排序方式: 共有70条查询结果,搜索用时 15 毫秒
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奶牛乳腺炎调查及病因分析 总被引:1,自引:0,他引:1
对佳木斯市4所奶牛场进行流行病学调查,研究临床型乳腺炎和隐性乳腺炎的发病率以及病因。对4所奶牛场的390头泌乳牛进行检测,其中218头患有隐性型乳腺炎,头发病率为55.90%;17头患有临床型乳腺炎,头发病率为4.43%;乳腺炎的头发病率为60.26%。在被检的1416个有效乳区中,患有隐性型乳腺炎的乳区有792个,乳区阳性率为55.93%;患有临床型乳腺炎的乳区有20个,乳区阳性率为1.41%。对牛场圈舍条件和生产、管理诸环节调查分析表明,引起奶牛乳腺炎的主要原因为饲养管理水平较低、饲料品质较低、挤奶工不能严格遵守无菌操作、高产奶牛乳头未开展干奶期预防工作等。 相似文献
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Zheng Zhang Yong‐xiang Yu Yong Jiang Yin‐geng Wang Mei‐jie Liao Xiao‐jun Rong Kai Wang Hao Zhang Jing Chen 《Journal of fish diseases》2019,42(5):623-630
Vibrio rotiferianus is an important marine pathogen of various aquatic organisms and can be found widely distributed in the marine environment. To further characterize this pathogen, the pathogenic properties and genome of V. rotiferianus SSVR1601 isolated from Sebastes schlegelii with skin ulcer were analysed. SSVR1601 was shown to be short rod‐shaped cell with a single polar flagellum. Different degrees of pathological changes in fish kidney, intestine, gills and liver were observed after SSVR1601 challenge. The SSVR1601 genome consists of two chromosomes and two plasmids with a total of 5,717,113 bp, 42.04%–44.93% GC content, 5,269 predicted CDSs, 134 tRNAs and 40 rRNAs. The common virulence factors including OMPs, haemolysin, flagellin, DNase, entF, algU, tcpI, acfB and rfaD were found in strain SSVR1601. Furthermore, factors responsible for iron uptake (fur, fepC and ccmC) and types II, IV and VI secretion systems were detected, which are likely responsible for the pathogenicity of SSVR1601. The antimicrobial resistance genes, bacA, tet34 and norM, were detected based on Antibiotic Resistance Genes Database. The phylogenetic analysis revealed SSVR1601 to be most closely related to V. rotiferianus strains CAIM577 and B64D1. 相似文献
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贩运仔猪腹泻综合症是近年养猪生产中出现的一种新疾病.主要临床特征是:仔猪瘦弱;大量腹泻.腹泻率最低为30%,最高达100%,平均为59.6%;生长停滞;严重的出现死亡,死亡率为12%.用“护仔康”预防该病,腹泻可减少91%,日增重较对照组提高82.7%,料肉比降低35.4%,增重成本减少13.6%. 相似文献
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一起猪无名高热综合征病例的病原分离鉴定 总被引:1,自引:0,他引:1
某猪场发生以体温升高为特征的病例。笔者对其送检的内脏样本进行了病原学检测和病原的分离与鉴定,结果从其内脏样本中检测和分离到多种病原。从其内脏组织中分离到2株细菌,通过细菌学方法鉴定,一株为副猪嗜血杆菌,另一株为猪链球菌;将送检样本接种到Marc 145细胞,能观察到细胞病变,收获的病毒液经PCR检测,为蓝耳病病毒阳性;将送检的样本接种SPF鸡胚,收获的鸡胚尿囊液有血凝性,血凝试验(HA)和血凝抑制试验(HI)鉴定为猪副黏病毒。 相似文献
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为确定河南地区杨树黄叶病的病因并提出有效的防治措施,开展了元素补充、组织粉碎回接、微生物分离回接、线虫检测、电子显微镜切片观察、植原体的PCR及DAPI检测等实验。结果表明:对轻度病株施硫酸亚铁有较好的治疗效果;回接组织粉碎物的健株无症状表现;从病株的根、茎、叶中分离了4种微生物并进行了回接,27.5%的接种苗出现了与黄叶病相似的症状;在病株体内没有发现植原体和内寄生性线虫;电子显微镜下观测到了杆状细菌存在。研究结果对该病害的后续研究具有重要的参考价值。 相似文献