奶牛乳房炎的病原菌分离鉴定与药物敏感性试验

对山东济南市5个奶牛场的165份临床型和147份隐性乳房炎奶样进行了分离鉴定.临床型未用利福平复合新药奶样48份,细菌检出率为83.33%;用该药2 d内采集的奶样117份,细菌检出率60.68%.隐性乳房炎奶样细菌检出率68.03%.用利福平复合新药对未用该药奶样分离菌35株和用该药后有代表性的分离菌40株,共75株临床型分离菌进行药敏试验,结果84%为高度敏感(63/75),16%为中度敏感(12/75).鉴定的细菌有葡萄球菌,链球菌,大肠杆菌,棒状杆菌,芽孢杆菌等.根据用药后患病奶牛的临床表现和奶样细菌分离情况,表明该药对奶牛乳房炎具有显著疗效.     

宁夏地区奶牛乳房炎源阴道加德纳菌分离鉴定及耐药性分析

为了研究奶牛乳房炎源阴道加德纳菌(GV)的耐药情况,从宁夏部分奶牛场采集临床型乳房炎奶牛乳样94份、隐性乳房炎奶牛乳样70份进行细菌分离鉴定,得到2株GV(均来自于临床型乳房炎奶牛乳样);动物试验结果表明GV对奶牛乳房炎没有致病性;药敏试验结果表明分离菌对哌拉西林、万古霉素、四环素、克林霉素耐药,对阿莫西林中介,对其他药物均敏感。     

石河子地区奶牛乳房炎大肠埃希菌的分离鉴定及耐药性分析

为了解引起新疆石河子地区规模化牛场奶牛乳房炎大肠埃希菌的流行情况及其耐药性,对石河子地区部分奶牛场采集85份临床型或隐性乳房炎奶样进行大肠埃希菌的分离、鉴定及耐药性试验。结果表明,从85份奶样中分离到127株细菌,其中大肠埃希菌27株,占21.26%。耐药性试验结果显示,27株大肠埃希菌全部对杆菌肽耐药,66%以上对青霉素、复方新诺明、红霉素耐药,80%以上对丁胺卡那霉素、恩诺沙星、氟苯尼考、头孢曲松、头孢哌酮5种药物敏感。调查结果为本地区奶牛乳房炎的防控提供了参考依据。     

奶牛隐性乳腺炎病原菌的分离鉴定

用兰州乳房炎试验(LMT)对来自西安市某个牛场的76份奶样作隐性乳房炎检验，并对乳样进行细菌分离鉴定。结果表明，该牛场的隐性乳房炎检出率为33％，阳性乳样中细菌检出率为93．4％。阴性乳样中病原菌检出率为28％，在检出的94株细菌中，共有5种菌22株是与乳房炎有关的病原菌。其中葡萄球菌和链球菌占病原菌总数的90％以上。是引起该场奶牛隐性乳房炎的主要病原菌。     

奶牛场隐性乳房炎病原学研究

用加州乳房炎实验(CMT)检测烟台市某场牛群隐性乳房炎69头,137个乳区的奶样,细菌分离结果表明,头细菌检出率为75%;乳区细菌检出率为69%,从其中分离鉴定出链球菌11株,金黄色葡萄球菌5株、溶血性表皮葡萄球菌6株。另外还有大量的非溶血性表皮葡萄球菌和环境性致病菌如蜡样芽胞杆菌等,其中链球菌和葡萄球菌是引起该场隐性乳房炎的主要病原菌。     

新疆铁门关地区奶牛乳房炎病原菌分离鉴定及主要病原菌药敏试验

本试验从新疆铁门关地区采集166份乳房炎患牛的奶样,进行了细菌分离鉴定并对主要病原菌进行药敏试验。结果表明,从奶样中共分离出12种267株细菌,其中主要病原菌为:金黄色葡萄球菌86株,检出率33.6%;大肠杆菌68株,检出率25.5%;停乳链球菌33株,检出率12.4%;无乳链球菌25株,检出率9.4%。临床型乳房炎大部分为混合感染(混合感染的感染率为61.4%),隐性乳房炎大部分为单独感染(单独感染的感染率为88.5%)。选择16种抗生素采用K-B纸片法对分离出的病原菌进行药敏试验,4种主要病原菌对头孢曲松钠、头孢哌酮、克林霉素、氟苯尼考敏感。该试验为本地区奶牛乳房炎的防治提供了理论依据。     

山东潍坊市部分奶牛场奶牛乳房炎病原菌的分离鉴定及耐药性检测

为了解潍坊市当前奶牛乳房炎的发病以及病原菌的种类和耐药性情况,为该地区奶牛乳房炎的防治提供参考,采集潍坊市6个奶牛场临床型和隐性型乳房炎奶样各100份,进行了细菌分离和鉴定。结果细菌检出率为91.50%（183/200）,细菌混合感染奶样占检出细菌奶样的84.70%（155/183）;共分离到265株细菌,其中链球菌（无乳链球菌、停乳链球菌、乳房链球菌）占38.11%,金黄色葡萄球菌占34.34%,大肠杆菌占16.98%,这些是引起奶牛乳房炎的主要病原菌。将这些病原菌进行药物敏感试验,结果显示,敏感率高的药物依次是头孢喹肟（80.59%）、恩诺沙星（68.35%）、头孢噻呋（68.35%）和氟苯尼考（67.51%）,耐药率高的药物依次是青霉素（37.97%）、链霉素（26.16%）和四环素（10.55%）。     

河南省42株奶牛临床型乳房炎病原菌的分子鉴定及药敏试验

为了解近年来河南省奶牛临床型乳房炎的主要病原菌种类及药物敏感性,从郑州、焦作等地奶牛场采集乳房炎奶样47份,采用微生物学方法、16S rRNA基因PCR扩增、序列分析比较等方法对分离菌株进行鉴定,并用K-B纸片法对分离菌株中的26株致病菌进行药物敏感性试验。结果显示,47份奶样中共分离出17种42株细菌,环境性病原菌32株,主要包括大肠杆菌、克雷伯氏菌、芽孢杆菌、葡萄球菌等,检出率17.6%~20.6%。郑州2家奶牛场分离出的23株致病菌对16种药物均有不同程度的耐药,耐药率4.35%~56.52%。焦作1家奶牛场分离出的3株病原菌只对复方新诺明、氨苄西林、四环素、氯霉素耐药。部分菌株多重耐药严重,同时对3~11种药物耐药。结果说明分离的奶牛临床型乳房炎的病原菌种类很多,并且已经产生了严重的耐药性。     

奶牛乳汁中细菌的分离鉴定与药物敏感性试验

对南京市某奶牛场19头奶牛抽取乳汁进行细菌分离鉴定。其中,健康奶牛9头,患显性乳房炎奶牛6头,患隐性乳房炎奶牛4头。共分离鉴定出蜡状芽胞杆菌1株、克雷伯菌属细菌1株、肠杆菌属细菌2株、葡萄球菌属细菌12株。对分离出的16株细菌采用药敏纸片法进行常用抗生素的药物敏感性试验。结果表明,分离菌中的蜡状芽孢杆菌对庆大霉素、氯霉素、复方新诺明、呋喃妥因、链霉素和红霉素均较为敏感,克雷伯菌仅对氯霉素较敏感,肠杆菌仅对庆大霉素敏感,葡萄球菌则对青霉素、氯霉素、红霉素较为敏感。     

宁夏地区奶牛隐性乳房炎主要病原菌分离鉴定及药敏试验

[目的 ]了解宁夏地区奶牛隐性乳房炎主要病原菌流行情况及主要病原菌的耐药特征。[方法 ]采集宁夏地区5个规模化奶牛养殖场乳样共计461份,分离培养后,应用全自动细菌鉴定仪进行鉴定并选择主要致病菌进行药敏试验。[结果 ]隐性乳房炎阳性检出率平均为65.3%(301/461);分离到金黄色葡萄球菌22株、无乳链球菌5株、大肠杆菌10株。这些细菌对阿米卡星、头孢噻肟等药物敏感,对青霉素与环丙沙星耐药。[结论 ]宁夏地区奶牛隐性乳房炎的阳性率较高,主要病原菌对阿米卡星、头孢噻肟等药物敏感。     

Isolation and Identification of Pathogenic Bacteria Causing Bovine Subclinical Mastitis in Eastern Hebei Province

In this study, the milk samples of 1 021 cows in eight dairy farms in Eastern Hebei Province were collected and detected with LMT reagent and somatic cell count for subclinical mastitis. Pathogenic bacteria in subclinical mastitis positive milk samples were isolated and identified.The results showed that 60.63%(619/1 021) of the sampled cows were diagnosed with subclinical mastitis, and mixed infections accounted for 88.21%(546/619) of the cases. In addition, 82 strains of 14 species were isolated from the subclinical mastitis positive milk samples, including 36 strains of Staphylococcus(43.90%), 33 strains of Streptococcus(40.24%), 8 strains of Enterobacteriaceae(9.76%) and 5 strains of Corynebacterium(6.10%), respectively. The results proved that Staphylococcus aureus and Streptococcus agalactiae are the main pathogenic bacteria causing bovine subclinical mastitis in Eastern Hebei Province.     

Prevalence of coagulase-negative staphylococci in bovine mastitis in Zimbabwe

This study was carried out to determine the prevalence of coagulase-negative staphylococci in clinical and subclinical mastitis in commercial and small-scale farms in Zimbabwe. Thirty five quarter milk samples from clinical mastitis cases and 371 quarter milk samples from cows with subclinical mastitis were cultured for bacterial pathogens. The most frequent pathogens isolated in clinical mastitis were the enteric bacteria (31.4%), followed by coagulase negative staphylococci (22.9%) and then Staphylococcus aureus (17.1%), whereas in subclinical mastitis S. aureus (34.2%) and coagulase-negative staphylococci were (33.2%) the most common. Bacillus species were only isolated in milk samples from subclinical mastitis. Coagulase-negative staphylococci were observed in mixed infections with other bacteria in only 2.2 of the 406 milk samples from clinical and subclinical mastitis where they were isolated together with Bacillus species in 6 of the 9 mixed infection cases. About 95% of the milk samples from which 131 coagulase-negative staphylococci were isolated had correspondingly high somatic cell counts. The coagulase-negative staphylococci isolated most frequently were S. chromogenes (7.9%), S. epidermidis (7.4%) and S. hominis (5.9%). They were all associated with high somatic cell counts. All the coagulase-negative staphylococci isolates were susceptible to cloxacillin and erythromycin, and more than 90% of the isolates were susceptible to neomycin, penicillin and streptomycin. The highest resistance was to tetracycline (17.6%), followed by lincomycin (13.7%). About 8% of the isolates were resistant to both penicillin and streptomycin.     

奶牛隐性乳房炎的流行病学调查及病原菌的分离鉴定

对某大型奶牛场进行隐性乳房炎的流行病学调查,以及致病菌的分离鉴定,结果得出:对同一牛舍76头泌乳牛进行CMT检测,其中隐性乳房炎的牛发病率为68.42%(52/76),在278个有效乳区中,隐性乳房炎的乳区有109个,乳区阳性率为39.21%(109/278),从10份被检乳汁中共分离出59株细菌,经生化鉴定其主要致病菌为金黄色葡萄球菌、无乳链球菌和大肠杆菌,分别占总数的18.64%。     

新疆克拉玛依地区奶牛隐性乳房炎病原菌的分离鉴定

用兰州乳房炎检测试剂(Lanzhou mastitis test,LMT)对克拉玛依规模化奶牛场进行了奶牛隐性乳房炎流行病学调查。结果显示,该地区奶牛隐性乳房炎的发病率为70.43%(543/771)。对543份阳性牛乳样品进行了病原菌的分离鉴定,结果发现,阳性乳样品中细菌分离率达89.13%(484/543),葡萄球菌、链球菌、肠杆菌和棒状杆菌为主要致病菌,且多为几种致病菌的混合感染。     

Limulus test--a rapid and simple method for the detection of endotoxins produced by gram-negative bacteria in mastitis milk

According to the present study the limulus amebocyte lysate test (LAL) seems to be a convenient test to detect endotoxin in milk from udder quarters with and without inflammation. The correlation between endotoxin concentration and the results from the bacteriological investigation of 79 milk samples was good (Table I). Determination of endotoxin in 20 milk samples from cases of acute clinical mastitis with high cell count and a negative bacteriological culture showed that all but one had an endotoxin concentration of greater than 1.0 ng/ml milk (Table II). By using a micromethod of the LAL it is possible to detect cases of mastitis caused by gram-negative bacteria about one hour after the sample has reached the laboratory. In a preliminary field study milk from 13 cases of acute clinical mastitis were tested by a modified limulus amebocyte lysate (LAL) test ("cowshed test"). A 100% correlation to bacteriological findings was observed (Table IV). By using the LAL test to detect mastitis cases caused by gram-negative bacteria great economic advantages and less risk for resistance problems can be achieved by using proper antibiotics. This is the fact in Sweden where the frequency of acute clinical mastitis caused by streptococci (100% of strains sensitive for penicillin) and Staphylococcus aureus (about 90% of strains sensitive for penicillin) is high (70-80%) and about 20% are caused by gram-negative bacteria, mostly E. coli.     

冀东地区奶牛隐性乳房炎病原菌的分离鉴定

通过LMT法、乳汁pH检验法和体细胞直接计数等方法相结合,对冀东地区3个大型奶牛场、8个奶牛养殖户选取的1 021头奶牛进行隐性乳房炎流行病学调查与病菌分离鉴定。结果表明,隐性乳房炎发病率为60.63%(619/1021),乳房炎阳性乳样品中细菌分离率达88.21%(546/619)。从543头隐性乳房炎患牛的阳性乳区乳样中分得细菌共4类14种菌82株,其中葡萄球菌36株,占43.90%;链球菌33株,占40.24%;肠杆菌类8株,占9.76%;棒状杆菌5株,占6.10%。冀东地区奶牛隐性乳房炎主要病原菌为金黄色葡萄球菌和无乳链球菌。     

青海省部分规模化奶牛场乳房炎主要病原菌调查分析

为了初步摸清青海省部分规模化奶牛场奶牛乳房炎的发病情况,本研究采集了青海省5个规模化奶牛场共142份样品,进行细菌的分离鉴定、生化实验及耐药性检测。发现在5个规模化奶牛场中都有不同程度的乳房炎发生。鉴定结果显示,在142份样品中共检出大肠杆菌20株,检出率为14.08%(20/142);金黄色葡萄球菌6株,检出率为4.23%(6/142);链球菌2株,检出率为1.41%(2/142)。耐药性检测结果显示,大肠杆菌对氟苯尼考高度敏感,对头孢他啶、丁胺卡那比较敏感,对青霉素、链霉素等其他药物耐药。金黄色葡萄球菌对万古霉素、阿莫西林、氨苄西林、头孢他啶较敏感,对其他药物耐药。链球菌对阿莫西林、氨苄西林敏感,对其他药物耐药。     

关于宁夏地区首次从乳房炎乳样中检出非脱羧勒克菌的研究

从宁夏部分奶牛场(牧场、养殖小区)采集94份临床型乳房炎乳样、70份隐性乳房炎乳样,并分离鉴定出4株非脱羧勒克菌,其中临床型乳房炎分离出1株、隐性乳房炎分离出3株。药敏试验结果表明,4株非脱羧勒克菌均对链霉素、氨基糖苷类、喹诺酮类、头孢类药物敏感;对磺胺类、林可胺类药物则产生不同程度的耐药性。     

Analysis of Clinical Mastitis Pathogenic Bacterial Species in Three Dairy Farms of Different Areas

In order to control mastitis,clinical mastitis pathogenic bacterial species of three dairy farms in different areas were isolated and identified.The types and infection condition of pathogenic bacteria,environmental conditions and management methods of the farms were analyzed.61 clinical mastitis milk samples from three different large-scale dairy farms in Fujian,Xinjiang,and Chongqing were collected for bacterial isolation and identification using traditional microbial identification methods and PCR technology.Among clinical mastitis milk samples collected in this trial,single infection sample was 44 (72.13%)and mixed infections sample was 15 (24.59%).80 bacteria were isolated,mainly E.coli,Staphylococcus and Streptococcus,including 13 strains of infectious microorganisms (16.25%),46 strains of environmental microorganisms (57.50%),11 strains of chance of microorganisms (13.75%),10 strains of other microorganisms (12.50%).Clinical mastitis in three dairy farms were still given priority to single infection,and mixed infection occupies certain proportion,with infectious pathogens and environmental pathogens as the main pathogenic.In the actual production the dairy cow mastitis infection and pathogen species could be carried out through the isolation and identification of mastitis pathogens in large-scale dairy farms.It was helpful to identify the herd management problems and make improvements to better control the occurrence of mastitis combining with the actual production conditions.     

Preliminary studies on the prevalence of Mycoplasma bovis mastitis in dairy in cattle in Australia

A highly sensitive and specific PCR (MB-PCR) was used in preliminary studies to detect M. bovis in milk samples to investigate its association with high somatic cell count (SCC), an indicator of subclinical mastitis and one of the factors in down grading the quality of milk. A total of 186 and 167 herds were tested with 43% and 62% of herds positive for M. bovis in Victoria and North Queensland, respectively. The quarter milks from 52 cows with persistently high SCC were tested by MB-PCR and culture to investigate the association of M. bovis with major mastitis pathogens (MMP). M. Bovis was detected in 77% of cows of which 19% alone had M. bovis without any other bacteria, 17% had M. bovis in combination with major mastitis pathogens and 40% had M. bovis in combination with non-major mastitis pathogens. We believe that M. bovis is widespread in dairy cattle and has the potential to produce disease alone or to predispose the udder to disease caused by major mastitis and environmental pathogens. These studies have revealed a hitherto unrecognised high prevalence of M. bovis in dairy cattle in North Queensland and Victoria in Australia. These initial studies also give a clear association between M. bovis and elevated somatic cell counts.