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1.
胶孢炭疽菌侵染柱花草叶片的显微观察 总被引：1，自引：0，他引：1
为了研究胶孢炭疽菌在柱花草叶片上的侵染进程和植株接种病原菌后的反应,用胶孢炭疽菌孢子悬浮液接种生长6周的热研2号柱花草幼苗,显微观察接种后炭疽菌在柱花草叶片上的侵染过程,统计植株病情指数。结果表明,接种4h时孢子开始萌发、少量形成附着胞;6h孢子大量萌发,12h时大量附着胞形成并形成侵染钉;36h时开始产生菌丝;48h时菌丝大量产生纠结成网状;60h时开始形成分生孢子梗;72h时产生新的分生孢子。接种72h部分病原菌完成了一个侵染循环。同时柱花草发病症状为:叶片24h黄化,有侵染点细胞膜破裂,48h出现褐色病斑,72h病斑出现黑褐色坏死线、点状菌核、绒毛状菌丝,96h细胞崩解死亡,组织液外流。8d病情指数为54.52,11d有55%的接种植株死亡。 相似文献
2.
2011年秋季,浙江省淳安县的桑园大面积发生一种罕见的桑叶特大病斑病害。病叶呈现菌核病的典型症状:叶面形成灰褐色轮纹水渍状病斑,病斑随着病情发展以同心圆状向外延伸,颜色由里到外逐渐变深;叶背的灰色圆形病斑可见多个同心圆形绒毛状菌丝体和分生孢子。病斑与病斑外的部分组织以及病斑同心圆上的绒毛状组织于光学显微镜下可观察到菌丝体与分生孢子形态,病斑边缘组织块在PDA培养基上分离培养的病原菌都可观察到菌丝体形成的菌核。依据以上症状和病原真菌分离培养的形态特征,初步诊断该病为桑叶菌核病,病原为富克尔核盘菌[Sclerotinia fuckeliana(de Bary)Fuck.]。调查16个样点的480株桑树,株发病率为81.25%,叶发病率为37.63%,发病指数18.5。9～10月份气温24.4～18.7℃,多阴雨天,加之连片桑园通风透光能力较弱且相对湿度较大的环境条件,病原菌繁衍迅速,病害呈流行之势。尚未发现有明显抗性的桑树品种。 相似文献
3.
Wales AD Pearson GR Best A Cookson AL La Ragione RM Roe JM Hayes CM Woodward MJ 《Research in veterinary science》2005,78(2):109-115
In a series of experiments involving the inoculation of sheep with Escherichia coli O157:H7, and subsequent detailed histopathological examination of the intestinal mucosa, attaching-effacing (AE) lesions formed by elements of the natural flora were observed in 18% of animals. These incidental AE lesions typically were small and sparse, and were not associated with clinical disease. It was possible to identify further some of the lesional bacteria, revealing that E. coli O115 had formed lesions in one of the seven affected animals, and similarly E. coli O26 had formed some of the lesions in another. As AE strains, source flocks, housing and feed sources were diverse, a common source of lesion-forming bacteria appears to be unlikely. It is postulated that subclinical AE lesions are a mechanism of persistence of AE bacteria in sheep. 相似文献
4.
Propagation of Porcine Cytomegalic Inclusion Disease Virus In Cell Cultures — Preliminary Report 
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下载免费PDF全文 The successful propagation of porcine cytomegalic inclusion disease virus (inclusion-body rhinitis virus) in primary pig lung cell cultures is reported. CID virus was carried through five passages in cell cultures with cytopathic affects appearing from 11 to 18 days post-inoculation. Four pigs inoculated with infected cell culture fluids from the second cell culture passage remained clinically normal. Two, however, had typical inclusion bodies in the glands of the nasal mucosa when examined three weeks post-inoculation. The progressive cytopathic effect produced and the inclusion bodies formed by this strain of porcine CIDV are described. These inclusion bodies appeared to be similar to those formed by cell culture-propagated cytomegaloviruses of man, mouse and guinea pig. 相似文献
5.
家蚕黑尾病主要是由曲霉菌在蚕尾部寄生引起的一种真菌病 ,从病蚕中分离到病原菌有两种 ,一种孢子表面棘多而长、黄褐色 ,孢子大 ,直径 4～ 6 μm ;一种孢子表面棘短而少、蓝绿色 ,孢子小 ,直径 2～ 3μm。黑尾病在高温多湿条件下多发 ,多发生于 4龄中期至 5龄中期。黑尾病病原菌侵染寄生家蚕的过程是 :病原菌分生孢子附着在蚕尾部背板与节间的三角形节间膜处 ,分生孢子发芽侵入蚕体产生黑色小病斑 ,随病情加重病斑加大 ,甚至在病斑处出现节间断裂 ,直至形成黑尾症状。使用药剂防治黑尾病以 5 %亚迪蚕保最佳 相似文献
6.
The impact on database searching arising from inconsistency in the nomenclature of parasitic diseases 总被引：3，自引：0，他引：3
Kassai T 《Veterinary parasitology》2006,138(3-4):358-361
The existing usage of disease names formed from the name of the parasite taxon is characterised by marked heterogeneity. This is largely due to the fact that, for coining disease names, four different suffixes, '-osis', '-iosis', '-asis' and '-iasis', are being used inconsistently. The result is that alternative terms are in use for naming the same disease, e.g. trypanosomosis and trypanosomiasis, fasciolosis and fascioliasis, ascariosis and ascariasis. Inspite of the SNOAPAD/SNOPAD guideline (1988) which proposed the principles of a uniform and standard disease nomenclature, the actual usage depends largely on tradition, educational imprinting and personal preferences, showing great variation. By using alternative disease names as search terms the author investigates in four databases the impact of nomenclatural heterogeneity on information storage and retrieval. It is evident that the existence of alternative disease names in parasitology markedly interferes with the efficacy of online data retrieval. The value of a disease name as a search term was shown to be greatly different in various databases. Until we have to coexist with an inconsistent disease terminology we need to adopt specially structured database-search techniques to ensure a proper level of precision in searching. Such possible techniques are considered. 相似文献
7.
产气荚膜梭茵（Clostridium perfringens）是一种重要的人兽共患病的病原体，它是一类革兰氏阳性产芽孢的厌氧梭茵，可引起人的食物中毒和肠毒素相关腹泻。近年来，研究人员发现由产气荚膜梭茵导致腹泻的主要原因与该茵在芽孢形成过程中产生的一种肠毒素有关。文章重点针对产气荚膜梭茵肠毒素的生物学特性和致病机制等方面的研究做一综述。 相似文献
8.
Paskin R 《Australian veterinary journal》2011,89(Z1):89-91
The equine influenza outbreak detected in August 2007 in New South Wales and Queensland did not enter Victoria, which was, however, considered at risk because of its sizable border with New South Wales. Accordingly, Victoria implemented a response plan to prevent disease entry and enable early detection of any disease. Horse movement restrictions, surveillance strategies and public awareness formed a large part of this response. 相似文献
9.
产气荚膜梭菌肠毒素的分子生物学研究进展 总被引：1，自引：0，他引：1
产气英膜梭菌(Clostridium perfringens)是一种重要的人兽共患病的病原体,它是一类革兰氏阳性产芽孢的厌氧梭菌,可引起人的食物中毒和肠毒素相关腹泻.近年来,研究人员发现由产气英膜梭菌导致腹泻的主要原因与该菌在芽孢形成过程中产生的一种肠毒素有关.文章重点针对产气英膜梭菌肠毒素的生物学特性和致病机制等方面的研究做一综述. 相似文献
10.
牙周病(periodontal disease, PD)是由细菌在牙齿表面聚集形成的牙菌斑和牙结石逐渐侵蚀牙周组织,引发周围组织炎症的一类疾病。根据疾病的发展进程,可分为齿龈炎与牙周炎2个阶段。在小动物临床疾病中牙周病尤为常见,世界范围内约有80%的成年犬患有该病。由于饲主对于犬的口腔保健意识薄弱且该疾病隐秘性较高,患犬就诊时往往已出现牙周支持组织不可逆的损伤,细菌及其毒力因子通过血液循环进入全身从而引发系统性疾病的风险大大提高。但目前犬牙周病的核心致病菌属、菌群失调的原因与发病机制尚不明确。因此,笔者基于高通量测序方法的病原学研究结果,分析与疾病发展相关的微生物群。同时,整合目前世界通用的最新犬牙周病临床诊断分级标准及犬牙周病的中西医防治方案,分析犬牙周病与全身系统性疾病之间的相关性,系统综述犬牙周病在国内外小动物临床领域的研究进展,以期为该类疾病的临床诊疗提供理论参考,推进兽医师在临床实践中更高效地开展该类疾病的诊疗工作,并为犬牙周病相关的临床研究提供思路。 相似文献
11.
Asuka Kumagai Kyoko Kawauchi Kiyohiko Andoh Shinichi Hatama 《Journal of veterinary diagnostic investigation》2021,33(1):162
Bovine respiratory syncytial virus (BRSV) is an etiologic agent of bovine respiratory disease. The rapid evolutionary rate of BRSV contributes to genetic and antigenic heterogeneity of field strains and causes occasional vaccine failure. We conducted molecular epidemiologic characterization of BRSV circulating in Japan to obtain genetic information for vaccine-based disease control. Phylogenetic analysis of G and F gene sequences revealed that all of the isolated Japanese BRSV strains clustered in the same genetic subgroup, which was distinct from the 9 known groups. We assigned the Japanese group to subgenotype X. The Japanese isolates formed 2 temporal clusters: isolates from 2003 to 2005 clustered in lineage A; isolates from 2017 to 2019 formed lineage B. The alignment of the deduced amino acid sequences of the G gene revealed that the central hydrophobic region responsible for viral antigenicity is conserved in all of the isolates; unique amino acid mutations were found mainly in mucin-like regions. Our results suggest that BRSV has evolved uniquely in Japan to form the new subgenotype X; the antigenic homogeneity of the viruses within this group is inferred. 相似文献
12.
Aland A Kaart T Poikalainen V Praks J 《DTW. Deutsche tier?rztliche Wochenschrift》2005,112(12):474-476
An important precondition of a well-functioning dairy production is knowledge about the incidence of environmentally evoked non-infectious diseases in a particular herd, in the region and in the country as a whole. The aim of this study was to determine the incidence rate of environmentally evoked multifactorial diseases in Estonian dairy herds, and to compare the disease incidence in small (< or = 100 cows) and large herds (101-300 cows). The disease incidence was recorded by local veterinarians in twelve production units with a total of 33 cowsheds and about 5000 dairy cows. Fourteen disease groups were formed. In order to describe the range of disease incidence, the relative frequency of each group of diseases was determined, as well as the incidence rate. The 95 % confidence interval was applied in order to assess the reliability of the incidence rates. The most common disorders of Estonian dairy cows are udder diseases, followed by uterine infection, metabolic diseases and retained placenta. The disease incidence in Estonian dairy herds is similar to that of other European countries. Most of the diseases occur more often in small herds than in large herds. 相似文献
13.
A flock of 4,500 Cobb broilers inoculated with Newcastle disease vaccine intra-ocular strain B1 type at 10 days of age developed clinical signs of the disease 19 days later; the mortality rate was 71%. Necropsy examinations showed characteristic lesions. Newcastle disease virus was isolated and identified in the allantoic fluid of embryonating chicken eggs by haemagglutination and haemagglutination-inhibition tests. Histopathological examination showed that follicles of the bursa were depleted of lymphocytes, had many large cavities and were being repopulated by newly formed healthy lymphocytes. Both the acute and convalescent serum samples were positive for infectious bursal disease antibodies in agar gel precipitation tests. Haemagglutination inhibition titres of the acute and convalescent sera were 20 to 80 and 80 to 640 respectively. The vaccine failure may be due to either the subclinical bursal disease or the highly pathogenic nature of the wild Newcastle disease virus. 相似文献
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15.
In an attempt to compare the equine grass sickness as reported in Europe with that described in the Republic of Colombia, sera from horses experiencing grass sickness in Scotland were used in neutralisation tests with Clostridium perfringens type A enterotoxin. The sera, from acute and chronic cases of the disease, failed to neutralise either crude or partially-purified enterotoxin. Neither were precipitin lines formed when the sera were treated against the toxin in immunoelectrophoresis. These results suggest that grass sickness in Europe and the equine disease in Colombia have a different aetiology. 相似文献
16.
Watanabe K Kikuchi M Okumura M Kadosawa T Fujinaga T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(9):1007-1010
Enamel matrix protein (EMP) was applied for regeneration of periodontal tissue in 2 dogs with spontaneous periodontal disease. Case 1 had bony resorption around the root and root apex of the maxillary fourth premolars. Case 2 had vertical resorption of bone between the mandibular first and second molars. A flap was formed in the buccal gingiva, and EMP was applied onto the surface of the exposed root. One or 4 months postoperatively, increased bone level and clinical attachment were recognized. EMP was therefore suggested to be effective to induce regeneration of periodontal tissues in the cases with periodontal disease. 相似文献
17.
Samartino LE 《Veterinary microbiology》2002,90(1-4):71-80
Brucellosis has been recognized in Argentina since the 19th century. Several studies demonstrated the presence of the disease in most of the domestic species. Actually, the estimate of prevalence is that between 10 and 13% of the farm animals are infected with bovine brucellosis with an individual rate of 4–5%. The annual economical losses have been estimated at US$ 60,000,000. The control of bovine brucellosis began in 1932 and successive resolutions have been issued since then. The current resolution indicates that B. abortus S19 is mandatory in female calves between 3 and 8 months of age. The vaccine strain B. abortus RB51 was provisionally approved but only for cattle older than 10 months of age. The brucellosis control program consists principally of test and slaughter. This methodology has been successful mainly in the dairy farms that have the incentive due to increased pricing because of obtaining a low prevalence of the disease. Brucellosis has been found in porcine, caprine, ovine and canine species. All Brucella species have been found in the country. Human brucellosis is an important disease and a national coordinated diagnostic net has been formed to better control the disease in man. 相似文献
18.
Wellehan JF Childress AL Marschang RE Johnson AJ Lamirande EW Roberts JF Vickers ML Gaskin JM Jacobson ER 《Veterinary microbiology》2009,133(1-2):34-42
The orthoreoviruses are segmented RNA viruses that infect diverse vertebrate host species. While the most common human orthoreovirus, Mammalian Reovirus, is not typically associated with significant disease, the majority of Orthoreovirus species have been shown to cause significant and often fatal disease in reptiles, birds, and primates. There is significant potential for jumping species. A consensus nested-PCR method was designed for investigation of the RNA-dependent RNA polymerase gene of Orthoreovirus and Aquareovirus. This protocol was used to obtain sequencing template from reoviruses of three different vertebrate classes. Bayesian and maximum likelihood phylogenetic analysis found that all viruses analyzed clustered in the genus Orthoreovirus, that reptile reoviruses formed three distinct clusters, and that an African grey parrot reovirus clustered with Nelson Bay virus from bats. This PCR method may be useful for obtaining templates for initial sequencing of novel orthoreoviruses from diverse vertebrate hosts. 相似文献
19.
DIANA L. JONES DVM MVSc Diplomate ACVS SPENCER M. BARBER DVM Diplomate ACVS SHERMAN W. JACK dvm MS PhD CECIL E. DOIGE dvm PhD 《Veterinary surgery : VS》1994,23(4):231-240
Gross and microscopic effects of arthroscopic partial synovectomy on synovium and articular cartilage of middle carpal joints were studied in 15 horses. A 7-mm diameter motorized synovial resector was inserted into each middle carpal joint and arthroscopic partial synovectomy and lavage or arthroscopic lavage alone was performed. Study periods were 0 (three horses), 16 (three horses), and 30 days (six horses). No gross evidence of degenerative joint disease was observed at day 16 or 30. At 30 days, resected areas lacked villi and there was deposition of fibrin on the synovial surface with varying amounts of newly formed fibrovascular tissue. Thirty days after arthroscopic synovectomy, normal synovium had not formed in equine middle carpal joints. 相似文献
20.
Three contagious poultry diseases in Mauritania were studied. Serum samples and tracheal swabs were taken from 80 chickens in village poultry flocks in each of three different regions. Antibodies against Newcastle disease virus (NDV) were detected in 4.8% of chickens, antibodies against Gumboro disease virus in 15.8% of chickens and antibodies against Salmonella pullorum in 6.2% of chickens. Six isolates of NDV were made, of which four formed plaques on chicken embryo fibroblast monolayers. Seropositivity was highest in the Trarza region, bordering the River Senegal, and four out of six of the NDV isolates were made from chickens in this region. 相似文献