新诊断标准下妊娠期糖尿病高危因素研究

目的:调查新诊断标准下国内妊娠期糖尿病(Gestational diabetes mellitus GDM)的发病情况,分析影响GDM发生的高危因素,为新标准下国内GDM孕妇临床早期管理、诊断和干预提供理论依据。方法:对2011年1月至2011年9月我院接受产前建卡检查的所有孕妇1152例进行临床资料的收集及回顾性研究,排除孕前糖尿病患者16例,采用GDM诊断新标准进行"一步法"诊断,收集包括年龄、孕产次、体质指数(body mass index BMI)、糖尿病家族史、多囊卵巢综合征等13种影响GDM发生的危险因素,并综合分析。结果:新标准下GDM检出率为10.39%(118/1136)2)单因素分析结果发现年龄≥35岁(X2=10.2814,P=0.0013)、肥胖(孕前BMI≥28kg/m2()X2=36.2384,P<0.0001)、多囊卵巢综合征(X2=20.6725,P<0.0001)、糖尿病家族史(X2=7.8783,P=0.0050)在GDM组与非GDM组有统计学差异,多因素逐步Logistic回归分析肥胖(OR=7.546 95%CI=2.356~20.129 P=0.0002)、多囊卵巢综合征(OR=6.342 95%CI=1.783~16.329,P=0.0019)、年龄(OR=3.021 95%CI=0.983~6.459 P=0.0108)、糖尿病家族史(OR=2.43895%CI=0.612~5.231 P=0.0256)为GDM的高危因素。结论:新标准下报告GDM检出率为10.39%。肥胖、多囊卵巢综合征、年龄、糖尿病家族史为影响GDM发生的高危因素。加强GDM筛查并对具有高危因素的妊娠期妇女早期诊断,早期干预、早期管理可改善妊娠结局,提高人口素质。     

细菌性阴道病合并人乳头瘤病毒感染的 影响因素

目的分析细菌性阴道病(BV)合并人乳头瘤病毒(HPV)感染的影响因素,为预防BV合并HPV感染的发生提供参考依据。方法收集2017年2月至2017年12月就诊于天津中医药大学第一附属医院符合标准的妇女,观察组为HPV合并BV感染的患者,对照组为健康妇女,通过问卷调查研究两组妇女一般情况的差异性。结果共纳入204名研究对象,其中观察组78例,对照组126例。观察组中HPV感染以单型感染居多,共46例,占59.0%;观察组以高危型别感染居多,共70例,占89.7%。通过单因素回归分析可得年龄≥40岁(P=0.000,OR=3.795)、初次性生活年龄20岁(P=0.011,OR=2.914)、性伴侣数≥2(P=0.036,OR=2.005)、每周性生活次数2次(P=0.029,OR=1.927)、妊娠次数≥2(P=0.000,OR=2.920)是导致HPV合并BV感染的影响因素。多因素非条件logistic回归分析结果显示年龄≥40岁(P=0.001,OR=3.880)、初次性生活年龄20岁(P=0.018,OR=3.127)、性伴数≥2个(P=0.021,OR=2.595)、妊娠次数≥2(P=0.030,OR=2.303)是HPV合并BV的独立影响因素。结论年龄大、初次性生活年龄小、性伴侣个数多、妊娠次数多为HPV合并BV的独立危险因素,临床中应做好知识普及工作,预防HPV合并BV的发生。     

外科ICU 中心静脉导管相关血流感染的回顾性病例对照研究

目的:了解外科ICU中心静脉导管相关血流感染(CRBSI)的发病率、病原菌分布及相关危险因素,为临床预防和经验性治疗提供依据。方法:回顾性调查我院外科ICU 2010年1月～2011年8月的中心静脉导管置管病例,根据血培养和导管培养结果分为CRBSI组和非CRBSI组,统计CRBSI的发病率、致病菌;比较CRBSI组与非CRBSI的临床资料,应用多因素Logistic回归分析筛查相关危险因素。结果:共收集249例中心静脉置管病例,CRBSI发病率为8.41例次/千导管日,病原菌分布为G+菌4例,G-菌9例,真菌8例。Logistic回归分析显示导管留置时间(OR 3.298,95%CI 1.070~10.168,P=0.038)、APACHEII评分(OR 1.137,95%CI 1.067~1.213,P=0.000)、完全胃肠外营养(OR 1.117,95%CI 1.023~1.219,P=0.014)是CRBSI的独立危险因素。结论:导管留置时间、APACHEII评分、完全胃肠外营养是发生CRBSI的独立危险因素。     

重症监护病房患者多重耐药鲍曼不动杆菌感染及 病死危险因素分析

目的探讨重症监护病房患者多重耐药鲍曼不动杆菌(MDRAb)感染的危险因素及MDRAb感染患者病死的危险因素,为防治MDRAb提供依据。方法回顾性分析2014年1月至2017年10月遂宁市中心医院重症监护病房197例鲍曼不动杆菌(Ab)感染患者,采用病例对照研究,根据抗生素敏感实验结果,将111例MDRAb感染者作为病例组,86例非MDRAb感染者作为对照组,收集其人口学资料、感染前的临床资料和实验室数据,应用单因素分析及多因素Logistic回归分析其感染的危险因素。同时将病例组分为病死组与存活组,分析其病死危险因素。结果 MDRAb检出率为56.35%。单因素Logistic分析显示,ICU停留时间、使用抗生素7d、使用喹诺酮类抗生素、有创通气和胃管插管可能是MDRAb感染的危险因素(P0.05)。多因素Logistic回归分析显示,使用抗生素7d(OR=2.338,95%CI:1.252~4.368)、使用喹诺酮类抗生素(OR=3.703,95%CI:1.665~8.234)、有创通气(OR=4.356,95%CI:1.695~11.192)是MDRAb感染的独立危险因素。单因素Logistic分析显示,年龄、高血压、血红蛋白量、昏迷可能是MDRAb感染患者病死的危险因素。多因素Logistic回归分析显示,高血压(OR=5.185,95%CI:2.012~13.361)、血红蛋白量(OR=0.976,95%CI:0.957~0.996)和昏迷(OR=4.061,95%CI:1.517~10.873)是MDRAb感染患者病死的独立危险因素。结论使用抗生素7d、使用喹诺酮类抗生素、有创通气是MDRAb感染的独立危险因素;高血压、血红蛋白量、昏迷是MDRAb感染患者病死的危险因素。     

青年卒中后抑郁/焦虑危险因素logistic回归分析

目的:探讨青年卒中患者抑郁/焦虑发生的危险因素,为制定科学的管理策略提供依据。方法:选择2012年7月至2013年7月我院收治的69例青年卒中患者,采用《Hamilton抑郁量表(HAMD)》和《Hamilton焦虑量表(HAMA)》筛选出抑郁/焦虑病例作为病例组,其他病例作为对照组,通过多因素非条件Logistic回归模型分析青年卒中后抑郁/焦虑产生的危险因素。结果:69例青年卒中病人中,抑郁、焦虑的发生率分别约26.0%和36.2%。多因素Logistic回归分析显示NIHSS评分(OR值5.002,95%CI为4.015~6.023)、幕下病变(OR值0.466,95%CI为0.145~1.505)、伴随基础疾病(OR值0.093,95%CI为0.008~1.129)是青年卒中后抑郁/焦虑出现的危险因素。结论:对青年卒中患者要积极控制基础疾病,重视幕下病变和严重残疾,有助于预防及早期识别卒中后抑郁/焦虑的产生。     

妊娠糖尿病饮食相关危险因素分析（英文）

目的:通过分析妊娠糖尿病患者与正常孕妇的饮食行为,探讨妊娠糖尿病发病饮食相关的危险因素,为孕期妇女提供科学合理膳食指导。方法:采用多阶段连续等比例抽样,选取确诊GDM的孕妇150例为病例组,同期就诊非GDM孕妇150例为对照组,利用24小时膳食回顾法进行饮食行为和一般情况的问卷调查。采用Logistic回归筛选GDM饮食相关危险因素。结果:多因素Logistic回归分析显示,怀孕年龄(OR=1.157)、孕前BMI(OR=1.780)、糖尿病家族史(OR=2.448)、产次(OR=1.157)、总能量、水果摄入量(OR=4.109)、豆类(OR=0.998)与妊娠糖尿病发生相关(OR=0.998)。采用多变量模型具体分析水果的摄入量,同时调整与妊娠糖尿病发生的相关因素结果显示:与水果摄入量小于200 g/d相比,水果的摄入量200~400 g/d,400~600 g/d和超过600 g/d其OR值分别为0.38、2.48、2.63(P0.01)。结论:除高龄、肥胖、糖尿病家族史等妊娠糖尿病高危因素外,饮食行为与GDM存在一定的相关性。针对高危人群早期干预,同时对孕期妇女进行科学合理的饮食指导,调整饮食结构,控制食物摄入量,以减少GDM的发病。     

浆细胞性乳腺炎动物模型制备及模型效果评价的研究进展

浆细胞性乳腺炎(plasma cell mastitis,PCM)为较常见乳腺疾病,国内发病率与日俱增.PCM主要发生于非哺乳期中年女性,其临床表现及病理改变复杂,治疗手段亦多样化.目前PCM主要集中于临床观察研究,病理过程、发病机制尚不完全明确,基础研究严重不足,因此制备PCM动物模型并进行有效的评估对深入研究分子机...     

非哺乳期乳腺炎的临床治疗探讨

目的:观察抗生素联合泼尼松双联药物冲击方法治疗非哺乳期急性乳腺炎的临床疗效。方法:选取本院乳腺外科2016年6月至2017年6月收治的105例非哺乳期急性乳腺炎患者作为观察对象,依照诊治顺序将其随机分为观察1组、观察2组以及对照组,每组35例患者。对照组给予口服左氧氟沙星,0.5 g/次,qd;观察1组在对照组的治疗方法中加用醋酸泼尼松片强的松20mg,qd;观察2组在对照组的治疗方法中加用醋酸泼尼松片强的松40 mg,qd,三组均以14 d为一疗程。治疗1个疗程后,评价和比较各组治疗效果、血细胞数、好转时间、痊愈时、住院时间及不良反应的发生情况。结果:治疗后,观察1组、观察2组和对照组有效率分别为82.86%、97.14%和60.00%,观察2组有效率显著高于观察1组和对照组(P0.05)。三组患者治疗后白细胞,中性粒细胞,淋巴细胞均较治疗前明显下降(P0.05),且观察2组以上指标显著低于观察1组和对照组(P0.05)。观察2组的好转时间、痊愈时间及住院时间均明显短于观察1组和对照组(P0.05),而观察1组的好转时间、痊愈时间及住院时间明显短于对照组(P0.05)。观察1组出现1例轻微胃肠道反应,1例胸闷,不良反应总发生率为5.71%(2/35);观察2组出现1例轻微胃肠道情况,不良反应总发生率为2.86%(1/35);对照组2例患者发生胸闷,1例患者出现轻微胃肠道不适,1例患者出现眩晕,不良反应发生率为11.43%(4/35),三组不良反应发生率比较差异均无统计学意义(P0.05)。结论:口服抗生素联合泼尼松治疗非哺乳期急性乳腺炎患者能提高临床疗效,且加大泼尼松口服剂量可进一步提高临床有效率,控制炎性进展,缩短痊愈时间。     

糖尿病视网膜病变患者多次住院的影响因素分析

目的:探讨糖尿病视网膜病变(DR)患者多次住院(住院次数≥2)的影响因素。方法:以2型糖尿病(DM)并因糖尿病视网膜病变(DR)相关并发症多次住院(住院次数≥2)的患者为实验组,对照组为非糖尿病多次因眼科相关疾病住院(住院次数≥2)患者。比较两组患者在第二次住院时的发病年龄、空腹血糖(fasting blood glucose,GLU)、糖化血清蛋白(glycated serum protrin,GSP)、丙氨酸氨基转移酶(Alanine aminotransferase,ALT)、天冬氨酸氨基转移酶(aspartate aminotransferase,AST)、肌酐(creatinine,Cr)、尿素(urea)、总胆汁酸(total bile acid,TBA)、血清尿酸(uric acid,UA)、甘油三酯(triglycetide,TG)、胆固醇(cholesterol,Ch)、体质指数(body mass index,BMI)等。结果:单因素分析结果显示入院时血糖、糖化血清蛋白、血清尿酸、甘油三酯、胆固醇与DR患者多次住院(住院次数≥2)显著相关(P均≤0.01)。多因素Logistic回归分析显示:空腹血糖(P=0.038;95%CI:1.101~26.325)、糖化血清蛋白(P=0.003;95%CI:1.017~1.082)、尿酸(P=0.167;95%CI:0.994~1.032)、甘油三脂(P=0.023;95%CI:1.774~2228.179)、胆固醇(P=0.029;95%CI:1.317~166.317)水平是DR患者多次住院(住院次数≥2)的独立危险因素。结论:空腹血糖、糖化血清蛋白、尿酸、甘油三脂和胆固醇是DR患者多次住院(住院次数≥2)的独立危险因素。     

念珠菌血症的危险因素和预后分析

目的了解念珠菌血症的临床特点、分布及预后危险因素。方法回顾性调查2012年1月至2014年5月浙江大学医学院附属第一医院所有血培养念珠菌阳性的患者资料,分析其临床特征、治疗和预后等,采用χ2检验或Fisher精确概率法进行预后单因素分析,采用多元Logistic回归进行预后多因素分析。结果 97例念珠菌血症患者入选,其中男性64例,女性33例,平均年龄（59.6±16.8）岁。包括白色念珠菌51例（52.6%）,非白色念珠菌46例（47.4%）,非白色念珠菌中热带念珠菌17例（17.5%）、近平滑念珠菌12例（12.4%）、光滑念珠菌7例（7.2%）、无名念珠菌4例（4.1%）、其他念珠菌6例（6.2%）。念珠菌培养阳性后30 d内死亡37例,30 d病死率为38.1%。Logistic多因素回归分析显示：年龄（OR=1.104,95%CI：1.041~1.170,P=0.001）、血液系统肿瘤（OR=63.256,95%CI：2.898~1380.833,P=0.008）、APACHEⅡ评分（OR=1.176,95%CI：1.053~1.313,P=0.004）、感染性休克（OR=12.032,95%CI：2.389~60.587,P=0.003）及合并细菌性血流感染（OR=26.016,95%CI：4.002~169.127,P=0.001）是其死亡的独立危险因素;而拔除或更换深静脉置管（OR=0.118,95%CI：0.025~0.559,P=0.007）是念珠菌血症死亡的独立保护性因素。结论念珠菌血症患者分布科室范围广、基础疾病重、侵入性操作多。年龄、高APACHEⅡ评分、感染性休克及合并细菌血流感染是影响念珠菌血症死亡的独立危险因素,拔除或更换深静脉置管是念珠菌血症死亡的独立保护性因素。     

Corynebacterium uberis sp. nov. frequently isolated from bovine mastitis

Several strains belonging to the genus Corynebacterium, but not to any described species of the genus were isolated from bovine mastitic milk samples over the past five years in the diagnostic unit of the University of Bern. Six of these strains (18M0132^T, 17M2518, 18M0913, 19M0083, 20M1046 and 20M1090) that were phenotypically similar were further characterized genotypically. Gram-positive coryneform rods were catalase positive, facultative anaerobe and CAMP-test negative. Whole genome sequencing and subsequent phylogenetic analysis revealed their genome size to be 2.53 Mb and their G + C content to be between 65.4 and 65.5 mol%. Digital DNA-DNA hybridisation (dDDH) showed the highest similarity of only less than 20% with Corynebacterium mastitidis and Corynebacterium frankenforstense, which indicated that the isolates belong to an undescribed Corynebacterium species. This was confirmed by studying the average nucleotide identity (ANI) where the accepted species boundary is around 95% and which ranged between 70.3% and 74.9% with the most closely related species C. mastitidis. We established MALDI-TOF fingerprints of the species, which allows a clear separation from related species and can be used by other laboratories for diagnostic purposes.Based on our analyses we conclude that the selected strains belong to a previously undescribed species and propose the name Corynebacterium uberis sp. nov. The proposed type strain is 18M0132^T (=DSM 111922^T, = CCOS 1972^T).     

Failure costs associated with mastitis in smallholder dairy farms keeping Holstein Friesian × Zebu crossbreed cows

Mastitis is a costly disease and in many areas of the world, these costs have been quantified to support farmers in their decision making with regard to prevention of mastitis. Although for subsaharan circumstances estimates have been made for the costs of subclinical mastitis (SCM), farm-specific cost estimations comprising both clinical mastitis (CM) and SCM are lacking. In this paper, we quantified failure costs of both CM and SCM on 150 Ethiopian market-oriented dairy farms keeping Holstein Friesian × Zebu breed cows. Data about CM were collected by face-to-face interviews and the prevalence of SCM was estimated for each farm using the California mastitis test. All other relevant information needed to calculate the failure costs, such as the consequences of mastitis and price levels, was collected during the farm visits, except for the parameter for milk production losses due to SCM, which was based on literature estimates and subjected to sensitivity analyses. The average total failure costs of mastitis was estimated to be 4 765 Ethiopian Birr (ETB) (1 ETB = 0.0449 USD) per farm per year of which SCM contributed 54% of the costs. The average total failure costs per lactating cow per farm per year were 1 961 ETB, with a large variation between farms (range 0 to 35 084 ETB). This large variation in failure costs between farms was mainly driven by variation in incidence of CM and prevalence of SCM. Milk production losses made the largest contribution (80%), whereas culling contributed 13% to 17% to the total failure costs. In our estimates, costs of veterinary services, drugs, discarded milk and labour made a minor contribution to the total failure costs of mastitis. Relative to the income of dairy farmers in North Western Ethiopia; the total failure costs of mastitis are high. In general, Ethiopian farmers are aware of the negative consequences of CM, but creating awareness of the high costs of SCM and showing large variation between farmers may be instrumental in motivating farmers to also take preventive measures for SCM.     

New approaches for risk assessment and management of bovine protothecosis

Protothecosis is a potential zoonosis related to bovine mastitis. In several countries, a higher incidence of protothecal bovine mastitis that is being recorded and the resistance of Prototheca species to various factors (chlorine, high temperatures, antimicrobial and antiseptic treatments, pH variations), make it difficult to control its spread among farms. The authors aim to describe the infection caused by microalgae, focusing on the problems within cattle farms and proposing new approaches to farm management, based on Regulation (EU) No 2016/429 on transmissible animal diseases. This new flexible approach, based on risk analysis, is a further tool in protecting against Prototheca species. The list of transmissible animal diseases under Regulation (EU) No 2016/429 includes those caused by microorganisms resistant to antimicrobials, which can have important implications for human and animal health, feed and food safety. This approach would involve a series of changes to the rules used for Official Controls (Regulation (EU) No 2017/625) moving from the concept of the food chain to that of the agri-food chain.     

Incidence of Subclinical Mastitis and Prevalence of Major Mastitis Pathogens in Organized Farms and Unorganized Sectors

Subclinical mastitis (SCM) represents a major proportion of the burden of mastitis. Determining somatic cell count (SCC) and electrical conductivity (EC) of milk are useful approaches to detect SCM. In order to correlate grades of SCM with the load of five major mastitis pathogens, 246 milk samples from a handful of organized and unorganized sectors were screened. SCC (>5 × 10⁵/mL) and EC (>6.5 mS/cm) identified 110 (45 %) and 153 (62 %) samples, respectively, to be from SCM cases. Randomly selected SCM-negative samples as well as 186 samples positive by either SCC or EC were then evaluated for isolation of five major mastitis-associated bacteria. Of the 323 isolates obtained, 95 each were S. aureus and coagulase-negative staphylococci (CoNS), 48 were E. coli and 85 were streptococci. There was no association between the distribution of organisms and (a) the different groups of SCC, or (b) organised farms and unorganised sectors. By contrast, there was a significant difference in the distribution of CoNS, and not other species, between organized farms and unorganized sectors. In summary, bacteria were isolated irrespective of the density of somatic cells or the type of farm setting, and the frequency of isolation of CoNS was higher with organized farms. These results suggest the requirement for fine tuning SCC and EC limits and the higher probability for CoNS to be associated with SCM in organized diary sectors, and have implications for the identification, management and control of mastitis in India.     

Impact of subclinical and clinical mastitis on sensitivity to pain of dairy cows

A total of 90 cows from three commercial farms were used to evaluate the relationship between subclinical mastitis and clinical mastitis and thermal nociceptive threshold. Milk strips from all udder quarters were tested for clinical mastitis with visual inspection of milk and udder alterations and for subclinical mastitis using California Mastitis Test. Milk yield was recorded, milk was sampled and further analyzed for somatic cells count (SCC). Cows were considered healthy when SCC<200 000 cells/ml and no visual alterations in milk and/or udder, with mild subclinical mastitis when SCC>200 000 cells/ml and no visual alterations in milk and/or udder, with moderate subclinical mastitis when SCC>500 000 cells/ml and no visual alterations in milk and/or udder and with clinical mastitis when visual alterations in milk and/or udder were detected. Nociceptive threshold was evaluated with the thermal threshold meter apparatus applied to the rear legs. Thermal threshold (TT) decreased when we compared healthy cows with cows presenting clinical mastitis and tended to decrease when we compare healthy cows with those with moderate subclinical mastitis. TT was lower at the ipsilateral rear leg compared with the contralateral leg to the infected mammary gland. TT linearly decreases as _log10SCC increased and it showed sharp decrease as _log10SCC exceed the value of 6.4. Increase in one unit of _log10SCC increased the odds of low thermal threshold (lower than 55.8°C). Subclinical mastitis might be a welfare issue as it tended to decrease nociceptive thermal threshold.     

A study on associaton between mastitis and serologically defined class I bovine lymphocyte antigens (BOLA-A) in Norwegian cows

A total of 102 cows was tested for class I antigens of the bovine major histocompatibility complex. Half of the animals (51) had completed at least four lactations without any veterinary treatment for mastitis. The distribution of BoLA-A antigens among these relative mastitis-resistant cows was compared to that in the other half of the material (51), which comprised animals with at least one recorded treatment for mastitis. There were no statistically significant differences in BoLA-A antigen frequency between cows with mastitis and cows without mastitis. The two most common antigens were A2 and w16. The frequency of these two antigens deviated from earlier estimates within the Norwegian cattle (NRF) population, the difference for w16 being statistically significant.     

Longitudinal random effects models for genetic analysis of binary data with application to mastitis in dairy cattle

A Bayesian analysis of longitudinal mastitis records obtained in the course of lactation was undertaken. Data were 3341 test-day binary records from 329 first lactation Holstein cows scored for mastitis at 14 and 30 days of lactation and every 30 days thereafter. First, the conditional probability of a sequence for a given cow was the product of the probabilities at each test-day. The probability of infection at time t for a cow was a normal integral, with its argument being a function of "fixed" and "random" effects and of time. Models for the latent normal variable included effects of: (1) year-month of test + a five-parameter linear regression function ("fixed", within age-season of calving) + genetic value of the cow + environmental effect peculiar to all records of the same cow + residual. (2) As in (1), but with five parameter random genetic regressions for each cow. (3) A hierarchical structure, where each of three parameters of the regression function for each cow followed a mixed effects linear model. Model 1 posterior mean of heritability was 0.05. Model 2 heritabilities were: 0.27, 0.05, 0.03 and 0.07 at days 14, 60, 120 and 305, respectively. Model 3 heritabilities were 0.57, 0.16, 0.06 and 0.18 at days 14, 60, 120 and 305, respectively. Bayes factors were: 0.011 (Model 1/Model 2), 0.017 (Model 1/Model 3) and 1.535 (Model 2/Model 3). The probability of mastitis for an "average" cow, using Model 2, was: 0.06, 0.05, 0.06 and 0.07 at days 14, 60, 120 and 305, respectively. Relaxing the conditional independence assumption via an autoregressive process (Model 2) improved the results slightly.     

Effects of an immunomodulatory feed additive on the development of mastitis in a mouse infection model using four bovine-origin isolates

The goal of this study was to examine the ability of a commercially available feed additive (OmniGen-AF) to reduce mammary infections caused by a single strain of mastitic pathogens (Streptococcus uberis, Escherichia coli, Staphylococcus aureus and Klebsiella pneumoniae) and to examine the effects of the additive on markers of mammary immunity. Four experiments were completed using a murine model of bovine mastitis. Infection progression was examined using Sybr-green- and TaqMan-based quantitative PCR assays of 16S ribosomal DNA. Infection of the mammary gland with all pathogens caused rapid (24 to 48 h) appearance of pathogen DNA in mammary tissue. Provision of the feed additive for 2 weeks before infection significantly (P < 0.05) reduced the extent of pathogen DNA accumulation in models of S. uberis, E. coli and S. aureus infection. The additive was ineffective in reducing mammary infections caused by K. pneumoniae. We examined mechanisms of action of the additive through assessment of mammary concentrations of mammary myeloperoxidase (MPO), major histocompatibility complex 2 class II (MHC) and macrophage inflammatory protein-1α (MIP) messenger RNA (mRNA) concentrations and by examining serum complement C3 concentration. Infection of the mammary gland increased concentrations of MPO and MHC mRNAs (P < 0.05). Ability of the pathogen to elicit changes in mammary MPO and MHC gene expression was enhanced by the provision of the additive for 2 weeks before infection. These data imply that the additive increased the mammary inflammatory response and increased antigen presentation during a mammary infection. Value of the additive in preventing mastitis in cattle awaits additional studies using a bovine model and further evaluation of additional strains of the pathogens used in this study.     

Isolation and characterization of two anti-staphylococcal bacteriophages specific for pathogenic Staphylococcus aureus associated with bovine infections

AIMS: The aim of this study was to isolate and characterize bacteriophages against bovine Staphylococcus aureus associated with mastitis. METHODS AND RESULTS: We describe the isolation of two anti-staphylococcal phages namely DW2 and CS1 from farmyard slurry. Both phages were characterized by electron microscopy and restriction analysis and shown to belong to the Siphoviridae family. CS1 and DW2 were lytic for representatives of all three clonal groups of Irish mastitis-associated staphylococci. These phages were compared with the previously characterized Myoviridae phage K. Infusion of a cocktail of all three phages at 10(8) PFU ml(-1) into live cow teats resulted in no detectable increase in somatic cell counts in milks indicating that the phages did not irritate the animal. CONCLUSION: Two new anti-staphylococcal phages CS1 and DW2 were isolated and characterized and tested for immunogenicity in animal teats. SIGNIFICANCE AND IMPACT OF THE STUDY: The phages isolated in this study are active against pathogenic S. aureus and may be incorporated into teat-dips or teat-washes as a non-antibiotic prophylaxis against staphylococcal bovine mastitis.