肉用牛微量元素需要量及中毒量

微量元素是牛生长发育及生产性能发挥所必需的元素。随着肉用牛生产水平的提高,肉牛微量元素营养研究也在不断深入,正确掌握微量元素的需要量,对肉用牛生产性能的发挥将起积极作用。现就肉牛(改良黄牛、黄牛)微量元素需要量及中毒量介绍如下,供添加剂生产及肉牛饲养户参考。     

奶牛微量矿物元素的营养研究进展

本文对奶牛微量元素营养作用及其在奶牛生产中的应用效果研究，微量元素需要量及其相互作用的研究，微量元素的补充及其生物利用率的研究等内容予以综述。     

铜在奶牛上的营养作用研究

铜是动物体内必需的矿物质之一,虽然在动物体内含量很低,但却在动物体内特别在奶牛体内具有广泛的生物学效应,不仅能够影响奶牛的生长、生产性能,更对奶牛自身免疫和抗氧化性能产生很大的影响,且处在不同时期的奶牛及不同品种的奶牛对其需要量均不同。因此,本文综述了微量元素铜在奶牛的生长、生产、免疫、繁殖和抗氧化性能上研究进展,以及奶牛对于铜需要量的研究,旨在为微量元素铜在奶牛营养作用上的研究提供理论依据。     

奶牛对微量元素铜的营养需要研究

铜是奶牛正常生长发育和生产所必需的元素。由于各地的自然条件复杂,土壤类型各异,植物种类不同,导致饲草料中所含的微量元素铜存在很大的差异,各地区均存在不同程度缺乏与过量的问题．而且在饲养管理过程中存在着许多影响铜吸收率的因素。因此,本文就奶牛对微量元素铜的需要量及铜对奶牛的影响因素做一阐述。     

世界各国家禽饲养标准参数浅析

本文综述了中、美、澳、日、法及前苏联六国最新发表的有关禽类饲养标准等方面的研究成果,分家禽能量需要量及能量蛋白比、蛋白质及氨基酸需要量、矿物质需要量、微量元素需要量、维生素需要量五部分,按家禽类型、生长阶段、生产性能等分别进行了分析比较,以资参考。     

奶牛铁铜锌锰4种微量元素营养

针对生产实验，就铁、铜、锌、锰４种微量元素对于奶牛的生理功能、缺乏与过量症状、营养需要量，补给办法及原料选择等方面进行了综合论述。     

奶牛营养需要量与日粮配制指南

鉴于目前我国奶牛饲养逐步从粗放饲养向精细饲养转型过程中对奶牛日粮配方设计的技术需求,文章以NRC(2001)发布的《奶牛营养需要量》为基础,并结合2001年后有关奶牛营养需要量新的研究进展和饲养奶牛积累的经验,主要就泌乳奶牛和干奶牛对干物质采食量、能量需要量、碳水化合物、脂肪、蛋白质和氨基酸、矿物质和维生素需要量等进行了数量化的描述,并总结了设计配方时日粮养分指标理论上的规格,也包含一些对关键养分的评定与计算方法,以及目前还尚未理清的最佳的营养需要量指标等。总之,本文为计算奶牛综合的、动态的营养需要量及设计奶牛日粮配方主要的问题提供了便捷的和定量的参考指南。     

奶牛养殖中被忽视的常量矿物元素--钾、镁和硫

钾、镁和硫是奶牛必需的常量矿物元素,虽然这一点是业内工作者的共识,但在奶牛养殖中通常并不重视它们,其原因主要是认为常规饲料原料中的含量足以满足动物的需要量,因此对其需要量和饲料原料中有效含量的认识要远少于钙磷。随着奶牛现代集约化养殖以及奶牛品种的改进和生产效率的提高,奶牛对各种营养物质的需求都在不断提升,如果奶牛养殖中仍然忽视钾、镁和硫的补充,越将对奶牛的健康和生产性能带来不利的影响,造成一定程度的经济损失。     

高效奶牛饲养技术

高效奶牛饲养技术西北农业大学畜牧系姚军虎，金公亮第二讲奶牛的养分代谢及养分需要量特点奶牛在生存、生长及产奶过程中，需要各种各样的养分，这些养分包括能量、蛋白质和氨基酸、维生素、矿物质及微量元素等。其中一部分养分用于维持奶牛本身的生命，表现在基础代谢、...     

奶牛养殖中被忽视的常量矿物元素——钾、镁和硫

钾、镁和硫是奶牛必需的常量矿物元素,虽然这一点是业内工作者的共识,但在奶牛养殖中通常并不重视它们,其原因主要是认为常规饲料原料中的含量足以满足动物的需要量,因此对其需要量和饲料原料中有效含量的认识要远少于钙磷.随着奶牛现代集约化养殖以及奶牛品种的改进和生产效率的提高,奶牛对各种营养物质的需求都在不断提升,如果奶牛养殖中仍然忽视钾、镁和硫的补充,必将对奶牛的健康和生产性能带来不利的影响,造成一定程度的经济损失.     

荷斯坦奶牛维持净能需要量的测定及影响因素

介绍2种评定奶牛维持净能需要(NEm)的方法及其优缺点;并分析了造成近20年荷斯坦奶牛NEm提高的原因。     

不同受体牛对黑毛和牛冷冻胚胎移植的效果

[目的]选择不同品种牛,利用同期发情和自然发情后作为受体牛,进行日本和牛冻胚移植研究。[方法]选择奶牛20头和南德温杂种肉牛41头作为受体牛,利用CIDR+PG做人工同期发情处理,发情后的受体牛移植和牛冻胚。统计分析受体牛的同期发情率和移植后的妊娠率。[结果]试验结果表明奶牛和南德温杂种肉牛的受体牛同期发情率分别为90.00%和85.36%,差异显著(P<0.05);在同一牛场场使用不同品种受体牛进行冻胚移植试验结果表明,15头奶牛和27头南德温杂种肉牛受体牛妊娠率分别为46.67%和48.14%,差异不显著(P>0.05)。[结论]只要符合胚胎移植受体牛要求,奶牛和南德温杂种肉牛均可作为和牛胚胎移植受体牛。     

叶面喷施微肥对牧草、奶牛微量元素代谢的影响

试验采用含硒、锌、铜、锰等元素的微肥对牧草进行叶面施肥，研究通过这种施肥途径对牧草品质的影响。同时采用此种牧草饲喂奶牛，研究这种牧草对奶牛血液中相应元素含量及奶牛生产水平的影响。结果表明，牧草中硒、锌、铜、锰的含量有显著的提高；奶牛采食这种牧草90d后，血液中硒、锌、铜的含量显著提高，生活水平有所增长。     

饲喂赛乐锌对奶牛血液生化指标和生产性能的影响

[目的]通过饲喂试验,探究日粮中添加赛乐锌对奶牛生化指标和生产性能的影响。[方法]将试验奶牛随机分为4个处理,每个处理2个重复,采用4×4拉丁方设计,进行饲喂试验。[结果]表明,在奶牛日粮中添加350mg/kg的赛乐锌,奶牛血清锌浓度和血清碱性磷酸酶(AKP)活性显著提高(P0.05);各试验组血清尿素氮浓度呈下降趋势,但差异不显著(P0.05)。[结论]在不影响乳脂率和乳蛋白率的前提下,显著提高奶牛的产奶量,牛奶中乳锌的含量显著提高,使牛乳的品质得到很大程度的提升。     

微量元素铜对奶牛营养作用及生产性能的影响

本文综述了国内外关于奶牛铜营养的试验与研究,旨在说明微量元素铜对奶牛的生理学作用、生物学效应,揭示微量元素铜对于奶牛营养的重要性.并总结了铜缺乏的临床表现及铜源的选择与供给,为在奶牛日粮中添加合理剂量的铜做出了指导与建议,目的在于提高奶牛的生产性能,增加养殖的经济效益.     

Mineral and water nutrition

In providing minerals to dairy cattle it is important to distinguish between dietary requirements and feeding recommendations. The requirement is the absolute amount of an element needed to meet the animal's metabolic needs for maintenance, growth, pregnancy, and lactation divided by the coefficient of absorption; this is estimated by the factorial method. Actual estimates of requirements for lactating dairy cattle have been determined for Ca and P. The major difficulties in relying on the requirement estimate are that dry matter intake varies and the true absorption coefficient of the mixture of feeds in the ration generally is unknown. Therefore, feeding recommendations, based on feeding graded concentrations of an element, often offer more applicable information. With the exception of Ca and P, the current feeding recommendations for the other macrominerals, Mg, Na, K, Cl and S, have resulted from feeding trials. With certain environmental and physiologic situations the feeding recommendations may vary. For example, during heat stress the dietary K recommendation for the lactating cow should be higher than in cool weather because of increased sweating and decreased feed intake. Another example may be that the source of supplemental Mg may affect what dietary inclusion rate will yield optimal performance and should be recommended. An important consideration in dairy ration formulation in the future will address the interrelationships of the various macrominerals. There is accumulating evidence that shows that different concentrations of Na, Cl, and K may interrelate and affect lactational performance. Many times the naturally occurring concentrations of one or more of these elements may have to be associated with varying concentrations of the others in order to optimize animal performance and health. Much experimentation likely will examine these interrelationships in the future. Supplementation of trace elements in diets of dairy cattle is common practice. This is because the quantities found in common feedstuffs are relatively low relative to the animal's needs and vary considerably among and within feeds. Supplementation provides a safety margin against potential deficiency. The reader is cautioned to consult other publications regarding potential interactions among the trace elements and their interactions with other nutrients. Potential oversupplementation is a real concern. Maximum safe tolerance concentrations for most trace elements are available. Water is the most important indispensable nutrient. Water requirements are affected by physiologic state and rate of milk yield, body weight, rate of dry matter intake, Na intake, and average minimum environmental temperature. Practically, offering a fresh, abundant supply of easily accessible drinking water at all times is essential.(ABSTRACT TRUNCATED AT 400 WORDS)     

奶牛围产期饲养管理的方法

笔者针对养殖者的不明围产期奶牛生理特征和营养需求,未进行营养调整而造成的损失问题,围绕围产前后期饲养管理提出了应注意的几方面,以期为养殖户提供技术指导。     

中药治疗奶牛乳房炎的研究现状与展望

综述了中药治疗奶牛乳房炎的临床应用、机理和特点,认为中药治疗奶牛乳房炎采用辨证施治方法,毒副作用小且不易产生耐药性;指出了中药治疗奶牛乳房炎存在的问题,主要是基础研究薄弱、生产工艺落后、无固定标准、药品质量难以保证等.由于中药治疗奶牛乳房炎疗效确实,因而潜力巨大.     

不同类型奶牛场牛奶乳脂率及酸度变化特点研究

奶牛生产方式是影响奶牛奶产量和质量的重要因素。本文通过对兰州市晏家坪奶牛养殖小区、甘肃农业大学实验奶牛场、兰州市个体养殖户三种不同类型奶牛场的牛奶乳脂率及酸度指标分析,表明不同生产方式下牛奶质量差别较大,以相对规模化、集约化生产的奶牛养殖小区牛奶质量最好,个体养殖户牛奶质量较差。因此,在奶牛生产中,采用规模化、集约化的生产模式是保证牛奶质量的重要措施之一。     

Evaluation of antimicrobial use in dairy cattle,beef cattle and broilers in Japan using dosage-based indicators

The sales amount of antimicrobials intended for use in dairy cattle, beef cattle and broilers from 2008 to 2019 was evaluated for each antimicrobial class and administration route using dosage-based indicators. Our results revealed that the antimicrobial sales amount sold for use in dairy cattle in 2019 in terms of total weight of active ingredient, the number of defined daily doses (DDDs) (theoretical amount of biomass subjected to antimicrobial treatment in a year) and the number of treatment days (TDs) (theoretical number of days of treatment that an animal is subjected to in a year) calculated using Japanese DDD values (DDDjp values) was 36,751 kg, 8,261,848,000 kg·days and 15.5 days, respectively. Likewise, the antimicrobial sales amount sold for use in beef cattle and broilers in 2019 in terms of these metrics was 33,403 kg, 3,928,248,000 kg·days and 3.61 days, and 69,773 kg, 2,947,848,000 kg·days and 10.66 days, respectively. There was a considerable difference between the number of DDDs calculated using DDDjp values and that calculated using European DDD values (DDDvet values) for antimicrobial products sold for use in dairy and beef cattle. Our results also revealed that the sales amount of some antimicrobials, such as cephalosporins and quinolones represented larger proportions when calculated using dosage-based indicators than when calculated using the weight of active ingredient. Considering that Japanese veterinarians and farmers are more likely to conform to the Japanese dosage recommendations rather than the European ones, these results indicate the need for using dosage-based metrics, in particular metrics based on Japanese dosages rather than European dosages.