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941.
A 9‐month‐old intact crossbred female cat was presented with jaundice, intermittent anorexia and lethargy, increased hepatic enzyme activities, and hyperammonemia. Abdominal ultrasound and computed tomographic examinations determined that the liver had a rounded and irregular margin, and histopathological examination identified excessive accumulation of copper hepatocytes in the liver. Concentrations of both blood and urine copper were higher than in healthy cats. The patient responded well to treatment with penicillamine. Clinicopathological abnormalities and clinical signs improved within 2 months, and the patient was alive for >9 months after starting treatment. Genetic examination determined that the patient and its littermate had a single‐nucleotide variation (SNV, p. T1297R) that impaired the function of the ATP7B gene product; the gene that is mutated in patients with Wilson's disease (WD). Hepatic copper accumulation was believed to be associated with the SNV of the ATP7B gene, and the patient had a genetic disorder of copper metabolism equivalent to WD in humans.  相似文献   
942.
The varied bioavailability and different effects of organic forms of copper on the immune system of poultry have prompted the search for new feed additives based on copper compounds containing modified chelate complexes. The aim of the study was to determine the effect of inorganic and organic forms of copper on selected parameters of the cellular and humoral immune response in broiler chickens by determining the percentages of CD3+CD4+, CD3+CD8+ and CD25+ lymphocytes, cells with MHC Class II expression, and BU‐1+ cells, as well as the concentrations of SOD, IL‐2, IL‐10 and TNF‐α in the peripheral blood. The experiments were conducted using 500 one‐day‐old Ross 308 roosters divided into five groups. Cu was added in inorganic form (CuSO4), in inorganic form with the addition of phytase (CuSO4 + F), in organic form in combination with glycine (Cu‐Gly) and in organic form in combination with glycine and a phytase supplement (Cu‐Gly+F). The results of the study indicate an increase in the percentage of CD3+CD4+ and CD3+CD8+ T lymphocytes, CD25+ T cells, and cells expressing MHC class II molecules, and in the concentration of ceruloplasmin, activity of superoxide dismutase and the concentration of IL‐2 in the groups that received copper, particularly copper‐glycine chelates. Based on the study, we can conclude that supplementation of poultry feed with copper chelates activates mainly the Th1 cellular immune response and the response of peripheral blood T lymphocytes. Furthermore, it promotes secretion of cytokines, which are involved in potentiation and regulation of the immune response in birds.  相似文献   
943.
In this study, influences of a reduced macromineral intake on the trace element metabolism in horses at maintenance were investigated. Background of this study is the revised recommendation on the macromineral supply for horses (GfE 2014 ). Balance studies on three adult pony geldings with body weights of 405 / 348 / 384 kg were performed to obtain data on apparent digestibility (aD), retention and serum concentrations of different trace elements (Cu, Zn, Se) at different dietary macromineral levels. A mineral supplement or a complementary feed—with a reduced macromineral content—was added to a hay‐based diet (daily 5.5 kg hay per animal, split in three servings a day), beside distilled water was offered. The diets were offered one after the other in a way that all ponies had the same sequence of treatments. The native macromineral contents of the daily offered amount of hay already surpassed the new recommendations whereas dietary trace elements needed to be supplemented. There were no statistically significant differences (p ≤ .05) concerning the aD of copper, zinc and selenium comparing the diets with and without macromineral supplementation. Serum levels of these three trace elements were not affected by the different macromineral content of the diet. Results of this study, based on a 22‐day feeding period for each treatment, indicate that a macromineral supplementation of a hay‐based diet for adult horses at maintenance was not necessary. However, no negative effects of added macrominerals on the trace element metabolism occurred in this study.  相似文献   
944.
本试验旨在研究饲粮铜水平对冬毛期雌性蓝狐生长性能、营养物质消化率、血清生化指标及毛皮品质的影响。试验选取115日龄左右的健康雌性蓝狐50只,随机分成5组,每组10个重复,每个重复1只。以五水硫酸铜(Cu SO_4·5H_2O)为铜源,在基础饲粮中分别添加0、12.22、32.22、72.22、152.22 mg/kg的铜配成5种试验饲粮,5种试验饲粮铜水平分别为7.78(Ⅰ组,作为对照组)、20(Ⅱ组)、40(Ⅲ组)、80(Ⅳ组)、160 mg/kg(Ⅴ组)。预试期为7 d,正试期为60 d。结果表明:1)Ⅲ、Ⅳ和Ⅴ组蓝狐的平均日增重显著高于对照组(P0.05),料重比显著低于对照组(P0.05);各组蓝狐的终末体重及平均日采食量差异不显著(P0.05)。2)各组蓝狐的干物质消化率、蛋白质消化率及氮沉积差异不显著(P0.05);Ⅲ、Ⅳ组蓝狐的脂肪消化率显著高于对照组(P0.05),其他各组间差异不显著(P0.05);铜排出量随着饲粮铜水平的升高极显著的增加(P0.01)。3)Ⅴ组蓝狐血清总蛋白和白蛋白含量显著高于对照组和Ⅱ组(P0.05);Ⅴ组蓝狐血清尿素氮含量显著高于Ⅱ组(P0.05);各组蓝狐血清铜蓝蛋白活性差异不显著(P0.05),Ⅳ组蓝狐血清铜锌超氧化物歧化酶活性显著高于对照组及Ⅱ和Ⅲ组(P0.05)。4)Ⅴ组蓝狐肝脏铜含量显著高于对照组(P0.05),血清铜、锌、铁含量各组间差异不显著(P0.05)。5)饲粮铜水平并未显著影响蓝狐的体长和干皮长(P0.05);Ⅲ和Ⅴ组蓝狐针毛长和绒毛长显著大于Ⅱ和Ⅳ组(P0.05);Ⅴ组蓝狐皮张颜色显著深于对照组(P0.05)。由此可见,在饲粮中添加32.22 mg/kg铜即铜水平为40.00 mg/kg时,冬毛期雌性蓝狐可获得较好的生长性能、营养物质消化率及毛皮品质,同时铜的排放量较低。  相似文献   
945.
Six female cattle were given molybdenum (30 ppm) and sulphate (225 ppm) to induce experimental secondary copper deficiency. The total and differential leukocyte numbers and lymphocyte subpopulations were counted and the neutrophil activity was assessed by means of nitroblue tetrazolium reduction and phagocytosis of sheep erythrocytes. The serum caeruloplasmin activity and concentration were also determined. Copper deficiency was confirmed from decreased serum copper levels, the animals with values less than 5.9 µmol/L being considered deficient. Total leukocyte numbers were not affected by the copper deficiency. However, differential counts showed a marked increase in monocyte subpopulations, a significant decrease in B lymphocytes and reduced neutrophil activity. The serum caeruloplasmin activity was decreased about 50%, but the total serum protein concentration was less altered. We concluded that the effect of these changes on the animals' immune competence may contribute to a greater incidence of infectious diseases in copper-deficient cattle.  相似文献   
946.
为了研究饲粮中添加蛋氨酸铜与硫酸铜对生长猪生长性能、养分消化率、血清铜锌含量及粪铜锌排泄量的影响。选择体重为17.17±2.34kg(P〉0.05)的二元杂交(长×大)生长阉公猪30头进行试验,试猪按完全随机区组设计,依体重和窝别随机分为5个处理,每个处理3个重复,每个重复2头猪,分别饲喂10、150、250mg/kg蛋氨酸铜和150、250mg/kg硫酸铜,试验期30d。结果表明:饲喂蛋氨酸铜组ADG、F/G及表观养分消化率具有明显的优势;血清铜含量随饲粮铜水平的提高而发生显著变化,而高铜组组间血清锌差异不显著;蛋氨酸组粪铜排泄量比硫酸铜组粪铜排泄量显著降低。说明:添加中等水平的有机蛋氨酸铜吸收利用率比高剂量硫酸铜高,且可减少粪铜、锌的排泄。  相似文献   
947.
云南湿热地区距瓣豆的铜、锌和锰营养   总被引:2,自引:1,他引:1  
在云南省亚热带湿热地区为了探讨微量元素铜、锌和锰施用对引进优良豆科牧草距瓣豆生长的影响,开展铜、锌和锰的不同施量对距瓣豆干物质产量、种子产量影响的单因子完全随机区组试验.结果表明,施用铜1.2~2.4 kg/hm2和锰3. kg,/hm2的处理比对照距瓣豆干物质产量分别提高58.4%~88.4%和48.1%(P<0.05),种子产量分别提高295.5%~272.7%和80.4%(P<0.01);施铜还可提高距瓣豆氮、钙、硫、铜、锌和锰含量,显著增加单位面积距瓣豆对氮的需求量(P<0.01),其次是磷、钾、钙、硫、铜、镁、锌和锰的营养需求量(P<0.05);施适量锰可增加距瓣豆的钙、锌和锰含量,显著增加单位面积距瓣豆的钙和锌产量(P<0.01),其次是氮、磷、钾、镁、铜和锰的产量(P<0.05).施用锌虽然对距瓣豆干物质产量和种子产量提高没有显著效果,但是可以提高距瓣豆的钙、锌和锰含量,显著提高单位面积距瓣豆的锌产量(P<0.01),其次是氮、钾和锰的产量(P>0.05),显著的降低距瓣豆对钙(P<0.01)和磷(P<0.05)的吸收量.综合分析,在施磷肥和其他元素肥的基础上,加施铜1.2 kg/hm2或锰3.9 kg/hm2,可获得高产、收益好的距瓣豆优质饲草,同时满足饲养牲畜生产的营养需要.  相似文献   
948.
The aim of this study was to compare, in goats and wethers, the nutritive utilization of diets including olive leaves (OL) and the possible detrimental effect of that by-product. Three different diets were studied: OL, OL plus polyethylene glycol (PEG) (OLP) and OL supplemented with barley [164 g/kg dry matter (DM)] and faba beans (59 g/kg DM) (OLSUP). Apparent digestibility of nutrients and energy and nitrogen balances were determined along with creatinine concentrations and alkaline phosphatase (ALP) activity in the serum. The apparent digestibility of OL was low and similar in goats and wethers (54.4% and 53.5%, 22.2% and 21.6% and, 47.7% and 46.6% for DM, crude protein and neutral detergent fibre in goats and wethers, respectively). The addition of PEG did not improve (p > 0.05) digestibility of OL, although a slightly beneficial effect on the digestion of structural carbohydrates was observed (up to 8.4% and 7.10% in goats and wethers, respectively). The supplementation of OL with barley and faba beans increased (p < 0.001) the apparent digestibility of nutrients and the energy value. The consumption of the OL led to high ALP activity in the serum. Despite the higher sensitivity of wethers to Cu levels, our results show a similar digestive use of OL by wethers and goats and suggest the need of further comparative investigations focusing on the effect of the presence of high Cu levels in the by-product on the animal health.  相似文献   
949.
日粮锰对肉仔鸡组织器官锰、铜、锌沉积的影响   总被引:1,自引:0,他引:1  
选用 1日龄艾维茵肉仔鸡 ,采用单因子多水平随机化试验设计 ,随机分成 6组 ,每组 3个重复 ,每个重复 8只鸡。在玉米 豆粕型基础日粮中分别添加锰 (MnSO4 ·H2 O) 0 ,40 ,80 ,1 2 0 ,1 60 ,2 0 0mg/kg ,研究日粮锰对肉仔鸡组织器官锰、铜、锌沉积的影响。结果表明 :在肉仔鸡日粮中添加 40 2 0 0mg/kg的锰 ,对胫骨锰、肝脏锰和肾脏锰的沉积有显著的影响 (P <0 0 5) ;日粮锰的添加对肝铜和肾铜沉积无明显影响 (P >0 0 5) ,但日粮锰添加量超过 1 2 0mg/kg时 ,能够减少胫骨铜的沉积 (P <0 0 5) ;对胫骨、肝和肾中锌的沉积无明显影响(P >0 0 5)。  相似文献   
950.
Copper-containing bactericides have been used to control bacterial canker of kiwifruit, caused by Pseudomonas syringae pv. actinidiae. However, the efficacy of copper has been reduced by the occurrence of copper-resistant strains. Analysis of the DNA sequence of a cluster region containing the copper-resistance genes from P. syringae pv. actinidiae suggested the presence of three possible different systems for copper resistance: copper-trapping, copper-efflux and copper-transport systems. Transposon insertional inactivation analysis indicated that the copper-trapping system was essential for copper resistance.  相似文献   
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