Bovine mastitis therapy and why it fails

Treatment of bovine mastitis depends on the cause, the clinical manifestation and the antibiotic susceptibility of the agent. Mastitis therapy is commonly unsuccessful owing to pathological changes that occur in the udder parenchyma as a result of the inflammatory reaction to mastitogenic bacteria, pharmacokinetic properties of antimicrobial mastitis drugs, mastitogenic bacterial and related factors, and poor animal husbandry and veterinary interventions.     

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。     

Prevalence and Aetiology of Mastitis in Cows from Two Major Ethiopian Dairies

The study was undertaken to determine the aetiology and prevalence of mastitis in hand-milked cows (n = 186) in two major Ethiopian dairies. The California Mastitis Test and culturing for bacteria revealed that 21.5% of the cows were clinically infected and 38.2% had subclinical mastitis. Most mastitis pathogens isolated from milk samples testing positive by the California Mastitis Test were Gram-positive cocci. Staphylococci constituted 57% of the isolates, of which the predominant cause of bovine mastitis was Staphylococcus aureus (40.5%). Other mastitis pathogens isolated include streptococci (16.5%), coliforms (9%) and corynebacteria (5%). Retrospective analysis of farm records indicated that mastitis was the second most important cause of culling and accounted for 27% of the cows removed from these two dairies.     

中草药防治奶牛乳房炎的研究进展

奶牛乳房炎是危害奶牛养殖业常见的疾病之一,尤其是隐性乳房炎对奶牛生产造成了巨大的经济损失,文章对奶牛乳房炎的发病情况和致病机理,传统治疗方法存在的缺点和中草药防治奶牛乳房炎的进展作一综述。     

Cell free mitochondrial DNA in serum and milk associated with bovine mastitis: a pilot study

Mastitis is inflammation of mammary gland affecting all the species of domestic animals. Fragments of the mitochondrial genome released from dying cells are considered surrogate markers of mitochondrial injury. We hypothesized that bovine mastitis would be associated with increased cell free mitochondrial DNA (mtDNA) content in serum and milk. Milk and serum samples were collected from sub-clinical mastitic and normal animals. Mastitis was confirmed by California mastitis test and bacterial isolation. Oxidative stress, nitric oxide and inflammatory cytokines were also estimated. Real time polymerase chain reaction was conducted in serum and milk from sub-clinical mastitic animals and compared with healthy animals targeting the mtDNA genes cytochrome b. Mastitis animals showed higher oxidative stress markers and nitric oxide along with higher level of inflammatory cytokines. Cell free mtDNA was significantly higher in serum and milk of mastitic animals comparing to that of healthy control. The higher cell free relative mtDNA content in mastitis animals indicates injury to the mammary epithelial cells and thereby releasing the mtDNA in the milk and blood. This mtDNA may be a bio-marker of oxidative stress and tissue injury in bovine mastitis.     

Aetiology of clinical mastitis in six Somerset dairy herds.

Clinical mastitis was monitored in six Somerset dairy herds for one year. The herds all had three-month geometric mean bulk milk somatic cell counts of less than 250,000 cells/ml. Escherichia coli was the predominant pathogen isolated on all the farms and in all months of the year. Environmental pathogens accounted for 61.4 per cent of all cases of clinical mastitis and for 79.3 per cent of the mastitis cases in which an aetiological agent was identified. The mean annual incidence was 41.6 cases per 100 cows (range 14 to 75). Affected cows suffered a mean of 1.5 cases and 16.4 per cent of quarters suffered at least one repeat case. Mastitis due to E. coli was more severe than mastitis due to other causes and it tended to be more severe in early lactation and during the housing period. Mastitis was significantly more severe (grades 2 and 3) in the herd with the lowest bulk milk somatic cell count and in the herd which was kept indoors throughout the year than in the other four herds. Mastitis was fatal in 2.2 per cent of cases and resulted in the death of 0.6 per cent of the lactating cows.     

Indicators of inflammation in the diagnosis of mastitis

Mastitis affects the quality of milk and is a potential health risk for the other cows. In a well managed dairy herd, in addition to clinical mastitis, subclinical mastitis should be efficiently detected. Bacteriological sampling is not feasible as a routine test to identify subclinical mastitis, and indirect tests of mastitis are more suitable for selecting cows with intramammary infections for subsequent bacteriological sampling. Mastitis affects the composition of milk, and the degree of changes depends on the infecting agent and the inflammatory response. Indicators of inflammation in the milk which can be determined using rapid, reliable and easy routine techniques, can be used for the early detection of mastitis. The measuring of the somatic cell count in milk is the standard method, but the analysis technique is problematic for routine use in herds. The most promising parameters for monitoring subclinical mastitis are milk N-acetyl-beta-D-glucosaminidase activity, lactose, and electrical conductivity along with some other indicators such as optical and milk flow measurements, preferably with an inter-quarter evaluation included in the test. Acute phase proteins, haptoglobin and serum amyloid A, are also potential candidates for mastitis monitoring. New mastitis detection systems which can be adapted into on-line use are urgently needed, since dairy units are growing bigger and automatic milking systems are being taken into use.     

NF-κB信号通路调控奶牛乳腺炎的分子作用机制

乳腺炎通常是由微生物感染引起的乳腺炎症反应,是奶牛最常见的疾病之一,可导致牛奶产量及品质下降,奶牛利用年限减少,严重地影响着牧场的经济效益。近年来,学者们在奶牛乳腺炎分子调节机制方面开展了大量研究,发现NF-κB及其信号通路可参与调控多个免疫相关基因的表达,在细胞炎症反应和免疫应答等过程起关键性作用,也是奶牛乳腺炎研究的热点。本文阐述了奶牛乳腺炎的病因和病理变化,以及NF-κB信号通路与机体免疫的关系,并重点综述了mRNA、非编码RNA（miRNA、lncRNA和circRNA）及生物活性物质通过NF-κB信号通路调控奶牛乳腺炎的最新研究进展,为奶牛乳腺炎的分子调控网络解析、抗乳腺炎分子育种与生物活性药物研发提供参考。     

国内外临床型乳房炎发生现状及其危害

乳房炎是国内外奶牛生产中造成经济损失最大的疾病之一,作者就国内外奶牛临床型乳房炎的发生概况,致病菌,以及经济损失三方面进行了综述,旨在为改进奶牛场管理、加强乳房炎控制提供科学依据。     

Lactation-related mammary gland pathologies—A neglected emergency in the bitch

Mastitis is a common reproductive disorder in bitches, reaching a prevalence of 0.71%. Mastitis has a wide range of forms, from asymptomatic to severe gangrenous mastitis that can lead to septic shock and death of the bitch and nurslings. However, most of the time it is overlooked, undiagnosed or mistreated. The present systematic review was performed to revise and summarize the existing knowledge related to this disorder, including diagnosis, treatment and prevention.     

中草药防治奶牛乳房炎的研究概况

奶牛乳房炎是奶牛最常见的疾病之一。严重制约着奶牛业的发展，本文主要对我国应用中草药防治奶牛乳房炎的各种方法和防治机理进行了综述。对中草药防治奶牛乳房炎的前景进行了展望。认为中草药在治疗奶牛乳房炎方面具有巨大的潜力。     

Clinical findings and pathological changes in Histophilus ovis infections of sheep

The Gram-negative pleomorphic bacterium Histophilus ovis was incriminated as the cause of natural cases of epididymitis in rams, polyarthritis in lambs, mastitis and abortion in ewes. Epididymitis was sporadic in occurrence, unilateral in distribution and varied from acute to chronic in degree. Polyarthritis affected recently born lambs and resulted in acute lameness and subsequent debility. Mastitis was rare in occurrence, unilateral in distribution, acute and gangrenous in type. Abortion was also rare and manifested by a specific haemorrhagic placentitis. These four conditions were reproduced experimentally. The clinical, pathological and histopathological changes associated with field and experimental cases are described.     

A review of the factors affecting the costs of bovine mastitis

Mastitis is one of the most prevalent production diseases affecting the dairy cattle industry worldwide. Its occurrence is associated with direct and indirect losses and expenditures. When estimating the cost of mastitis to the dairy industry the cost of the control programmes must be added. The direct losses of mastitis are the only costs obvious to the farmer. The difference between the costs of mastitis on one side and the benefits of mastitis control on the other side will give us a picture of the economic efficacy of the mastitis control programme. Continuing education of the farmer is needed for better mastitis control programmes. This article is an attempt to review briefly all relevant factors included in the economics of bovine mastitis and to illustrate the authors' view of some of the costs.     

奶牛乳房炎防治研究进展

奶牛乳房炎是危害奶牛养殖业常见的疾病之一.本文对控制奶牛乳房炎的经济意义、预防和治疗乳房炎及乳房炎防治研究方向等方面进行简要综述,为深入研究奶牛乳房炎的综合防治提供资料.     

奶牛乳腺炎抗性候选基因多态性研究进展

奶牛的乳腺炎是一种极其复杂的疾病,是影响奶牛产业发展的一个重要因素。对奶牛乳腺炎抗性的研究有助于选育出有高抗性的奶牛群体,提高奶产品的数量和质量,并且可以减少抗生素的使用。近年来,随着生物信息学、分子育种技术和基因组学的发展,为奶牛的乳腺炎抗病育种提供的新的前景。本文主要介绍了牛锌指蛋白313基因、前脑锌指蛋白基因、T...     

Mastitis control programme in the developing dairy industry of tropical lowland Bolivia

Mastitis is an important disease in developing dairy industries. This paper describes a commercial mastitis control programme in Santa Cruz, Bolivia, based upon the five-point mastitis control plan and bulk tank somatic cell count (BTSCC) monitoring. Twelve farms which participated on the programme for 6 years are considered. Mean annual BTSCC fell steadily from 1200000 cells/ml to 461000 cells/ml over this time. This progressive improvement was probably a result of increasing use of and attention to detail in mastitis control practices. The control of subclinical mastitis improved in both hand-milked and machine-milked herds, though hand-milked herds consistently produced milk of higher BTSCC. The mastitis programme did not appear to influence the incidence of clinical mastitis. The paper concludes that a simple mastitis programme based on the five-point plan and BTSCC monitoring can be commercially implemented and effectively control subclinical mastitis in a tropical, developing country.     

奶牛主组织相容性复合物及其在奶牛抗乳房炎分子育种中的应用

奶牛乳房炎是一极为复杂的疾病,对乳房炎的控制也是一系统工程.除了传统的防治手段外,对抗乳房炎性状候选基因或遗传标记的研究已成为乳房炎抗性遗传育种的热点.牛主要组织相容性复合物(MHC)是一类与免疫功能密切相关的转膜蛋白.由于其在免疫系统中发挥着极其重要的作用,又与家畜疾病的抗性和易感性之间有着非常密切的关系,使之成为在抗乳房炎性状的分子育种领域倍受关注的基因之一.作者在论述了奶牛抗乳房炎分子育种研究现状的基础上,重点阐述了MHC的结构、功能、作用及其与乳房炎的关系,指出了对MHC与乳房炎关系研究的重要意义和发展前景.     

Pharmacokinetics and pharmacodynamics of intramammary cefquinome in lactating goats with and without experimentally induced Staphylococcus aureus mastitis

Values for pharmacokinetic variables are usually obtained in healthy animals, whereas drugs are frequently administered to diseased animals. This study investigated cefquinome pharmacokinetics in healthy goats and goats with experimentally induced mastitis. Five adult lactating goats received 75 mg of cefquinome intramammary infusion using a commercially available product into one udder half in healthy goats and goats with clinical mastitis that was induced by intracisternal infusion of 100 cfu of Staphylococcus aureus ATCC 29213 suspended in 5 ml of sterile culture broth. Cefquinome concentrations were determined in plasma and skimmed milk samples using high‐performance liquid chromatography (HPLC). Pharmacodynamics was investigated using the California Mastitis Test and pH of milk. Experimentally induced mastitis significantly increased the California Mastitis Test score and pH, and decreased the maximal cefquinome concentration and shortened the half‐life in milk when compared to healthy goats. In conclusion, mastitis facilitated the absorption of cefquinome from the mammary gland of lactating goats and induced marked changes in milk pH, emphasizing the importance of performing pharmacokinetic studies of antimicrobial agents in infected animals.     

奶牛乳房炎研究进展

奶牛乳房炎是造成奶牛养殖业经济损失的重要传染病之一,随着我国奶牛养殖业的不断发展,牛奶产量的不断提升,奶牛乳房炎的发病率也呈上升趋势,尤其是隐性乳房炎给奶牛养殖场带来的经济损失更是十分巨大。基于此,本文综述了奶牛乳房炎的病因、发病机理、危害、临床症状、检查方法以及治疗手段,以期为奶牛养殖场预防奶牛乳房炎的发生提供理论基础。     

微生态制剂防制奶牛乳房炎的研究进展

乳房炎是奶牛业最常见的疾病之一,该病不仅给奶牛业造成巨大经济损失,且严重影响牛奶的质量。微生态制剂因其安全、绿色,有望替代抗生素而被广泛应用。文章对奶牛乳房炎的发病机制、微生态制剂防制奶牛乳房炎的作用机理及国内外对微生态制剂防制奶牛乳房炎的研究进展作一综述。