Effects of Clinical Mastitis on Ovarian Function in Post-partum Dairy Cows

Mastitis-induced ovarian abnormalities were studied in a field trial. At 1-3 day after calving, > or = 2 parity cows not affected with chronic recurrent mastitis and yielding < 400,000/ml somatic cell count (SCC) individual milk in the previous lactation, were enrolled in the study. Thereafter milk samples were collected three times weekly for 95-100 day for progesterone (P4) assay. Individual P4 profiles were used to monitor ovarian cyclicity. When mastitis was diagnosed in the first 80 day post-partum (pp), clinical signs were recorded and scored, and aseptic milk samples were taken to identify the mastitis pathogens. Depending on the isolated pathogens the cows were blocked into one of the three sub-groups affected by either Gram-positive (GP), or Gram-negative (GN) bacteria, or of those with no detected pathogens (NDP). Cows suffering from any type of mastitis between days 15 and 28 (n = 27) showed a delay in the onset of ovarian cyclicity, and estrus was postponed compared to cows affected during the first 14 day pp (n = 59) and controls (n = 175) (38.6 +/- 2.3 vs 33.4 +/- 2.1 and 32.0 +/- 1.0 day, respectively, for onset of ovarian cyclicity and 90.7 +/- 2.5 vs 80.2 +/- 2.8 and 83.9 +/- 2.1 day, respectively, for estrus; both p < 0.05). The percentage of cows ovulating by day 28 was lower in those affected by mastitis between days 14 and 28 compared to cows between days 1 and 14 and controls (22.2% vs 47.5 and 50.3%, respectively; p < 0.05). A significantly higher rate of premature luteolysis was observed in GN + NDP compared to GP mastitis and healthy cows (46.7% vs 8.3 and 2.0%, respectively; p < 0.001). If the mastitis outbreak occurred during the follicular phase, the duration of this cycle segment was lengthened in GN + NDP mastitis compared to GP mastitis and healthy cows (10.8 +/- 0.9 vs 7.9 +/- 0.1 and 7.2 +/- 0.1, respectively; p < 0.001). The results indicate that mastitis can affect the resumption of ovarian activity in pp dairy cows. Mastitis may also impair reproduction also in cyclic cows: this effect can be the consequence of premature luteolysis or a prolonged follicular phase.     

围产期和泌乳早期奶牛的若干营养策略探讨

通过对围产期与泌乳早期奶牛营养代谢特征及其与生产性能,繁殖率和健康关系的分析,作者提出改善能量负平衡,调整日粮营养组分,补充维生素和矿物质等营养调控手段,是降低奶牛代谢病发生率,改善繁殖性能,提高生产性能的有效策略.     

Mastitis in Post-Partum Dairy Cows

Transition from the dry period to lactation is a high risk period for the modern dairy cow. The biggest challenge at that time is mastitis. Environmental bacteria are the most problematic pathogens around parturition. Coliforms are able to cause severe infections in multiparous cows, and heifers are likely to be infected with coagulase-negative staphylococci. During the periparturient period, hormonal and other factors make the dairy cows more or less immunocompromised. A successful mastitis control programme is focused on the management of dry and calving cows and heifers. Clean and comfortable environment, proper feeding and adequate supplementation of the diet with vitamins and trace elements are essential for maintaining good udder health. Strategies which would enhance closure of the teat canal in the beginning of the dry period and would protect teat end from bacteria until the keratin plug has formed decrease the risk for mastitis after calving. Dry cow therapy has been used with considerable success. Yet, a selective approach could be recommended rather than blanket therapy. Non-antibiotic approaches can be useful tools to prevent new infections during the dry period, in herds where the risk for environmental mastitis is high. Vaccination has been suggested as a means to support the immune defence of the dairy cow around parturition. In some countries, implementation of Escherichia coli core antigen vaccine has reduced the incidence of severe coliform mastitis after calving.     

泌乳早期奶牛的饲养与保健

本文结合笔者多年的实践经验,对奶牛泌乳早期的饲养、挤奶方法、兽医保健、繁育保健等几个方面加以总结,供广大养殖户参考。     

蛋氨酸锌和亚硒酸钠维生素E对奶牛泌乳前期乳腺炎的预防效果

本研究试图通过对昆明地区等规模化场在泌乳前期奶牛日粮中添加蛋氨酸锌600mg/kg、亚硒酸钠维生素E70mg/kg来预防乳腺炎,结果表明：与对照组相比,处理组产后90d内平均产奶量每头每日提高1.5kg,增加8.43%,差异极显著（P〈0.01）;产后15～90d内隐性乳腺炎的阳性率减少13个百分点,差异极显著（P〈0.01）;牛奶中SCC减少15.4万/mL,降低33.4%,试验组与对照组差异极显著（P〈0.01）。结果表明日粮中添加蛋氨酸锌和亚硒酸钠维生素E对昆明地区泌乳前期奶牛乳腺炎有较好的预防效果。     

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。     

奶牛乳房炎疫苗研究进展

乳房炎是奶牛最常发生的疾病之一,降低了牛奶的产量和质量,严重时会致使奶牛淘汰甚至死亡,给奶牛养殖业造成巨大的经济损失。基于疫苗预防安全、高效、无毒等特点,奶牛乳房炎疫苗受到广大学者的重视。论文对奶牛乳房炎的免疫机制,奶牛乳房炎灭活苗、活苗、亚单位疫苗、载体疫苗和核酸疫苗的研究进展及疫苗研发存在的难点、解决方案和发展前景进行了综述,以期对奶牛乳房炎疫苗研究有一定的借鉴作用。     

奶牛乳房炎疫苗的研究进展

乳房炎（Mastitis）是乳腺受到物理、化学刺激，尤其是微生物侵袭所发生的一种炎性变化，给奶牛养殖业造成了巨大的经济损失。引起奶牛乳房炎的常见致病菌有金黄色葡萄球菌属、链球菌属、大肠杆菌属等约140多种，当外界病原菌进入乳房，突破奶牛的免疫防御体系，定植，感染，就会形成乳房炎。     

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。     

奶牛乳房炎的综合防制

奶牛乳房炎是危害并制约奶牛业发展的常见病,因此,加强对奶牛乳房炎的发病机制和综合防控的研究,减少损失,在奶牛生产实践中具有重大意义。本文分析了奶牛乳房炎的发病机理、临床症状及实验室检测方法,以快速确诊该病;同时提出了综合防制措施,及时防控疾病的发生与蔓延,为提高奶牛养殖效率和促进动物生产提供理论依据和参考。     

奶牛真菌性乳房炎研究进展

真菌性乳房炎,主要是通过真菌污染的灌注导管、注射器或多次乳房灌注使真菌医源性地进入乳房而引起的.因此,真菌性乳房炎几乎总是继发于治疗不当的急性细菌性乳房炎,并且在抗生素存在的情况下部分真菌生长旺盛:连续使用抗生素或联合使用抗生素来治疗这种"耐药的"感染只会加剧真菌感染 [1,2].     

丙三醇对泌乳早期奶牛采食量、泌乳性能和代谢产物的影响

选用36头经产奶牛,根据泌乳期、上一泌乳期305天产奶量和预产期,采用随机区组设计分为4组,研究丙三醇（0、100、200和300 g.d-1）对泌乳早期奶牛采食量、泌乳性能、体质量变化、能量平衡、血液代谢产物和尿酮浓度的影响。结果表明：日粮添加丙三醇对奶牛的采食量、产奶量、乳蛋白率、乳糖率和乳干物质率无显著影响,200和300 g.d-1组饲料转化效率显著高于对照组（P〈0.05）,300 g.d-1组乳脂率显著低于对照组和100 g.d-1组（P〈0.05）。添加丙三醇后,和300 g.d-1组血浆葡萄糖浓度显著高于对照组（P〈0.05）,而血浆游离脂肪酸（NEFA）浓度显著低于对照组（P〈0.05）,300 g.d-1组β-羟丁酸浓度显著低于对照组（P〈0.05）;和300 g.d-1组尿酮浓度显著低于对照组（P〈0.05）。添加丙三醇200和300 g.d-1均显著改善了泌乳早期奶牛能量负平衡,减少了体质量下降。     

复方中草药添加剂对奶牛隐性乳房炎发病率和泌乳性能的影响

为了解复方中草药添加剂对奶牛隐性乳房炎的防治效果和对奶牛泌乳性能的影响,对陕西省某规模化牛场2014年1月至2019年12月奶牛群改良(DHI)检测数据进行统计分析,对比该牛场自2016年10月使用复方中草药饲料添加剂前后奶牛隐性乳房炎发病率、305 d产奶量、日产奶量、泌乳持续力、泌乳高峰日、产犊间隔等的变化情况.结...     

An Outbreak of Pseudomonas Mastitis in Dairy Cows

An outbreak of mastitis in a dairy herd is described in which the causative organism was Pseudomonas aeruginosa. Cases occurred either in dry cows or in animals which had very recently calved. The fact that all four quarters were involved is a very strong indication that the bacteria had been introduced in the dry cow therapy.     

奶牛隐性乳房炎的调查分析

在2004年3月-5月间，我们对内蒙古西部地区两个奶牛养殖场和一个奶牛养殖专业村共200头泌乳期奶牛进行隐性乳房炎调查诊断，现将调查情况报告如下。     

奶牛乳房炎的发病机制与预防措施

奶牛乳房炎和自身抗病力有关,受致病菌感染、外界环境刺激、日粮营养搭配和饲养管理等因素的影响,具有发病率高、传播性强、危害性高的特点,若诊断不及时或治疗不当很容易影响奶牛的泌乳性能和乳品质.对奶牛乳房炎发病机制进行详细分析,并提出防治方法,以期降低发病率,促进奶牛养殖业的健康发展.