铜、锌在毛皮动物上的研究进展

毛皮动物是以产毛皮为主的动物,主要包括水貂、狐狸、貉等,近年来我国毛皮动物的养殖日益增大,特别是人工饲养的毛皮动物数量大大增加。1934年,Todd等通过大鼠试验首次证实锌是动物营养所必需的微量元素之一。1928年,Hart发现铜作为生物必需的矿物质元素,并证实铜是鼠血红蛋白合成必不可少的元素,也是动物生长和预防临床和病理紊乱所必需的元素。铜、锌是毛皮动物生长发育和皮毛成熟的重要元素,对于其生产性能、毛皮质量和繁殖性能都有重要影响。文章主要阐述近些年来国内外毛皮动物在锌、铜等微量元素方面的研究状况及锌、铜对毛皮动物的影响。     

毛皮动物对铜、锌的营养需求

正近年来,我国毛皮动物(水貂、狐狸和貉等)养殖日益兴盛,特别是人工饲养的毛皮动物数量大大增加,同时,这也带动了皮革业的急速发展。越来越优质的生活条件使得人们对毛皮的质量要求也日益增高,其中,铜和锌对于毛皮动物生长发育和皮毛成熟起着关键地作用,也对其毛皮质量、生产性能和繁殖性能都有着至关重要的影响。在国外,很早就已经开始研究毛皮动物的营养,主要是从蛋白质、维生素、矿物质等方面展开,而由于国内养殖业兴起的较晚,所以在毛皮动物的饲     

毛皮动物蛋氨酸营养的研究进展

蛋氨酸是毛皮动物第一限制性氨基酸,是影响毛皮动物养殖经济效益的一个重要因素,科研工作者对此作了大量的研究工作。作者回顾了国内外蛋氨酸在毛皮动物营养上的研究进展,结合蛋氨酸的生物学功能及蛋氨酸对动物营养作用机制和毛皮相关基因的影响等方面进行了综述,为蛋氨酸在毛皮动物上的进一步研究提供依据,同时提出了目前蛋氨酸在毛皮动物营养研究上存在的问题及进一步的研究方向。     

微量元素锌和铜与免疫

锌、硒、铜、铬等作为动物必需的微量元素 ,在动物营养中已得到广泛的研究和应用。近些年有关微量元素对动物机体免疫作用的研究愈来愈受到关注。所谓免疫反应是指动物机体识别和清除抗原性物质 ,以维护机体内外环境相对稳定所发生的一系列反应。试验研究表明 ,合理的营养水平可保证动物各组织、器官功能处于最佳状态 ,强化动物的防御和免疫系统 ,增强动物对疾病的抵抗能力[1] 。本文主要论述了微量元素锌、铜在家畜免疫反应中的应用效果。1　锌与免疫锌是动物营养中必需的营养元素 ,不仅为维持动物机体生长发育所必需 ,而且也是动物免疫系…     

微量元素在动物饲料中应用研究进展

微量元素在动物营养中的作用越来越重要。本文就微量元素铜、铁、锌、锰及重金属铅的生理功能、吸收与耐受量以及在动物营养中的研究进展等方面进行了综述。     

藏鸡胸肌中锌铜含量的测定与分析

随着生物科学的不断发展,微量元素在动物体内的营养作用日益受到人们的重视。本试验旨在测定藏鸡胸肌中锌和铜的含量,并与其它动物体内相同矿物元素的含量做比较,从而探讨铜、锌含量对藏鸡品质的影响。     

毛皮动物用动物源性蛋白原料营养指标及安全指标分析

研究对采集到的毛皮动物用动物源性蛋白原料的营养指标和安全指标进行测定分析,以便为这些原料在毛皮动物养殖中充分利用提供数据支持。     

毛皮动物营养研究进展

毛皮动物的消化道短,消化能力弱,不适合消化高纤维食物,而以消化高蛋白、高脂肪的动物性饲料为主。研究表明,蛋白质和脂肪是毛皮动物必需的营养来源,碳水化合物、矿物质和维生素则既对毛皮动物的毛皮质量产生重要影响,同时还与一些代谢疾病的发生、发展有密切的关联。此外,人们对毛皮动物的能量需求及其饲料能值的研究也取得了一定的进展。     

当前国际毛皮动物营养研究进展

毛皮动物的消化道短,消化能力弱,不适合消化高纤维食物,而以消化高蛋白高脂肪的动物性饲料为主。研究表明,蛋白质和脂肪是毛皮动物必需的营养来源,碳水化合物、矿物质和维生素则既对毛皮动物的毛皮质量产生重要影响,同时还与一些代谢疾病的发生发展有密切的关联。此外,关于毛皮动物的能量需求及其饲料能值的研究也取得了一定的进展。     

毛皮动物钙、磷代谢与维生素D的研究进展

钙、磷是毛皮动物代谢需要的重要元素,维生素D在调节毛皮动物钙、磷吸收、调节其骨骼钙、磷的沉积和溶解中发挥着重要作用。文章总结了毛皮动物钙、磷及维生素D基本功能,概述其过量和缺乏引起的症状,分析了目前毛皮动物饲料生产中钙、磷和维生素D添加量中存在的问题,并提出有效的解决方法,结合国内外学者的研究成果总结出了毛皮动物饲料中钙、磷及维生素D适宜的添加水平,并提出了毛皮动物钙、磷及维生素D营养的进一步研究方向。     

Effect of staphylococcal contamination of the bovine udder on milk yield

Zinc sulphate was added to the drinking water of Angus cows and calves grazing an area considered marginal for copper nutrition of cattle. Mean daily intakes of approximately 12–15 mg Zn/kg live-weight further depressed already low plasma copper concentrations to levels considered to indicate copper deficiency. The plasma copper concentrations in untreated animals increased during the trial indicating adequate copper intakes during this period, but the high zinc intakes of treated animals prevented this seasonal rise. Injection of copper glycinate (0.24 g/animal) alleviated the depression of plasma copper associated with the high zinc intakes. The zinc supplements had little effect on plasma zinc concentrations.     

Zinc toxicity, copper deficiency and anaemia in swill-fed pigs

Zinc toxicity, copper deficiency and an associated anaemia among weaned swill-fed pigs is described. The source of zinc was flaking galvanising from the inside of bins used to store swill before processing. The disease condition readily responded to supplementation of the diet with copper sulphate. The interactions between dietary zinc, copper and calcium are discussed with reference to the swill-feeding industry. It is concluded that supplementary copper should be routinely included in the ration of swill-fed pigs and that the use of galvanised bins for storing swill should be avoided.     

动物铁、铜、锌、硒代谢及缺乏症研究新进展

微量元素铁、铜、锌、硒在动物生命活动中其中非常重要的作用,缺乏可导致动物患发一系列的病症。动物缺铁可导致其生长发育受阻及免疫力降低;铜缺乏时可有被毛稀疏、粗糙、缺乏光泽、弹性降低、颜色变浅等症状;缺锌时可表现鼻镜干燥,爪垫增厚或龟裂,被毛发育不良、易断;硒缺乏可表现被毛粗糙,骨骼肌变性、退色。     

Level of heavy metals in the liver of sheep in experimental poisoning with copper oxide from industrial emissions

The life span and cumulation of heavy metals in the liver of 12 ewes of the Improved Wallachian breed were investigated in relation to feeding pollutants from a copper works. The total intake of copper, iron, zinc, arsenic, cadmium and lead was 466.8; 1253.93; 111.67; 34.75; 0.091; 2.13 mg per experimental animal/day, respectively. The average life span of ewes in the experimental group was 77 days. The difference between the first and the last animal which died from copper intoxication was 18 days. The concentration of copper in the liver of sheep who died from intoxication by this metal (2138.28 +/- 1090.96 mg. kg-1 in dry matter) was significantly higher (p less than 0.01) if compared with the control ewes (212.9 +/- 58.33 mg. .kg-1 in dry matter). In the course of observations no direct dependence between the concentration of copper in the liver and the life span of experimental animals was confirmed. The content of iron and zinc in the liver of experimental animals was within the reference range; the difference in zinc was statistically significant when compared with the control group (p less than 0.01). The intake of pollutants from the copper works increased significantly the concentration of arsenic and lead in the liver of experimental animals (p less than 0.01) if compared with the control group. The amount of cadmium in the liver of experimental ewes was 0.304 +/- 0.22 mg. .kg-1 and in the control ewes 0.285 +/- 0.10 mg.kg-1 in dry matter; no significant difference was determined at the same time.     

Trace elements in grass, cattle liver and sheep liver from districts surrounding Karatina, Kenya. II. Copper, molybdenum, zinc and sulphur

Thirty-one samples of pasture grass from districts surrounding Karatina, Kenya were analysed for contents of copper, molybdenum, zinc and sulphur. The following mean values and standard deviations were found: Copper: 8.2 +/- 5.0 mg/kg DM; molybdenum: 1.4 +/- 2.6 mg/kg DM; zinc: 33 +/- 10 mg/kg DM and sulphur: 0.17 +/- 0.06% DM. Mean value of the ratio between copper and molybdenum was 13 +/- 11. Samples of cattle liver (n = 96) and sheep liver (n = 93) were analysed for copper and zinc with the following results: Cattle liver: 21 +/- 16 mg Cu/kg WW and 37 +/- 11 mg Zn/kg WW. Sheep liver: 59 +/- 37 mg Cu/kg WW and 30 +/- 6.4 mg Zn/kg WW. It is concluded that subclinical copper deficiency may occur in cattle in the districts included in the investigation. The copper status of sheep seems to be adequate. The levels of zinc may indicate a marginal intake of this element in sheep.     

Influence of different copper and zinc supply on their concentrations in blood serum, liver and hair of dairy cows

In a feeding trial at the Institute of Animal Nutrition of the Federal Research Institute of Animal Health (FLI) over 12 weeks with 20 cows of the German Holstein Breed the influence of different copper and zinc contents in the ration on their concentration in blood serum, liver and hair was tested. All animals received a diet based on maize- and grass silage ad libitum. The animals were divided in two groups with 10 cows each; group A received a concentrate according to their milk yield with a copper and zinc content as recommended (GfE 2001), whereas group B was offered a concentrate with roughly the double amount of copper and zinc. At the beginning and at the end of the trial a sample of blood, pigmented hair and a liver bioptate was taken from all animals to evaluate the incorporation of copper and zinc in these tissues. In serum and pigmented hair the copper concentrations did not differ between the two groups [13.4 for Group A and 12.5 micromol/L for Group B in serum respectively 6.8 (Group A) and 7.4 mg/kg DM (Group B) in pigmented hair]. Only the copper concentration in the liver was influenced by the different feeding. The higher copper content for group B resulted in a significantly higher copper concentration in the liver (506 mg/kg DM compared to 383 mg/kg DM). The liver is the best indicator organ for a sufficient copper supply. An increase in the zinc content in the ration resulted neither in higher zinc concentrations in serum (15.1 in Group B in comparison to 13.4 micromol/L for Group A) nor in higher zinc concentrations in liver (140 for Group B and 112 mg/kg DM for Group A) and pigmented hair (130 in Group A and 123 mg/kg DM in Group B). There is a significant correlation between copper intake and copper concentration in the liver (r = 0.46), whereas the correlation between zinc intake and zinc concentration in the liver is only tendencially (r = 0.23). The three tested samples serum, liver and cow hair are not qualified to reflect exactly a sufficient zinc supply.     

Assessment of copper and zinc status of farm horses and training thoroughbreds in south-east Queensland

The copper and zinc concentrations in the blood of stabled thoroughbred horses and in Australian Stock Horses mares at pasture, either late pregnant or lactating were determined by an atomic absorption spectroscopic method. The plasma concentration of the trace elements in these apparently normal horses were generally below the "normal" range. The plasma copper, caeruloplasmin copper, whole blood copper and plasma zinc concentrations in the stabled thoroughbreds were 0.76 +/- 0.19 micrograms/ml (n = 82), 0.56 +/- 0.14 micrograms/ml (n = 83), 0.75 +/- 0.18 micrograms/ml (n = 82) and 0.47 +/- 0.09 micrograms/ml (n = 83) respectively. The plasma copper and zinc concentrations of all the brood mares at pasture (pregnant and lactating) were 0.56 +/- 0.20 micrograms/ml and 0.47 +/- 0.11 micrograms/ml (n = 30). The plasma copper concentration of the pregnant group of mares (0.64 +/- 0.18 micrograms/ml; (n = 14) was greater than that of the lactating mares (0.49 +/- 0.21; (n = 16). Variation in the plasma copper concentration was also identified between stabled and farm horses, between horses of different stables and between horses of different ages. The proportion of plasma copper bound to caeruloplasmin was 73 +/- 11.8%. These low concentrations of copper and zinc in the plasma of apparently normal horses are of clinical significance since recent evidence has indicated that copper deficiency appears to promote the development of skeletal abnormalities in foals. An alternative to the use of a single plasma sample to identify the copper or zinc deficient horse was discussed.     

Induction of zinc deficiency in sheep and its correction with a soluble glass bolus containing zinc

Balance studies were carried out on four Suffolk-cross lambs which were fed a diet containing only 1.2 mg zinc/kg dry matter; zinc deficiency was induced within three weeks. After a period during which the deficiency was relieved by a pica, the zinc deficient state was re-established. Each sheep was then treated with a soluble glass bolus containing zinc, cobalt and selenium. The plasma zinc concentration of the sheep rapidly increased and was maintained for between six and 10 weeks. The bolus was able to supply the daily requirement of the sheep for zinc, with no detrimental effect on their copper status.     

Skin disease in dogs associated with zinc deficiency: a report of five cases

The literature on zinc deficiency is discussed. Five cases of skin disease in dogs associated with zinc deficiency are described. All the animals were Labrador Retrievers. Lesions in all cases were similar and consisted of a dry hair coat, mild generalized seborrhoea sicca and bilaterally symmetrical, focal, yellow crusts and scale over the distal parts of the limbs and the chin. These were accompanied by ceruminous otitis externa and superficial lymphomegaly. The serum and hair zinc concentrations were markedly subnormal in all cases. Treatment with oral zinc sulphate produced a rapid resolution of physical signs and restoration of serum zinc concentrations to the reference range. All dogs were fed on unsupplemented cereal-based diets. The clinical condition appeared to arise from dietary imbalances rather than an absolute deficiency of zinc, although there may have been accompanying inherent defects of zinc absorption in some cases.     

Evaluation of a commercially available molybdate formulation and zinc oxide boluses in preventing hepatic copper accumulation and thus enzootic icterus in sheep

The efficacy of a molybdate formulation and a zinc oxide bolus as prophylactic agents for enzootic icterus was evaluated in sheep. Before copper loading, liver biopsies were performed on 12 male, 6-month-old, Mutton Merino sheep to determine hepatic copper (Cu) and zinc (Zn) concentrations. The animals were restrictively randomised according to liver copper concentrations to 3 treatment groups (n = 4) to achieve similar mean liver copper concentrations per group. All sheep received 4 ml/kg of a 0.5 % aqueous solution of CuSO4 5H2O intraruminally 7 days per week for 10 weeks. On Day 0 the sheep in the Mo-group were injected subcutaneously with 42 mg molybdenum (Mo) contained in a commercial molybdate formulation. The animals in the Zn-group each received a zinc oxide bolus, containing 43 g zinc oxide, via a rumen cannula. Treatment was repeated on Day 42. Four animals served as untreated controls. Urinary copper excretion, plasma copper concentration, haematocrit and glutamate dehydrogenase (GLDH) activity were determined throughout the trial. The animals were sacrificed after 10 weeks and liver samples were submitted for histopathological examination. Liver and kidney copper and zinc concentrations were determined. Neither the molybdate treatment nor the zinc oxide boluses prevented hepatic copper accumulation. The urinary copper excretion, plasma copper concentration, haematocrit and GLDH activity were not significantly different (P > 0.05) from the controls.