奶牛隐性乳房炎研究进展

隐性乳房炎是奶牛高发病之一,对奶牛及奶业发展造成了重要影响。该文对奶牛隐性乳房炎的发病原因、发病规律、诊断方法、预防措施等进行了探讨,并介绍了基因疫苗和细胞因子在乳房炎预防中的作用,以及PCR与蛋白组学方法在奶牛乳房炎诊断方面的应用。     

奶牛隐性乳房炎的治疗与预防

(一)诊断患隐性乳房炎的奶牛,病原菌已侵入奶牛乳房,但无临床症状,乳汁无感官异常,而炎症反应已在乳腺内部进行蔓延,用试剂可以检出来.用0.2%溴麝香酚蓝(溴麝香酚蓝0.2克加10%的酒精50毫升制成)作为指示剂在白纸上滴一滴,颜色呈黄色,然后,滴上被检乳牛的乳汁,如果变绿,说明奶牛产奶量已经下降,初步诊断为隐性乳房炎,如颜色不变,则表示没有乳房炎.     

奶牛隐性乳房炎研究进展

乳房炎是奶牛群中危害最大的一类疾病。隐性乳房炎占奶牛乳房炎发病率的90％。本文主要介绍了隐性乳房炎的发病率、危害程度、诊断方法及预防措施。     

奶牛隐性乳房炎的检测及预防

奶牛隐性乳房炎是危害奶牛场生产作业的重要疾病之一,防治不当将造成巨额经济损失。对四川雅安地区某牛场的86头泌乳期奶牛进行隐性乳房炎发病情况的调查统计。采用兰州乳房炎检测法(LMT)对隐性乳房炎进行检测,结果显示,该牛场隐性乳房炎的发病率达44.77%。采取科学的防治措施能够有效预防和控制奶牛乳房炎的发生。     

奶牛乳房炎试纸与隐性乳房炎的防治

１什么是奶牛隐性乳房炎奶牛隐性乳房炎是一种发病率高，没有临床症状，也就是奶水是白色乳状，乳房组织有肿胀和痛疼，但是乳汁的生物化学、乳汁成份则发生变化，肉眼看不到乳汁和乳房变化，所以叫做隐性乳房炎。隐性乳房炎有什么危害呢？最大的危害是隐性乳房炎能由于病情发展，变成显性乳房炎，乳汁出现絮状物（豆腐脑样子）；乳房组织肿胀，痛疼，甚至病牛发烧，不出奶。其次是奶牛得了隐性乳房炎产奶量下降，一般要减少乳量１０％左右。奶牛隐性乳房炎是怎样得的呢？隐性乳房炎由于现在检查方法有了，人们都开始重视这方面的问题，关于…     

奶牛隐性乳房炎研究进展

隐性乳房炎是危害奶牛的重要疾病之一,占乳房炎发病率的90%.本文总结了隐性乳房炎的发病情况、发生原因、诊断方法及预防措施.     

New Strategies to Prevent Mastitis

Bovine mastitis remains as the disease causing the biggest economic losses to the dairy industry, despite the intensive research and prevention measures at herd level carried out for decades. Antibiotics are widely used to combat mastitis, but focus should be shifted from treatment to more economical and efficient prevention. The bacteriological aetiology of mastitis has changed from contagious to environmental pathogens, which has reduced the efficacy of the traditional mastitis control strategies. Considerable progress in the understanding of epidemiology, immunology, diagnostics and pathogenesis of mastitis has been made. The modern molecular biological methods offer good possibilities for the research of the epidemiological and virulence aspects of bacteria, which may help in building‐up specific mastitis control strategies for dairy herds. Studies on the host response and relationship between somatic cell count and susceptibility to mastitis offer tools for genetic improvement of dairy cows. Biotechnological approaches for mastitis prevention are in the developmental stage, but many problems are associated, e.g. with vaccination of dairy cows against mastitis. Different methods of immunomodulation for the prevention of mastitis have shown promise in experimental trials, but the evidence is not yet enough to support commercial applications. Improving nutrition, housing and environment of dairy cattle are still crucial in the prevention of mastitis, especially during the most susceptible period after parturition. New milking techniques including robotic milking may provide better possibility for proper milking and improved udder health. Mastitis control should be part of the herd health programme in the dairy herds. In this paper, results from recent research and proposals for new prevention strategies in the field of mastitis are reviewed.     

预防奶牛乳腺炎的新策略

目前，对奶牛乳腺炎的流行病学、免疫学、诊断学和病因学等方面的研究已取得了很大进步，现代分子生物学方法为细菌流行病学和毒力研究提供了很好的工具，因而对于建立特异性的奶牛乳腺炎控制策略有很大的帮助。用生物技术方法预防奶牛乳腺炎目前还处于发展阶段，还有很多问题没有解决，例如预防奶牛乳腺炎的疫苗等问题，但不同的免疫调节方法在预防奶牛乳腺炎上已显示出有很好的前景。     

Mastitis and fertility disorders in cows

Udder inflammations, independently of significant losses in milk yield and alteration of its quality, can negatively affect cows' reproduction efficiency. Mastitis causes changes in many active constituents, both in milk and blood. Pathogenic changes in existing constituents and new active chemical compounds, generated during disease, can affect other organs, particularly the reproductive system and its mechanisms. Fertility disorders in mastitic cows are mostly connected with the activity of cytokines (especially TNF-alpha), cortisol, prostaglandin F2-alpha, reactive oxygen species (ROS), and classic inflammatory mediators. The successful treatment of mastitis as well as protection against udder infections should be considered important methods for prophylaxis of fertility disorders in cows. The first Polish trials indicated that injection of supportive drugs (antioxidants or lysozyme dimer or flunixin meglumine) to intramammarily treated cows can increase fertility in cows with mastitis.     

壳聚糖对乳房炎奶牛血清自由基代谢的影响

目的:探讨壳聚糖对乳房炎奶牛血清自由基代谢的影响。方法:选择产奶量、胎次和泌乳期相近,营养中等,乳房炎阴性6头,阳性30头,组成0(阴性对照组)、1(阳性对照组)和2、3、4、5组(试验组),每组6头。各组基础日粮相同。分别在各组基础日粮中添加壳聚糖0、0、10、20、40和80g/d·头。连续饲喂2周。分别于试验前(0周)、1周和2周采取血样,分离血清,测定血清SOD、CAT、GSH-Px活力和MDA、NO的含量。结果:饲喂壳聚糖后,各组血清SOD与GSH-Px活力显著升高,血清MDA含量显著降低。各试验组奶牛血清CAT活力均有升高的趋势,血清NO含量有降低的趋势,但差异均不显著(P>0·05)。结论:壳聚糖具有提高乳房炎奶牛血清SOD和GSH-Px活力,降低血清MDA的含量,提高机体抗氧化能力,改善血清自由基代谢水平和促进炎症康复的作用。但对血清CAT和NO基本没有影响。     

壳聚糖对乳房炎奶牛免疫功能的影响

选择6头健康奶牛和30头隐性乳房炎患牛,组成健康对照组、阳性对照组和壳聚糖1、2、3、4试验组,每组6头。分别在基础日粮中添加壳聚糖0 g、0 g、10 g、20 g、40 g和80 g/d·头,探讨壳聚糖对乳房炎奶牛免疫功能的影响。试验牛连续饲喂2周,分别于试验开始(0周)、1周和2周采取血样,测定血液WBC、LYM、TLYM、BLYM、PMN吞噬率和吞噬指数,血清CIC含量和隐性乳房炎乳阳性乳区/阳性牛的数量等指标。测定结果表明:饲喂壳聚糖后, WBC和LYM降低至临床健康牛的水平。活性TLYM和BLYM升高;PMN吞噬率和吞噬指数下降。血清CIC含量和隐性乳房炎乳阳性乳区/阳性牛数下降。表明壳聚糖具有抵抗炎症、清除血清CIC、调节PMN的吞噬活性,可增强机体的体液免疫和细胞免疫功能,促进隐性乳房炎奶牛的康复。     

Mastitis detection in dairy cows by application of neural networks

The aim of the present research was to investigate the usefulness of neural networks (NN) in the early detection and control of mastitis in cows milked in an automatic milking system. A data set of 403,537 milkings involving 478 cows was used. Mastitis was determined according to two different definitions: udder treatment or somatic cell counts (SCC) over 100,000/ml (1) and udder treatment or SCC over 400,000/ml (2). Mastitis alerts were generated by an NN model using electrical conductivity, milk production rate, milk flow rate and days in milk as input data. To develop and verify the model, the data set was randomly divided into training and test data subsets. The evaluation of the model was carried out according to block-sensitivity, specificity and error rate. When the block-sensitivity was set to be at least 80%, the specificities were 51.1% and 74.9% and the error rates were 51.3% and 80.5% for mastitis definitions 1 and 2, respectively. Additionally, the average number of true positive cows per day ranged from 1.2 to 6.4, and the average number of false negative positive cows per day ranged from 5.2 to 6.8 in an average herd size of 24 cows per day for the test data. The results for the test data verified those for the training data, indicating that the model could be generalized. The performance of the NN was not satisfactory. A decrease in the error rate might be achieved by means of more informative parameters.     

Mastitis detection in dairy cows by application of fuzzy logic

The aim of the present research was to develop a fuzzy logic model for classification and control of mastitis for cows milked in an automatic milking system. Recording of data was performed on the University of Kiel's experimental dairy farm “Karkendamm”. A data set of 403,537 milkings from 478 cows was used. Mastitis was determined according to three different definitions: udder treatments (1), udder treatment or somatic cell counts (SCC) over 100,000/ml (2) and udder treatment or SCC over 400,000/ml (3). Mastitis alerts were generated by a fuzzy logic model using electrical conductivity, milk production rate and milk flow rate as input data. To develop and verify the model, the data set was randomly divided into training data (284,669 milkings from 319 cows) and test data (135,414 milkings from 159 cows). The evaluation of the model was carried out according to sensitivity, specificity and error rate. If the block-sensitivity was set to be at least 80%, the specificities ranged between 93.9% and 75.8% and the error rate varied between 95.5% and 41.9% depending on mastitis definition. Additionally, the average number of true positive cows per day ranged from 0.1 to 7.2, and the average number of false negative positive cows per day ranged from 2.4 to 5.2 in an average herd size for the test data of 39.7 cows/day. The results of the test data verified those of the training data, indicating that the model could be generalized.

Fuzzy logic is a useful tool to develop a detection model for mastitis. A noticeable decrease in the error rate can be made possible by means of more informative parameters.     

奶牛金黄色葡萄球菌乳房炎菌苗佐剂研究现状

金黄色葡萄球菌是引起奶牛乳房炎的重要致病菌。近年来 ,科学工作者对于预防奶牛金黄色葡萄球菌乳房炎的疫苗进行了大量研究 ,但由于金黄色葡萄球菌存在着荚膜的原因 ,疫苗效果不理想 ,需要佐剂提高疫苗的免疫原性。目前研究的佐剂主要有弗氏佐剂、氢氧化铝、细胞因子、微球、人参提取物及其皂甙Rb1等。其中弗氏佐剂、氢氧化铝容易引起局部副作用使其应用受到限制 ,而细胞因子、微球和人参皂甙等佐剂因其效果确实 ,安全性好值得应用推广。     

防治环境性病原菌引起的乳腺炎

1前言 在美国,因奶牛乳腺炎被淘汰的约占所有淘汰乳用母牛的26．5％;法国奶牛整个第一泌乳期临床乳腺炎为26．3％;在芬兰、挪威、瑞典乳房健康问题分别为淘汰母牛的39％、19％和22％。目前发现约有150多种病原体可引起奶牛乳腺炎,其中有球菌、杆菌、真菌或酵母菌、霉形体、病毒等。包括：①传染性病原菌,如无乳链球菌、金黄色葡萄球菌、霉形体等,可在乳区和牛群中传播流行;