奶牛乳房炎的综合防治

乳房炎是乳腺受到物理、化学、微生物的刺激所发生的一种炎性变化,主要是由多种非特定的病原微生物引起的,是严重危害奶牛养殖业发展的主要疾病之一。据调查表明:美国30％～70％的母牛至少有一个乳区被感染,在我国奶牛乳房炎发病率约为46.6％～85.1％,导致产奶量下降,增加养殖奶牛的成本。因此,有效合理地防治奶牛乳房炎迫在眉睫。 1、发病时间     

奶牛乳房炎的综合防治

<正> 乳房炎是乳腺受到物理、化学、微生物学刺激所发生的一种炎性变化,主要是由多种非特定的病原微生物引起的,是世界上严重危害奶牛养殖业发展的主要疾病之一。据调查表明:美国30%～70%的母牛至少有一个被感染的乳区,我国奶牛乳房炎约为46.6～85.7%,导致产奶量下降,增加养殖奶牛的成本,因此,有效合理的     

奶牛乳房炎的综合防治

乳房炎是奶牛的常见多发病，经常给奶牛养殖造成重大损失，应积极采取有效措施，搞好防治。     

奶牛隐性乳房炎的综合防治措施

我国奶牛乳房炎的发病率很高,隐形乳房炎的发病率更高、为害性更大.阐述了奶牛隐性乳房炎的发病原因,并从饲养管理、环境卫生、挤奶程序和放牧方式等方面介绍了综合防治措施.     

奶牛乳房炎综合防治措施

介绍了奶牛乳房炎的综合防治措施,包括做好疾病监测、保持环境卫生、规范挤奶程序、干奶期乳房炎的预防、及时治疗和淘汰病牛、加强饲养管理等内容,以供养殖户参考。     

改善挤奶技术降低乳房炎的研究

本文研究结果表明：乳房炎（ＰＬ－乳房炎简易诊断法）检查结果为全群挤奶牛各乳区乳房炎检查阴性率从４７％提高到８１％，初产泌乳牛阴性率从６９％提高到９２％，第二胎泌乳牛阴性率从２５％提高到８２％，第３胎以上泌乳牛阴性率从２７％提高到６８％。由此可见采用正确挤奶顺序对降低乳房炎具有显著效果。     

奶牛子宫内膜炎早期诊断的实验研究

通过对８０头产后奶牛子宫分泌物抹片细胞学显微镜观察，发现中性粒细胞噬菌现象与子宫内膜炎有相关性，结合分泌物的眼观变化，可对子宫内膜炎做出早期诊断。平实验可为奶牛子宫内膜炎早期诊断提供细胞学依据。     

呼和浩特市伟嘉公司奶牛场奶牛隐性乳房炎的调查及防治初探

笔者对呼市伟嘉公司奶牛场奶牛隐性乳房炎的发病情况和防治工作进行初步调查,并参与了该牛场对乳房炎的防治工作.该牛场有泌乳奶牛200头,用加州乳房炎试验(CMT)进行检查,阳性者为97头,隐性乳房炎阳性率为48.5％,通过在饲料中拌入“乳炎散”治疗隐性乳房炎,每头1d 300g,连用9d,情况大为好转,治愈率为80％.     

黑龙江垦区户养奶牛适度规模的初探

通过对黑龙江垦区个体奶牛户的经验规模、最低规模和优化规模研究，确定了适度经营规模：个体养奶牛以10头为宜．在此规模下可获得较好的经济效益．     

大肠杆菌内毒素诱导奶山羊急性乳房炎试验

试验研究了大肠杆菌内毒素乳房灌注在奶山羊引起的临床反应。结果表明，大肠杆菌内毒素注入杂种奶山羊乳池内能诱导出典型的急性乳房炎局部症状和全身症状：乳房肿胀，发热疼痛，体温升高，产奶量下降等。超声波图象说明，水肿是急性乳房肿胀的主要原因。随着局部炎症消失，乳腺组织能迅速达到临床上的完全康复。     

奶牛隐性乳房炎的发生规律及其致病菌的分离鉴别与药物敏感性试验

本文对内蒙古大黑河奶牛场的泌乳牛群进行隐性乳房炎的检测，及其致病菌的分离鉴别与药物敏感试验，其结果：①共检测泌乳牛283头次1078个乳区，隐性乳房炎的头阳性率为61．84％，乳区阳性率为32．28％，并且其发生与管理、挤奶卫生及其程序、泌乳期、年龄、胎次有很大关系；②致病菌的总检出率为92．31％，其主要病原菌为金黄色葡萄球菌，无乳链球菌和大肠杆菌，分别占总检出率的41．66％、20．83％和16．67％。③对所检出的病菌，一些新药物敏感性较好，而一些常用药物效果较次。     

奶牛胚胎移植实用技术的研究

我们于１９９６年至１９９７年进行了奶牛胚胎移植实用技术的研究。三年共移植奶牛胚胎１３７枚,受胎率为３５．７７％,移植Ａ级胚胎的受胎率为７０％,移植Ｂ级胚胎受胎率为４３．０２％,移植Ｃ级胚胎的受胎率为１２．１９％,移植Ａ级胚胎的受胎率比移植Ｂ级胚胎受胎率高２６．９８％;移植Ａ组胚胎的受胎率分别比移植Ｃ级胚胎受胎率有５７．８１％和３０．８３％。     

奶牛白血病肿瘤器官网状纤维和胶原纤维病理形态学变化的研究

Some tissues and organs were determined histologically in 10 dairy cows with lymphatic leukosis。Reticular fibers in the hyperplasia area of tumor cells changed to varying extent。Reticular fibers enlarged in mild tumors and fragmented and dissoluted in severe tumors，and structure of reticular fibers didn’t chang in the organs without tumor。The normal and paranormal chang of collagenous fbers were observed。     

NEW ZEALAND DAIRY FARM SYSTEMS AND KEY ENVIRONMENTAL EFFECTS

• NZ dairy farming systems are based on year-round grazing of perennial pasture (ryegrass/white clover). • Milk production per hectare has increased by about 29% with increased use of externally-sourced feeds over the last two decades. • Externally-sourced feeds with a low protein concentration can potentially reduce N₂O emissions and N leaching per unit of production. • Systems analysis is important for evaluating mitigations to minimize trade-offs between environmental impacts. This paper provides an overview of the range of dairy pasture grazing systems used in New Zealand (NZ), the changes with increased inputs over time and associated key environmental effects including nitrogen (N) leaching and greenhouse gas (GHG) emissions. NZ dairy farming systems are based on year-round grazing and seasonal milk production on perennial ryegrass/clover pasture where cows are rotationally grazed in paddocks. There was an increase in stocking rate on NZ dairy farms from 2.62 cows ha⁻¹ in 2000/2001 to 2.84 cows ha⁻¹ in 2015/2016. During the same period annual milk solids production increased from 315 to 378 kg·yr⁻¹ per cow. This performance has coincided with an increase in N fertilizer use (by ~ 30%) and a twofold increase in externally-sourced feeds. Externally-sourced feeds with a low protein concentration (e.g., maize silage) can increase the efficiency of N utilization and potentially reduce N losses per unit of production. Off-paddock facilities (such as standoff or feed pads) are often used to restrict grazing during very wet winter conditions. A systems analysis of contrasting dairy farms in Waikato (largest NZ dairying region) indicates that the increased input would result in an increase in per-cow milk production but little change in efficiency of milk production from a total land use perspective. This analysis also shows that the increased inputs caused an 11% decrease in N footprint (i.e., N emissions per unit of milk production) and a 2% increase in C footprint (i.e., greenhouse gas (GHG) emissions per unit of milk production).     

奶牛鲜胚的非手术移植

1988年3—10月,超排处理6头供体牛,成功率83.3%;进行了5头次非手术采卵,成功率100%;共获得胚胎43枚,平均每头8.6枚,其中可用胚胎27枚,平均每头5.4枚.采用非手术座植方法,先后将9枚胚胎移植给6头受体牛,结果4头妊娠,妊娠率为66.6%.1989年1月24日,一头受体母牛顺利产犊;另2头妊娠受体母牛于7月14日,17日分娩,还有一头受体母牛(已妊165天)不幸于1988年10月因跌伤而流产.