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11.
随着我国加入世界贸易组织 ,对外开放的程度、范围进一步加深和扩大 ,我国动物防疫工作面临着与世界接轨的问题 ,不仅要做到有效地控制畜禽传染病 ,保护畜牧业安全和人民身体健康 ,也需要得到国际社会的认可 ,为我国畜牧业和畜产品打入国际市场提供技术保障 ,创造其环境、信誉优势。为此 ,笔者认为应建立我国动物防疫形象识别系统 ,通过规范的管理、统一的标识、共同的理念和标准的行为 ,全面提升政府部门的动物防疫整体形象 ,提高社会对动物防疫机构的信赖度和认知度 ,树立良好的国际形象和声誉。1形象识别系统的概念形象识别系统英文名称…  相似文献   
12.
影响饲料制粒的因素及其控制方法分析   总被引:4,自引:0,他引:4  
影响制粒的因素很多,有制粒机自身性能、待制粒原料理化性质、生产操作和工艺条件等。本文从饲料组分、物料理化性质、配方组成、压模和压辊等几个方面作了简要阐述,为提高饲料制粒效率,保证制粒质量提供参考。  相似文献   
13.
OBJECTIVE: To assess whether site-related changes in biochemical composition are present in the cartilage and subchondral and trabecular bone of the metacarpophalangeal joint of horses with early osteoarthritis. SAMPLE POPULATION: Right metacarpophalangeal joints from 59 mature warmblood horses. PROCEDURE: Biochemical data (cross-link, amino acid, DNA, and ash contents; denatured collagen and glycosaminoglycan [GAG] concentrations; bone mineral density; and mineral composition) were obtained from 2 differently loaded sites of phalanx I cartilage and subchondral and trabecular bone samples; data were compared with previously published values from nonosteoarthritic equine joints. RESULTS: Compared with findings in nonosteoarthritic joints, GAG concentration was lower in cartilage from osteoarthritic joints and there was a loss of site differences in cellularity and lysylpyridinoline (LP) cross-link content. In subchondral bone, LP cross-link content was decreased overall and there was a loss of site differences in osteoarthritic joints; ash content was higher in the osteoarthritic joints. Hydroxyproline content in trabecular bone from osteoarthritic joints was greater than that in nonosteoarthritic trabecular bone. In all 3 layers and at both sites, the linear increase of the pentosidine cross-link content with age had diminished or was not apparent in the horses with osteoarthritic joints. CONCLUSIONS AND CLINICAL RELEVANCE: In equine metacarpophalangeal joints with early osteoarthritis, distinct biochemical changes were detected in the cartilage and subchondral and trabecular bone. The dissimilarity in response of the different tissues and differences between the sites that are affected may be related to differences in biomechanical loading and transmission and dissipation of force.  相似文献   
14.
规模猪场母猪繁殖障碍综合征的病因调查   总被引:3,自引:0,他引:3  
作者采用9套试剂盒,检测了7种能引起猪繁殖障碍综合征的传染病,对来自有繁殖障碍症状的305场次进行猪瘟(HC)抗原检测,并对包括这305场次在内的978个猪场(次)病例的6346份血清样品及52698份田间血清样品进行HC、猪繁殖与呼吸综合征(PRRS)、伪狂犬病(PR)、日本乙型脑炎(JE)、细小病毒感染(DPV)、猪衣原体病(Chla)、布鲁氏菌病(Bruc)等7种传染病的抗体检测。结果表明,在有繁殖障碍症状的猪场,HC抗原检出率高达61.97%,并且在不使用疫苗的情况下,PR3RS、PR、JE、Chla和PPV的抗体阳性场分别为49.42%、34.29%、12.72%、31.71%、和48.08%。HC和:PR交叉感染率达23.81%;HC和:PRRS交叉感染率为9.52%,PR和PRRS交叉感染率高达59.65%;另外JE、PPV也同HC、PR、PRRS存在部分交叉感染。不使用疫苗的田间血清样品的PRRS、PR的抗体阳性率也高。HC与PRRS.PR、Chla、JE和PPV中的一种或几种混合感染可能是引起繁殖障碍造成严重损失的主要原因。加强综合防制,优化免疫程序、把握引种关、加强生物安全措施是防制猪繁殖障碍综合征的关键。  相似文献   
15.
The use of reticulo-rumen temperature boluses to detect bovine respiratory disease (BRD) was investigated in young bulls following their entry into a fattening unit. Twenty-four bulls received a bolus at entry and were observed for 40 days. As soon as a reticulo-rumen hyperthermia (RH) episode was detected using the bolus, clinical examination was performed by a veterinarian and then repeated every 12-24h until the end of RH episode. Fifty-two RH episodes were detected in 22 animals. High rectal temperatures (40.1±0.6°C) were observed during these episodes. BRD was diagnosed on the basis of clinical examination during 38/52 RH episodes in 21 animals (positive predictive value 73%). The onset of BRD signs always occurred after the onset of RH episodes, with a time-lag from 12 to 136 h, depending on BRD signs. Monitoring reticulo-rumen temperature permits early detection of BRD; however, clinical examination is required to confirm BRD.  相似文献   
16.
白腐菌及黑曲霉对玉米秸秆生物降解的研究   总被引:3,自引:0,他引:3  
利用白腐菌5.776和黑曲霉3.3148对玉米秸秆木质纤维素进行降解,以提高反刍动物对玉米秸秆的消化利用。先对白腐菌和黑曲霉降解玉米秸秆木质纤维素的能力进行了研究,在此基础上,采用正交试验,探索白腐菌和黑曲霉混合后对玉米秸秆的降解效果。结果表明,接种比例、黑曲霉接入时间,接种比例与黑曲霉接入时间的交互作用以及发酵时间对混菌发酵降解玉米秸秆都有显著影响(P<0.05)。最佳方案为:白腐菌液体菌种和黑曲霉孢子悬浮液的接种比例为5:1,白腐菌接种2 d后再接入黑曲霉孢子悬浮液,发酵10 d,所得产物中性洗涤纤维的含量为52.07%,真蛋白为7.89%,干物质损失率为18.75%。  相似文献   
17.
我国黑荆树适生区的划分及各区栽培技术要点   总被引:1,自引:0,他引:1       下载免费PDF全文
Based on the distribution of 64 locations in wattle natural distribution in Australia and the data collected from 61 plantations in 30 more countries, 5 important factors were selected for determining the suitable climatic requirements for the growth of wattle. The experience of plantation wattle in China for over 30 years has been summarized. According to the comparison of climate and geographic distribution of wattle in China and other countries, China is a suitable country for growing wattle. Based on the results of our investigation, a division of suitable areas for growing wattle in China was made. Key points of planting method in each area were suggested.  相似文献   
18.
中国苜蓿审定登记品种叶形态特征及变异分析   总被引:2,自引:0,他引:2  
徐春波  于林清  王勇  萨仁 《草地学报》2007,15(3):243-247,268
利用CI-202型叶面积仪研究29个我国审定登记苜蓿品种(Medicago sativa L.)的叶长、叶宽、叶面积、叶周长、叶长/叶宽和叶形指数。结果表明:地方苜蓿品种和育成品种在叶形态方面存在着较大的差异,前者的叶片较后者小;二者叶片形状相似;在6个指标中,叶长宽比变异最大,叶周长变异最小;地方品种的叶面积、叶长、叶周长和叶长宽比的变异系数均高于育成品种,其他2项指标则低于后者;在育成品种中,中兰1号的变异最大,甘农3号苜蓿最小;在地方品种中,蔚县苜蓿的变异最大,河西苜蓿最小;该结果将为今后培育苜蓿新品种提供理论基础。  相似文献   
19.
OBJECTIVE: To determine the mechanism that enables horses to partially counteract the shift of the center of pressure under the hoof induced by changes in hoof morphology attributable to growth and wear during a shoeing interval. ANIMALS: 18 clinically sound Warmblood horses. PROCEDURES: Horses were evaluated 2 days and 8 weeks after shoeing during trotting on a track containing pressure-force measuring plates and by use of a synchronous infrared gait analysis system set at a frequency of 240 Hz. All feet were trimmed toward straight alignment of the proximal, middle, and distal phalanges and shod with standard flat shoes. Results-Temporal characteristics such as stance time and the time between heel lift and toe off (ie, breakover duration) did not change significantly as a result of shoeing interval. Protraction and retraction angles of the limbs did not change. Compensation was achieved through an increase in the dorsal angle of the metacarpohalangeal or metarsophalangeal (fetlock) joint and a concomitant decrease of the dorsal angle of the hoof wall and fetlock. There was an additional compensatory mechanism in the hind limbs during the landing phase. CONCLUSIONS AND CLINICAL RELEVANCE: Horses compensate for changes in hoof morphology that develop during an 8-week shoeing interval such that they are able to maintain their neuromuscular pattern of movement. The compensation consists of slight alterations in the angles between the distal segments of the limb. Insight into natural compensation mechanisms for hoof imbalance will aid in the understanding and treatment of pathologic conditions in horses.  相似文献   
20.
疫区牛羊同时寄生有捻转血矛线虫、日本血吸虫、伊氏锥虫和肝片吸虫等多种寄生虫。目前血清学诊断方法对这 4种寄生虫病的检测需 2~ 4次操作。将捻转血矛线虫、日本血吸虫、伊氏锥虫和肝片吸虫抗原分别以 0 1 5 ,0 0 4 ,0 0 6和 0 1 3μg/ μL的最佳浓度依次定点在同一硝酸纤维素膜条上 ,制成 4种寄生虫病联合诊断膜。用黄牛IgG ,水牛IgG和山羊IgG联合免疫兔 ,获得了高效价兔抗黄牛、水牛和山羊 (简称兔抗牛羊 )IgG抗血清。应用兔抗牛羊IgG抗血清连接酶标SPA ,建立了 1份血纸能同时用于检测牛、羊捻转血矛线虫、日本血吸虫、伊氏锥虫和肝片吸虫病抗体技术。经浙江、湖北、四川、安徽等省应用 ,该项技术具有省工、省时、经济、实用等优点。适宜于牛、羊捻转血矛线虫、日本血吸虫、伊氏锥虫和肝片吸虫病流行区的普查或监测  相似文献   
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