贵阳市奶牛隐性乳房炎发病情况调查

采用加州乳房炎检测法(CMT)对贵阳市清镇、乌当区、花溪区和开阳县的4个规模化奶牛场奶牛隐性乳房炎的发病情况进行了调查,共检测了284头泌乳奶牛的1 136个乳区.结果表明,奶牛隐性乳房炎的头发病率和乳区发病率分别为53.8％、26.1％.数据表明,奶牛隐性乳房炎与胎次、年龄有很大关系.不同胎次和年龄的泌乳奶牛隐性乳房炎阳性率差异极显著(P＜0.01).结果提示,规模化奶牛养殖场进行常态化的乳房炎检查和实验室检验是非常必要的,可以随时监控隐性乳房炎的发病情况,为促进奶业发展打下坚实基础.     

奶牛隐性乳房炎发病率调查

为了探讨隐性乳房炎的发病规律和降低隐性乳房炎的发病率,对桂南地区3个奶牛养殖场进行了隐性乳房炎调查,结果发现奶牛隐性乳房炎发病率为39.7%,不同奶牛场发病率、不同胎次奶牛及不同季节奶牛隐性乳房炎的发病率差异不显著,而各泌乳期奶牛的隐性乳房炎的发病率差异显著(P0.05)。     

昆明市奶牛隐性乳房炎流行状况调查

奶牛隐性乳房炎发病率高、流行广,是导致奶业经济损失最大的疾病。为了解昆明市奶牛场隐性乳房炎的流行状况,采用加州乳房炎检测法(CMT)对昆明市周边3个标准化奶牛场和3个奶牛合作社奶牛按照30%比例进行随机抽样检查。在抽检的2 297份乳样中,隐性乳房炎阳性数为897份,阳性率为39.05%,规模化奶牛场的隐性乳房炎阳性率(28.79%)显著低于奶牛合作社(56.21%)(P<0.01);奶牛后乳区发病率(69.34%)明显高于前乳区(57.64%);随着产犊胎次的增加,奶牛乳房炎患病率随之显著增高。本调查对掌握昆明地区奶牛隐性乳房炎的发病情况,以及早发现和控制该病发生、提高牛奶质量具有重要的指导意义。     

河南清丰县奶牛隐性乳房炎发病规律研究

为了解河南清丰县奶牛隐性乳房炎发病情况,为今后该地区防控本病提供科学参考,选取该地区3 个规模化养殖场和2 个散养户共320 头泌乳牛,采用美国加利福尼亚快速诊断法(CMT)检测。结果表明,该地区奶牛隐性乳房炎头发病率为46.5%,规模化养殖场和散养户的发病率分别为45.3%(129/285)和57.1%(20/35),差异显著(P ＜0.05)。且发病率随奶牛胎次的增加而升高,5 胎次以上达78.6%;随日产奶量的增加而降低,日产奶量≤15 kg的奶牛发病率为70.1%,＞30 kg的发病率为13.8%,差异极显著(P ＜0.01)。     

贵阳市奶牛隐性乳房炎调查分析

采用CMT诊断法对贵阳市所属清镇市、乌当区、花溪区和开阳县的4个规模化奶牛场进行了奶牛隐性乳房炎的发病率调查，共检测284头，1136个乳区。结果表明：头发病率为53．8％，乳区发病率为26．1％；奶牛隐性乳房炎的阳性率与胎次、年龄有很大关系，不同胎次和年龄的泌乳期奶牛隐性乳房炎阳性率差异极显著（P〈0．01）。     

奶牛隐性乳房炎发病率调查及病原菌的分离鉴定

本试验调查了广东省大型奶牛场隐性乳房炎的发病率情况,并采集相关乳房炎样品进行细菌分离鉴定,确定广东省大型奶牛场奶牛乳房炎的种类. 1材料与方法 1.1奶牛隐性乳房炎发病率的调查方法 1.1.1加州乳房炎检测法(CMT)诊断液的配制诊断液由十二烷基硫酸钠40 g、苛性钠15g和溴钾酚紫0.1g溶于蒸馏水中定容到1 000 mL配制而成.     

河南新乡市奶牛隐性乳房炎发病情况调查与分析

为了解河南省新乡市奶牛隐性乳房炎发病情况,本研究采用CMT方法对1 862头奶牛进行隐性乳房炎诊断,调查不同地区、胎次、季节、年龄和泌乳量与隐性乳房炎发病的规律。结果表明,新乡市奶牛隐性乳房炎发病率平均为45.2%,新乡县发病率最高,为52.6%,获嘉县发病率最低,为34.4%;5胎次以上奶牛隐性乳房炎发病率最高,为72.7%;每天泌乳量在20 kg/d以下的奶牛发病率最高,为69.4%;散养户发病率为62.4%。结果显示,新乡市奶牛隐性乳房炎广泛存在,需要高度重视,应加强防控,提高饲养管理水平。     

青海省海北州奶牛乳房炎发病情况调查

为了解青海省海北州奶牛乳房炎的发病情况,对2016年采自青海省海北州规模化奶牛场、奶牛合作社、散养户的2 029份奶牛样品进行了临床型乳房炎和隐性乳房炎的检测。结果显示,临床型乳房炎发病率为4.29%,隐性乳房炎发病率为13.41%,临床型乳房炎乳头发病率为1.88%,隐性乳房炎乳头发病率为4.84%;临床型乳房炎的发病率以奶牛合作社(机器挤奶)最高,散养户(手工挤奶)次之,规模化奶牛场(机器挤奶)最低,隐性乳房炎的发病率均以奶牛合作社(机器挤奶)最高,规模化奶牛场(机器挤奶)次之,散养户(手工挤奶)最低;1胎、2胎的发病率、瞎乳头率、乳头发病率均较低,5胎、6胎及以上的发病率、瞎乳头率、乳头发病率均明显偏高;2岁、3岁的发病率、瞎乳头率、乳头发病率均较低,6岁、7岁及以上的发病率、瞎乳头率、乳头发病率均明显偏高。结果表明,青海省海北州奶牛群中存在不同程度的临床型乳房炎和隐性乳房炎的发病,且发病率与挤奶操作技术水平、奶牛胎次和奶牛年龄均具有一定的相关性,挤奶操作越严格发病率越低,胎次越高发病率越高,年龄越大发病率越高,此结果可为青海省奶牛乳房炎的综合防控提供依据。     

遂平县奶牛隐性乳房炎发病情况的调查

为了弄清遂平县奶牛隐形乳房炎发病情况,应用LMT法对遂平县4个奶牛场共283头奶牛乳液进行检测。结果显示:4个奶牛场奶牛隐形乳房炎发病率分别为60.46%、65.38%、51.61%和45.22%,平均发病率为56.54%;奶牛隐形乳房炎发病率随着胎次和年龄增加而升高,具有正相关性。结果表明该地区奶牛隐性乳房炎发病情况较为严重,需要引起养殖户的重视。     

遂平县奶牛隐性乳房炎发病情况调查

为了弄清遂平县奶牛隐形乳房炎发病情况,应用LMT法对遂平县4个奶牛场共283头奶牛乳液进行检测。结果显示:4个奶牛场奶牛隐形乳房炎发病率分别为60.46%、65.38%、51.61%和45.22%,平均发病率为56.54%;奶牛隐形乳房炎发病率随着胎次和年龄增加而升高,具有正相关性。结果表明该地区奶牛隐性乳房炎发病情况较为严重,需要引起养殖户的重视。     

河北保定部分奶牛场临床型乳房炎发病情况调查研究

为探索奶牛临床型乳房炎的发病情况与泌乳量、泌乳期、季节之间的联系,以河北保定地区5个奶牛场为例进行调查研究。通过对调查结果的统计分析,结果显示：奶牛乳房炎多发生在泌乳90~150 d,泌乳天数越长发病头数越多;从产奶量来看,泌乳量越高发病牛比例越高;从发病季节来看,奶牛乳房炎在秋季发病率高,春季、夏季和冬季发病率低。     

规模化奶牛场奶牛亚临床型乳房炎流行规律调查

目的 本研究旨在摸清兰考县规模化奶牛场奶牛亚临床乳房炎流行规律,为该病的防控提供参考。方法 采用加州奶牛亚临床乳房炎试验（CMT）方法对3 家规模化奶牛场的547 头泌乳奶牛进行亚临床乳房炎检测,调查该病与奶牛胎次、泌乳期和乳区的关系。结果 奶牛阳性率为20.11%,乳区阳性率为10.88%;1~2、3~4和≥5胎次的奶牛发病率分别为13.37%、20.53%和29.46%;泌乳前期、泌乳中期和泌乳后期发病率分别为15.11%、22.12%和30.89%;乳区阳性率介于8.59%~13.16%。结论 兰考县规模化奶牛场奶牛亚临床型乳房炎的发病率相对较低,与胎次、泌乳期存在正相关,与乳区无明显关系。     

辽宁地区奶牛乳房炎源大肠杆菌毒力基因及耐药基因检测分析

为了掌握辽宁地区规模奶牛场乳房炎源大肠杆菌携带的毒力基因和耐药基因,为奶牛养殖业提供更好的乳房炎防制方案,本研究采用PCR检测方法对辽宁地区多个规模奶牛场临床奶牛乳房炎奶样中分离的66株大肠杆菌进行了4种毒力基因和4种耐药基因的检测分析。结果发现,66株大肠杆菌中仅有1株未检出相关目的基因,其余65株中最少检出2种目的基因,最多检出7种目的基因。其中,毒力基因stx2e、eaeA、K99和astA的检出率分别为56.1%、47.0%、34.8%和31.8%,双重毒力基因的检出率达到43.9%,以eaeA/stx2e基因型的检出率最高;耐药基因sul3、sul1、cmlA及aacA4的检出率分别为87.9%、83.3%、40.9%和28.8%,双重耐药基因的检出率为36.4%,以sul1/sul3基因型检出率最高;三重耐药基因的检出率为37.9%,以cmlA/sul1/sul3检出率最高。本研究结果证实,辽宁地区奶牛乳房炎源大肠杆菌携带磺胺类耐药基因和氯霉素类耐药基因的比率较高,与大肠杆菌的耐药性有较直接的关系,该结果对于辽宁地区奶牛乳房炎的防制具有重要的指导意义,更具有重要的公共卫生意义。     

Detection and Analysis of Virulence Genes and Drug Resistance Genes in E. coli Strains Isolated from Dairy Cows with Clinical Mastitis in Liaoning Region

In order to understand the virulence genes and drug resistance genes carried by E.coli strains from dairy cows with mastitis in large-scale dairy farms in Liaoning region, and also provide improved programs for control and treatment of mastitis to dairy farmers, 66 strains of E.coli isolated from milk of dairy cows with clinical mastitis in several large-scale farms in Liaoning region were examined to detect 4 virulence genes and 4 drug resistance genes using PCR methods. The results showed that none of the target genes was detected in only one strain, while at least 2 and up to 7 target genes were detected in the rest of 65 strains. The detection rates of the virulence genes stx2e, eaeA, K99 and astA were 56.1%, 47.0%, 34.8% and 31.8%, respectively. In addition, the detection rate of dual virulence gene reached 43.9%, in which the genotype with the highest detection rate was eaeA/stx2e. The detection rates of the drug resistance genes sul3, sul1, cmlA and aacA4 were 87.9%, 83.3%, 40.9% and 28.8%, respectively. And the dual resistance gene detection rate was 36.4%, in which the highest detection rate was sul1/sul3 genotype; Triple drug resistance gene detection rate was 37.9%, and cmlA/sul1/sul3 presented the highest detection rate. These results confirmed that the E.coli isolated from dairy cow mastitis in large-scale dairy farms in Liaoning region had high detecting rates of sulfonamide resistance genes and chloramphenicol resistance genes, which was directly related to the drug resistance of the E.coli. These results provided important guiding significance for the prevention and control of dairy cow mastitis in Liaoning region as well as the safety of public health.     

石河子地区隐性乳房炎奶牛源大肠杆菌的分离鉴定及耐药性分析

为了解引起石河子地区规模化奶牛场隐性乳房炎奶牛源大肠杆菌的流行情况及其耐药性,本试验采用兰州乳房炎检测板(Lanzhou mastitis test,LMT)对石河子地区11个规模化奶牛场进行了检测,同时对无菌采集的检测为阳性的乳样进行了大肠杆菌分离鉴定及耐药性分析.结果显示,石河子地区11个规模化奶牛场的隐性乳房炎感染阳性率为44.56%(313/1950);对313份无菌采集的乳样进行细菌分离鉴定,结果共分离出病原菌108株,其中大肠杆分离率为14.81%(16/108);药敏试验结果显示16株大肠杆菌对氧氟沙星、头孢唑啉、克林霉素高度敏感,对庆大霉素、氨苄西林、链霉素中度敏感,对阿莫西林、四环素有耐药性.本试验为该地区大肠杆菌源性隐性乳房炎的防制提供科学依据.     

新疆石河子奶牛隐性乳房炎源金黄色葡萄球菌的分离鉴定及药物敏感性分析

为了解石河子地区部分规模化奶牛场奶牛隐性乳房炎源金黄色葡萄球菌的生物学特性及药物敏感性,为科学防治该病的发生提供参考依据,本试验选择了石河子周边地区不同规模的11个奶牛场,通过采用LMT法检测其隐性乳房炎的感染率,并从采集到的313份隐性乳房炎奶样中分离鉴定金黄色葡萄球菌,同时采用纸片扩散法（K－B法）对分离株的药物敏感性进行了分析。结果表明,试验区奶牛隐性乳房炎的总阳性率为44．56％（869／1950）,金黄色葡萄球菌的分离率为44．71％（93／208）;药敏试验结果表明,大部分菌株对阿莫西林、红霉素、四环素表现为高度耐药,耐药率分别为92．30％（24／26）、80．77％（21／26）、80．77％（21／26）;对庆大霉素、氧氟沙星、头孢唑啉表现为敏感,敏感率分别为57．70％（15／26）、76．92％（20／26）、76．92％（20／26）;部分菌株对克林霉素中度敏感,敏感率为46．15％（12／26）。建议在选用抗生素治疗奶牛隐性乳房炎时,以流行菌株的药物敏感性为依据。     

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。     

The incidence and aetiology of clinical bovine mastitis on 14 farms in Northland,New Zealand

AIM: To estimate the incidence of clinical mastitis and the frequency of isolation of mastitis-causing organisms from clinical cases in one lactation season (July 2005 to May 2006) on 14 dairy farms from the Northland region of New Zealand.

METHODS: Cases of clinical mastitis were determined by trained farm personnel who recorded the identity of affected cows. Pooled milk samples from affected quarter(s) were aseptically collected by the farm personnel, for microbiology. Mean numbers of affected cows and quarters were compared at the population and farm level per 305 cow-days-at-risk (DAR).

RESULTS: One or more cases of clinical mastitis occurred in 559/3,765 (14.8%) lactating cows. The average incidence of clinical mastitis was 0.19 cases per 305 DAR. The incidence in rear quarters (56.2%) was 1.3 times (p=0.027) that of front quarters (43.8%). The incidence of clinical mastitis and numbers of affected quarters were signifi cantly infl uenced by the stage of lactation (higher in early lactation), age (higher in older cows) and farm. At the cow level, the most common isolates were Staphylococcus aureus (23.7%) and Streptococcus uberis (23.3%). No causative organisms were identifi ed in 19.9% of the samples. Each cow had an average of 1.8 quarters affected during a case of clinical mastitis.

CONCLUSIONS: This study demonstrated a higher incidence of staphylococcal clinical mastitis on dairy farms from Northland than has been reported in other regions of New Zealand.     

Prevalence of subclinical mastitis in dairy farms in urban and peri-urban areas of Kampala, Uganda

It is widely recognized that subclinical mastitis (SCM) is an extensive problem in the dairy industry worldwide. It is of particular concern in developing countries. The aim of this study was to establish the prevalence of SCM in dairy cattle in the urban and peri-urban areas of Kampala, Uganda and to gain information about pathogens and antibiotic resistance patterns. The study was conducted as a field study in 18 smallholder dairy farms in peri-urban Kampala, Uganda. All cows at the farms were physically examined, and cows with signs of clinical mastitis were excluded. Cows (n?=?195) were tested with California Mastitis Test (CMT), and udder quarters with CMT score ≥3 (scale 1–5) were milk sampled for bacteriological analysis. To allow further sub-analysis of the results, the stage of lactation, parity, milk production, production type, udder hygiene, and cow breed were recorded. Results indicate that 86.2 % (n?=?168) of the tested cows had SCM in one or more quarters. The most common bacteriological outcome was infection with coagulase-negative staphylococci (54.7 %), followed by negative growth (24.9 %) and streptococci (16.2 %); all of which (n?=?34) were sensitive to penicillin. Of the tested staphylococci (n?=?17), the majority (58.9 %) were positive for penicillinase production. Factors with significant impact on the prevalence of SCM at cow level were the stage of lactation, parity, and production type. The results suggest that the prevalence of SCM in Uganda is substantially higher than reported in previous studies and in other comparable developing countries. This implies that SCM deserves more attention and that improvement in dairy cow husbandry in terms of hygiene and management is necessary.     

Milk yield and associated economic losses in quarters with subclinical mastitis due to <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> in Ethiopian crossbred dairy cows

The objective of the study was to estimate the prevalence and losses associated with subclinical mastitis (SCM) caused by Staphylococcus aureus in Ethiopian crossbred dairy cows. A split-udder trial was carried out to determine milk yield losses in udder quarter with S. aureus-caused SCM. Each quarter of the study cows was examined using the California Mastitis Test (CMT) and quarter milk production was measured over a period of 8 days. Milk yield losses for CMT positive quarters were estimated by comparing production of quarters with CMT score 0. Mean milk yield for uninfected healthy quarters was 1.66 kg per milking (95% CI, 1.66–1.55 kg per milking), and the rate of milk reduction for quarters with CMT scores of 1+, 2+, and 3+ was 25%, 33%, and 48%, respectively. Economic losses at different farm-size levels were calculated by multiplying the prevalence of CMT scores with milk yield losses associated with respective CMT scores. In Debre Ziet dairy herds, a quarter with SCM due to S. aureus lost an average of 34.5% of its potential milk production while the total milk yield loss per cow was estimated at 6.8%. Losses were highest in large-scale (13%) farms and lowest (3.7%) in small-scale. Based on the prevalence, the overall financial loss for each cow per lactation was 984.64 Eth Birr (US78.65) and losses in large farms (1,882.40 Eth Birr or US78.65) and losses in large farms (1,882.40 Eth Birr or US150.35) were over 3.5 times the loss in small-size farms. These figures possibly underestimate the potential benefits of mastitis control program as they do not include other direct and indirect costs.