丹参根腐病拮抗细菌筛选、鉴定及生防机理研究          下载免费PDF全文

许乐  王子强  张爽  邢倩  刘丽娜  洒荣波 《中国生物防治学报》2021,37(4):846-854

腐皮镰刀菌Fusarium solani造成的根腐病是丹参主要土传病害之一。本研究采用稀释涂布平板法从丹参植株中分离筛选得到一株对根腐病具有良好防治效果的内生拮抗菌株DS-R5,经形态学和分子生物学鉴定为多粘类芽胞杆菌Paenibacillus polymyxa。通过孢子萌发试验、光学显微镜观察、扫描电镜和透射电镜观察,研究菌株DS-R5对腐皮镰刀菌的抑制机制。结果显示,菌株DS-R5抗菌活性物质粗提物对腐皮镰刀菌孢子萌发具有明显的抑制作用;受抑制菌丝发生畸变,菌丝缠绕、断裂,局部出现断裂;扫描电镜观察发现,受抑制菌丝大量断裂,有菌丝碎屑产生,菌丝粗细不一,表面粗糙,有胞内物质泄露;透射电镜观察显示,菌丝体细胞畸形,无完整细胞器存在,胞质外流,内部出现异常空洞。盆栽试验结果显示,菌株DS-R5对丹参根腐病的防治效果达到61.4%。综上,菌株DS-R5对丹参根腐病具有较好的生防潜力,具有进一步开发的前景。  相似文献   

昭通黄牛遗传资源调查报告   总被引：1，自引：0，他引：1  

覃兴合  黄伟  撒义东  刘文斌  凤其友  周典双  张光能  曾孝元 《中国牛业科学》2009,35(4):69-74

[目的]为全面掌握昭通黄牛资源状况,做好该品种的保护和开发利用工作.[方法]调查按国家畜禽遗传资源管理委员会<畜禽遗传资源调查技术手册>技术规范执行,采用普查,实地走访、观察、抽样测定,查阅相关文献资料等方式,了解产区概况、品种来源与发展方向、外貌特征、体尺体重、生产性能、饲养方式、繁殖性能等,并进行综合评定.[结果]昭通黄牛具有体质健壮、肉质良好、抗旱耐湿、耐粗抗病、性情温顺、适应性强、行动敏捷、产肉性能好、皮板质量优良等特点,但自20世纪80年代以来,随着外引牛冻精开展肉用杂交面的扩大,纯种数量逐年减少,产区各地都在强行对昭通黄牛公牛实行阉割,致使该品种正以地区级的规模被取代.[结论]昭通黄牛属于南方黄牛,是云南黄牛的三个地方类群之一,屠宰率和净肉率高于本省的其他品种牛,其具有较高的遗传变异和丰富的遗传多样性,同时与瘤牛发源息息相关,有特殊的起源地位,选育、保种工作亟待重视和加强.  相似文献   

Sulfur-associated polioencephalomalacia in cattle grazing plants in the Family Brassicaceae     

RA McKenzie  AM Carmichael  ML Schibrowski  SA Duigan  JA Gibson  JD Taylor 《Australian veterinary journal》2009,87(1-2):27-32

Polioencephalomalacia was diagnosed histologically in cattle from two herds on the Darling Downs, Queensland, during July–August 2007. In the first incident, 8 of 20 18-month-old Aberdeen Angus steers died while grazing pastures comprising 60% Sisymbrium irio (London rocket) and 40% Capsella bursapastoris (shepherd's purse). In the second incident, 2 of 150 mixed-breed adult cattle died, and another was successfully treated with thiamine, while grazing a pasture comprising almost 100% Raphanus raphanistrum (wild radish). Affected cattle were either found dead or comatose or were seen apparently blind and head-pressing in some cases. For both incidents, plant and water assays were used to calculate the total dietary sulfur content in dry matter as 0.62% and 1.01% respectively, both exceeding the recommended 0.5% for cattle eating more than 40% forage. Blood and tissue assays for lead were negative in both cases. No access to thiaminase, concentrated sodium ion or extrinsic hydrogen sulfide sources were identified in either incident. Below-median late summer and autumn rainfall followed by above-median unseasonal winter rainfall promoted weed growth at the expense of wholesome pasture species before these incidents.  相似文献   

Rate of decline of chlorfluazuron concentration in the fat of cattle   总被引：1，自引：0，他引：1  

SA SPENCE  R. MURISON  S. HARDEN 《Australian veterinary journal》1998,76(1):54-56

Objective To determine the rate of decline of chlorflu-azuron (CFZ) concentration in the fat of cattle.
Design A field depletion study.
Animals Fifteen steers that had become contaminated with CFZ through eating cotton trash or cotton leaf pellets derived from CFZ-treated cotton crops.
Procedure Fat samples were collected from the cattle at about 3 week intervals according to a schedule where each animal was sampled on four occasions up to 340 days after removal from the contaminated feed source.
Results When the effects of dilution are removed CFZ concentrations were found to decline slowly for about 200 days. Depletion was minimal between 200 and 340 days.
Conclusion According to this trial, CFZ-contaminated, non-lactating cattle which have finished growing will remain contaminated. Field experience has not supported this conclusion.  相似文献   

单板层积材在线检测系统硬件抗干扰措施   总被引：1，自引：0，他引：1  

肖江  俞国胜  撒潮  陈锋军 《林产工业》2008,35(5)

1引言单板层积材是单板经涂胶、顺纹组坯后热压而成的多层板材。按应用领域的不同一般分为非结构型和结构型两种。结构型单板层积材也称为木质工程结构单板层积材,是强制限定力学性能、用于制作承载结构部件的结构板材,要求具有较好的结构稳定性和耐久  相似文献   

Effect of 0.1, 0.2, 0.4, and 0.8 mg kg⁻¹ of intravenous butorphanol on thermal antinociception in cats     

SA Robertson †  BDX Lascelles‡  PM Taylor§ 《Veterinary anaesthesia and analgesia》2003,30(2):107-107

Many cats do not receive analgesics for treatment of perioperative pain, but when they do, the opioid agonist–antagonist butorphanol (B) is widely used. B is reported to provide long‐lasting visceral analgesia, but its somatic actions are not well documented. This study aimed to assess B by using a thermal threshold (TT) model. Six cats (four spayed females, two castrated males, 4.4–6.9 kg) participated in the study. The day before each study, the lateral thorax of each of the cats was shaved and a cephalic catheter was placed. TT was measured using a thermal threshold testing device specifically developed for cats. A heater element and temperature sensor housed in a small probe was held against the cat's thorax with an elastic band and pressure bladder to assure consistent contact. Skin temperature was recorded before each test, then the heater was activated. When the cat responded by flinching, turning, or jumping, the stimulus was terminated and the threshold temperature recorded. A cut‐out temperature was set at 55.5 °C. Three baseline measurements were recorded before IV injections of 0.1, 0.2, 0.4, or 0.8 mg kg^?1 of B. Each cat received all doses in a randomized order at least 1 week apart, and the investigator was blinded to the treatments. TT was measured at every 15 minutes for 6 hours. Data were analyzed using a three‐factor anova , and the critical mean difference was calculated. Pre‐treatment threshold was 40.8 ± 2.25 °C in all cats. There was a significant increase in threshold in all groups from 15 to 90 minutes, but no dose‐related differences were observed. Peak threshold achieved was 48.35 °C, 60 minutes after 0.4 mg kg^?1 of B was injected. Mydriasis was present in all cats after treatment, and many exhibited dysphoric behavior. In this model, B had a short duration of action and no dose–response relationship. Compared to other opioids tested under similar conditions, the intensity of the effect of B was small and of shorter duration.  相似文献   

Identification of equine herpesvirus 3 (equine coital exanthema virus), equine gammaherpesviruses 2 and 5, equine adenoviruses 1 and 2, equine arteritis virus and equine rhinitis A virus by polymerase chain reaction     

K DYNON  A VARRASSO  N FICORILLI  SA HOLLOWAY  GH REUBEL  F LI  CA HARTLEY  MJ STUDDERT  HE DRUMMER 《Australian veterinary journal》2001,79(10):695-702

OBJECTIVE: To develop rapid (< 8 hour) tests using polymerase chain reaction (PCR) for the diagnosis of equine herpesvirus 3 (EHV3; equine coital exanthema virus), equine gammaherpesviruses 2 (EHV2) and EHV5, equine adenovirus 1 (EAdV1), EAdV2, equine arteritis virus (EAV), equine rhinitis A virus (ERAV; formerly equine rhinovirus 1) DESIGN: Either single round or second round (seminested) PCRs were developed and validated. METHODS: Oligonucleotide primers were designed that were specific for each virus, PCR conditions were defined and the specificity and sensitivity of the assays were determined. The application of the tests was validated using a number of independent virus isolates for most of the viruses studied. The PCRs were applied directly to clinical samples where samples were available. RESULTS: We developed a single round PCR for the diagnosis of EHV3, a seminested PCR for EHV2 and single round PCRs for EHV5, EAdV1, EAdV2 and RT-PCRs for EAV and ERAV. The PCR primer sets for each virus were designed and shown to be highly specific (did not amplify any recognised non-target template) and sensitive (detection of minimal amounts of virus) and, where multiple virus isolates were available all isolates were detected. CONCLUSION: The development and validation of a comprehensive panel of PCR diagnostic tests, predominantly for viruses causing equine respiratory disease, that can be completed within 8 hours from receipt of clinical samples, provides a major advance in the rapid diagnosis or exclusion diagnosis of these endemic equine virus diseases in Australia.  相似文献   

青海省黄南州泽库、河南两县畜牧生产调查报告     

吉生宏  罗晓林  魏雅萍  石德军  洒文君  格日多杰  陈玉文 《中国牛业科学》2005,31(1):31-34

本文通过对泽库，河南两县的两个示范村的实地调查研究，对畜牧业发展现状的分析，提出了在该地区家畜改良的具体措施。  相似文献   

The rate of decline of α- and β- benzene hexachloride residues in contaminated pigs     

SA SPENCE  EB DETTMANN  JM WILSON 《Australian veterinary journal》1992,69(1):17-18

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Production responses to internal parasite control in dairy cattle     

SA SPENCE  GC FRASER  EB DETTMANN  DF BATTESE 《Australian veterinary journal》1992,69(9):217-220

A significant increase in milk production, averaging 164 litres per cow per lactation (a 4.8% increase), was seen after cows infected with gastrointestinal nematodes, paramphistomes and Fasciola hepatica were treated with broad-spectrum anthelmintics. Three hundred and ninety pairs of cows from eight herds with year-round calving were studied. One cow in each matched pair was given 7.5 mg/kg fenbendazole, 7.5 mg/kg levamisole hydrochloride and 15 mg/kg oxyclozanide in March, May and August of one year; the other cow in the pair received no anthelmintic. The number of nematode and trematode eggs was significantly decreased in the faeces of treated cows.  相似文献