量均呈正表型相关趋势。  相似文献   
103.
The distribution of copper and zinc among the soluble proteins in the liver and kidney from chronic copper-poisoned goats was examined after gel filtration of the proteins. The concentrations of copper in the liver and kidney cortex from five experimentally copper-poisoned goats were: 550–810 µg/g liver and 190–420 µg/g kidney cortex (wet weight). In general the copper-binding proteins from, both the liver and kidney samples were separated into two different fractions with approximate molecular weights (m.w.) of > 65,000 and 10,000, respectively. From the liver samples, varying amounts of copper were eluted in a fourth fraction with m.w. < 2,000. In the majority of kidney samples the dominating copper-binding protein fraction was the high molecular weight fraction. Absolute amounts of copper recovered in the metallothionein-like protein fraction were nearly the samt for all samples investigated. The distribution of zinc-binding proteins in both liver and kidney samples was nearly the same. The high molecular weight fraction dominated, and no zinc was bound to metallothionein-like proteins.  相似文献   
104.
The relationship between some skin characteristics and hemoglobin values during the growth period were statistically examined in standard male minks. Significant correlations) (P < 0.05–0.001) were found between the hemoglobin concentrations determined at 3 points during the growth period (in July, August and November) and the density and colour of underfur, and skin length, respectively. According to the study even the early hemoglobin values in July and August have a significant influence on the size and quality of the pelt. Mink kits with low hemoglobin values are liable to develop a winter fur coat with defective pigmentation and hair structure of the underfur. Anemic minks develop the most extreme stage of the pigmentation defect and these so-called cotton fur skins have little value in the fur garment industry. When these abnormal hemoglobin values are recognized at an early stage, cotton fur skins may be avoided, and larger skins of better quality may be produced.  相似文献   
105.
The efficacy of chlorhexidine digluconate was determined against some strains of collected and clinically isolated bacteria and fungi. The efficacy was evaluated either by calculating a minimum inhibitory concentration (MIC) or by efficacy trials according to the guidelines of the European Committee for Standardization. The MIC values of chlorhexidine for Staphylococcus aureus, Microsporum gypseum, Microsporum canis and Trichophyton mentagrophytes were 0.625 g/ml, 12.5 g/ml, 50 g/ml and 6.25 g/ml, respectively. The in vitro efficacy of chlorhexidine was higher against ATCC strains of S. aureus and P. aeruginosa (0.5 mg/ml for 5 min and 0.5 mg/ml for 10 min, respectively) than against clinical isolates (0.5 mg/ml for 15 min and 1 mg/ml for 10 min, respectively). The antiseptic activity of aqueous solutions of chlorhexidine against spores of Bacillus subtilis, Bacillis sfericus and Clostridium perfringens required longer contact times than against the vegetative forms. Nevertheless, 5 mg/ml of chlorhexidine in water–ethanol 20:80 v/v was totally effective against the vegetative forms or spores of these microorganisms.  相似文献   
106.
Copper and zinc are frequently added at high concentrations to pig diets as growth promoters. Livestock grazing pasture contaminated with pig slurry may, therefore, be at risk from excessive intake of these elements. High liver copper concentrations have been detected in cattle from the agricultural region of Galicia (NW Spain), especially where there is intensive pig farming. The aim of this study was to evaluate whether pig farming does affect accumulation of copper and zinc in cattle in Galicia. Hepatic copper and zinc concentrations in calves were elevated in areas with naturally high levels of these elements in the soil. The densities of young pigs (piglets and growing-finishing pigs), but not reproductive sows, also influenced copper accumulation in calves. Liver copper levels in calves were significantly and positively related to the density of young pigs in the region. In areas with the highest pig densities, more than 20% of the cattle analysed had hepatic copper concentrations that exceeded the potentially toxic concentration of 150 mg/kg fresh weight. There was no evidence that zinc accumulation in calves was affected by pig density.  相似文献   
107.
就有机锌对奶牛的营养作用效果、影响有机锌作用效果的因素进行综述。认为添加有机锌可提高奶牛的产奶性能、免疫机能、繁殖性能,改善体健康。同时影响有机锌作用效果的因素有:有机锌的产品质量、添加量和添加时期、饲料营养水平、参照物类型和评价指标等。  相似文献   
108.
试验选用234尾军曹鱼随机分为6个处理,每处理设3个重复,每重复13尾鱼,采用单因素浓度梯度法研究军曹鱼幼鱼商品饲料中锌的最适添加量。在基础日粮(锌含量为75.47mg/kg)中分别添加锌0、30、70、110、150和190mg/kg,制成6种试验日粮,分别投喂军曹鱼幼鱼6周。试验结果表明,基础日粮组鱼成活率、饲料系数、特定生长率、血清碱性磷酸酶(AKP)活性、肌肉和血清锌含量与添加锌组无显著差异(P>0.05)。添加锌组骨骼和肝脏锌含量与基础日粮组差异显著(P<0.05),表现为随锌添加的增加而上升的趋势。以成活率和特定生长率为评价指标,军曹鱼商品日粮中的锌含量可以满足其正常生长需求,不需要额外添加锌。  相似文献   
109.
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   
110.
试验选用360只健康1日龄艾维茵肉仔鸡(公、母混养),采用2×2×3三因子析因化设计,将360只试验雏鸡随机分成12组,每组设3个重复,每个重复10只鸡。锌的添加浓度为50、100mg/kg,铁的添加浓度为30、60mg/kg,维生素A的添加浓度为1500、3000、6000IU/kg。测定了肉仔鸡血清、肝脏谷胱甘肽过氧化物酶(GSH-Px)活性,过氧化氢酶(CAT)活性、铜锌超氧化物歧化(酶CuZn-SOD)活性,丙二醛(MDA)含量,以此来研究不同水平的锌、铁、维生素A同时添加,三者在肉仔鸡血清、肝脏抗氧化功能方面的互作效应。结果表明:锌、铁与维生素A三者互作对提高肉仔鸡血清CuZn-SOD活性影响极显(著P<0.01),对提高肉仔鸡肝脏GSH-Px活性和降低MDA含量影响极显(著P<0.01)。这说明锌、铁、维生素A三者之间在肉仔鸡抗氧化方面存在协同效应。  相似文献   
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