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1.
猪抗病育种研究进展   总被引:7,自引:2,他引:5  
作者对开展抗病育种的必要性、发展过程、抗病的遗传基础、抗病育种方法的现状及存在的问题进行了介绍。其中对MHC、抗病主基因、抗病育种的直接、间接方法、转基因抗病育种进行了重点介绍,提出采用分子标记辅助选择和转基因工程抗病育种是当前和今后抗病育种的主要方向,最后对抗病育种将来的发展前景进行了展望。  相似文献   

2.
樱桃根癌病是由根癌土壤杆菌引起的一种危险性细菌性病害。樱桃根癌病在泸定县为高度危险性病害,R=2.08。MaxEnt生态预测表明泸定县的田坝乡、冷磧镇、兴隆镇为樱桃根癌病的发生区,和野外调查结果基本一致;德威乡、杵坭乡、田坝乡大部分地区为高度危险区,得妥乡、加郡乡、新兴乡及烹坝乡为适生区,其他为不可能发生区。泸定县要加强检疫,严禁带菌苗木进入境内。一旦发现感病植株,应及时清除,防止进一步扩散。  相似文献   

3.
Epistaxis was retrospectively evaluated in 35 dogs. Systemic disease was diagnosed in seven dogs and intranasal disease in 29. Nineteen dogs with intranasal disease had neoplasia. Dogs with neoplasia were older (mean 10.0 years) than dogs with nonneoplastic intranasal disease (mean 5.6 years). Signs persisting for >1 month occurred more often in dogs with intranasal than systemic disease. Unilateral epistaxis did not distinguish intranasal from systemic disease. Only dogs with intranasal disease had facial deformity, decreased airflow, or regional sub-mandibular lymphadenopathy. Dogs with systemic disease had a lower packed cell volume (mean 31.8%) than dogs with intranasal disease (mean 42.7%).  相似文献   

4.
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   

5.
兔病毒性出血症研究进展   总被引:3,自引:0,他引:3  
兔病毒性出血症俗称"兔瘟",是由兔病毒性出血症病毒引起的一种急性,致死性传染病,对易感兔致病率可达90%,病死率可高达100%。文章对兔病毒性出血症的病原学、流行病学、临床症状、病理变化、诊断和防制研究进展作了系统深入综述,并提出了存在的问题和展望。  相似文献   

6.
水貂阿留申病(Aleutian disease of mink,ADM)是由水貂阿留申病细小病毒(Aleutian mink disease parvovirus,AD-MV)引起的一种慢性、进行性传染病,一直是危害世界养貂业健康发展最重要的疫病之一。到目前为止,还没有疫苗可成功用于ADM的预防,也没有特异有效的治疗方法,唯一可行的防治方法就是通过多次特异性检疫,淘汰病貂,净化貂群。笔者对阿留申病的病原学、发病机制、防治措施等方面进行概述,为临床防治水貂阿留申病提供了理论基础。  相似文献   

7.
近年来,随着水貂养殖行业的不断发展,一些疫病也成为了制约水貂养殖业发展的重要因素。水貂阿留申病作为毛皮动物的三大疫病之一(阿留申病、犬瘟热、病毒性肠炎),是导致母貂产仔率下降、公貂配种能力降低和毛皮质量下降的一种高度接触性传染病。至今为止,还没有商品化的疫苗来控制该病的传播及蔓延。控制水貂阿留申病最好的方法是通过检测淘汰所有抗体为阳性的水貂,进而达到净化貂群的目的。而在抗体检测过程中,诊断抗原的制备和纯化决定着检测方法的敏感性、特异性和准确性。论文对目前阿留申病毒细胞抗原及基因工程抗原研究进展做一综述,为今后该病病原检测工作提供参考。  相似文献   

8.
试验采用口蹄疫O型间接血凝试验和O型口蹄疫抗体液相阻断ELISA 2种试验方法检测了60份血清中猪O型口蹄疫免疫抗体.研究结果显示,60份被检血清口蹄疫O型间接血凝试验检测合格率为93.3%,O型口蹄疫抗体液相阻断ELISA试验检测的合格率为73.3%,口蹄疫O型间接血凝试验检测合格率明显高于O型口蹄疫抗体液相阻断ELISA试验检测的合格率(相差20个百分点);2种方法的总符合率为66.7%、<25(<2^6)的符合率为28.6%,≥2^5(≥2^6)的符合率为82.1%.2种方法检测出的整体免疫效果较好,平均合格率远高于农业部规定的70%.  相似文献   

9.
蓝舌病为OIE规定的需通报疫病,我国将其列为一类动物疫病。该病已经给全球大部分流行地区造成巨大经济损失。我国于1979年首次证明该病存在,且在我国流行初期即造成大量易感动物死亡,给我国畜牧业带来了重大经济损失。但蓝舌病在我国仍属冷门研究方向,我国到底分离鉴定出多少个血清型的蓝舌病病毒,该病在我国的分布范围到底有多广?许多畜牧兽医工作者对这些问题并不是非常清楚。特别是在近年来鲜有蓝舌病引起动物发病死亡报道的前提下,人们对蓝舌病的重视程度进一步降低。本文对蓝舌病在全球的流行概况进行简要阐述,同时,对蓝舌病在我国40年的流行情况进行回顾,希望该病在我国能够得到足够的重视。  相似文献   

10.
From 1980 to 1988 235 koalas were necropsied and 67 were found to have urinary tract disease. Six affected koalas out of 48 were derived from wildlife parks around Sydney while 61 of 187 were derived from free living populations on the central and north coasts of New South Wales. Sixteen had cystitis alone, 5 had cystitis and associated renal disease only, 16 females had cystitis with genital disease, 23 had urinary disease in combination with other systemic disease and 7 had renal disease only. Overall 49 animals had cystitis (30 females and 19 males; 47 being free living) with 12 of these having renal extension (all free living). Cystitis tended to be active but chronic while associated renal disease was mainly designated as hydronephrosis and pyelonephritis. Other forms of renal disease included lymphosarcoma, oxalate nephrosis, acute and chronic nephritis, and microabscessation related to septicaemia. Female genital disease associated with cystitis was commonly vaginitis and metritis. Paraovarian cysts were detected with and without metritis. Other diseases occurring with urinary tract disease included conjunctivitis, dermatitis/stomatitis, pneumonia and hepatic disease. The higher prevalence of urinary tract disease in free living koalas, especially cystitis, is in contrast to captive koalas and may reflect the interaction between disease cause and habitat.  相似文献   

11.
Companion exotic mammal herbivores may be diagnosed with chronic disease that the owner believes is causing acute clinical illness. It is generally believed that because of the enhanced disease-masking ability of these “prey” species, numerous disease states may go unnoticed for a significant period. A veterinarian should be knowledgeable about this behavior trait and consider its possible effects when assessing the patient's health status. In some cases, the chronic disease condition may respond rapidly to treatment, whereas with other diagnoses, treatment is more frustrating. This article describes a selection of chronic disease conditions that one may diagnose in guinea pigs (e.g., hypovitaminosis C, trixacariasis, urolithiasis, dental disease), chinchillas (e.g., dental disease), and rabbits (e.g., dental disease, renal failure, cranial thoracic mass disease). Gastrointestinal and cardiovascular disease problems diagnosed in companion exotic mammal herbivores are covered elsewhere in this journal issue.  相似文献   

12.
牛只饲养过程中,消化系统疾病具有较高的发病率,其会在较大程度上影响牛只的生长与繁殖。牛只患病后,将会显著降低采食欲望,生长发育速度减缓,甚至还会有死亡问题出现,进而严重损害到养殖户的经济利益。针对这种情况,需总结牛消化系统疾病的常见类型,提前采取针对性的预防措施,促使牛消化系统疾病的发病率得到降低。  相似文献   

13.
A field trial was set up to determine the effects of mechanical shortening of long incisors (bite correction) of ewes with early periodontal disease on the progress of the disease and on their body weights. On a farm near Te Anau with a high prevalence of periodontal disease in sheep, the body weights of 75 sound mouth ewes and two groups each of 75 ewes with periodontal disease were recorded. At the start of the trial, the incisors of the ewes in one of the groups with periodontal disease were shortened using a grinder. The trial ran for 2 years. The mouths of almost all the sheep which had sound mouths at the start of the trial remained sound throughout. This suggests that on periodontal disease-prone farms it may be possible to select ewes at 3 or 4 years of age which will retain sound mouths throughout much of thei-r productive lives. Throughout the trial, sheep with advanced periodontal disease tended to be lighter than sheep with mild periodontal disease and those in turn tended to be lighter than sheep with sound mouths. Mechanical shortening of the incisors did not alter the proportion which subsequently developed advanced periodontal disease. Seventeen to eighteen percent of ewes in both periodontal disease groups had developed advanced periodontal disease by the end of the trial. There was no significant difference in body weight between the group with shortened incisors and the group with untreated periodontal disease. Consequently, the trial provides no evidence that the mechanical shortening of the incisors of ewes will improve their productivity.  相似文献   

14.
Three hundred and ten cats that had CT imaging of the head between January 2000 and December 2007 were evaluated retrospectively. Data that were recorded included signalment, presenting complaint, clinical signs, presence of upper respiratory tract disease, and CT findings. One hundred and one cats had evidence of middle ear disease on CT. Thirty-four of the 101 cats (34%) did not have a primary complaint of ear-related disease, clinical signs or physical findings consistent with ear disease, suggesting that the middle ear disease was subclinical. Twenty-seven of the 34 cats (79%) had concurrent nasal disease. Middle ear lesions were chronic in appearance. With the exception of tympanic bulla lysis, CT findings were similar in cats presenting with primary aural disease versus cats with presumptive subclinical middle ear disease. The majority of the cats did not return for treatment of the identified middle ear abnormalities. Subclinical middle ear disease is relatively frequent in cats undergoing CT imaging of the head. Few cats required subsequent treatment for ear disease although follow up was limited. Identification of subclinical middle ear abnormalities on CT should prompt acquisition of a detailed patient history and bilateral otoscopic examination.  相似文献   

15.
畜牧业是张掖市的支柱产业,面对当前动物疫病防控形势依然严峻的现状,创建无疫小区是保障畜牧业持续稳定发展的必由之路,我市的规模养殖比重达较大,创建无疫小区的基础好,通过认真分析我市养殖现状和动物疫病防控形势后,针对创建养殖场无疫小区提出了出台扶持政策、加强宣传引导和落实管控措施的思路与对策,为我市创建无疫小区和无疫区,更好地做好动物疫病防控工作,保持畜牧业增收势头更强劲提出可供参考的建议。  相似文献   

16.
牛口蹄疫是国家一类重特大传染性疾病,会严重威胁地区牛养殖产业的安全,给养殖户带来巨大经济损失,降低牛养殖产业的生产效益。再加上牛口蹄疫是一种人畜共患病,疾病传播流行中,如果没有做好个体防护很易造成病毒,向人扩散蔓延,威胁周边居民的生命财产安全。在充分掌握牛口蹄疫病发生现状的基础上,需要进行认真细致的分析,构建针对性的防控措施,降低疾病发生流行造成的危害。在充分掌握新宾县牛口蹄疫发生现状的基础上,对牛口蹄疫疾病的诊断和提出防治措施。  相似文献   

17.
番鸭呼肠病毒病是由番鸭呼肠病毒引起的一种急性传染病,主要发生于40日龄内的番鸭,临床上以软脚为主要症状,并伴有腹泻,发病率高,病情严重时可致全群死亡,给番鸭养殖业带来了巨大的损失。其病原为呼肠病毒科正呼肠病毒属番鸭呼肠病毒。文章综合了国内外对该病的病原学研究成果,从病毒的分类地位、生物学特性、基因组与编码蛋白、病原分布及流行特性、检测与防控等方面对该病的病原学进行了较全面的论述,以期对该病的深入研究和防控提供有用的资料。  相似文献   

18.
白粉病是沙打旺的一种主要病害,高温、潮湿季节发病率较高,危害较严重。发病初期用粉锈宁喷雾防治,可以有效地控制病害的扩散蔓延,防治效果达到74.9%。  相似文献   

19.
牛结节性皮肤病是一种急性、亚急性传染性疾病。由于养殖户不科学地引种行为,造成该类疾病从其他国家引入本地区。牛结节性皮肤病又被称为牛结节疹、牛结节性皮炎或者牛疙瘩皮肤病,是由结节性皮肤病毒引发的一种急性亚急性传染性疾病。该类疾病被世界动物卫生组织规定为必须通报的疾病,我国将其划归为一类重大动物疫病。牛结节性皮肤病首先发生于新疆地区,随后由于不科学的运输和引种造成该类疾病,呈现逐渐扩大蔓延的趋势,带来的损失十分严重。需要掌握牛结节性皮肤病的具体流行特点、临床表现,做到及时发现及时处置,控制疫情的传播蔓延,确保我国牛养殖安全。该文主要论述牛结节性普皮肤病的诊断和防控。  相似文献   

20.
鸡新城疫是由鸡新城疫病毒引起的一种急性、高度接触性传染病,致死率较高。目前,我国普遍采用以新城疫疫苗接种为主的综合防控措施,能够在很大程度上控制该病的大规模流行。鸡大肠杆菌病是由大肠埃希菌感染引起的传染病,多个血清型的大肠埃希菌是多种动物肠道内的常驻菌,因此其分布极为广泛,致病率也较高,并且多与其他疫病混合感染。通过开展病死鸡的病理变化检查、实验室检验以及分离菌株的药物敏感性试验,对临床接诊的鸡新城疫及大肠杆菌混合感染病例进行诊断并提出综合防控措施,以期为兽医临床2种疾病的防控提供有益参考。  相似文献   

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