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

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.     

青海省黄南州泽库、河南两县畜牧生产调查报告

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。     

Production responses to internal parasite control in dairy cattle

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.     

日光温室杏果实发育规律研究

对日光温室与露地栽培的金太阳杏果实生长发育规律进行了观察与分析。结果表明,日光温室栽培可使杏果实发育的第一速生期、第二速生期延长,果实发育的缓慢生长期缩短,整个生育期较露地栽培延长了15d;日光温室内金太阳杏第一速生期的生长速率显著低于露地,第二速生期的累积生长量显著高于露地;较低的夜间温度是造成温室内杏果实第一速生期较长、生长较慢以及果实个体较大的原因;日光温室内金太阳杏果实的横径、纵径与鲜果质量之间存在明显的乘幂回归关系(r=0.98**,r=0.99**);日光温室内金太阳杏鲜果质量与发育时间之间的关系符合Log istic生长曲线(r=-0.99**)。     

马铃薯叶片气孔的开张与关闭同步伴随果胶的降解与合成

【目的】 比较气孔关闭与不同气孔密度开张之间叶片分化表达蛋白质及其积累变化,揭示果胶代谢如何调控气孔开张和关闭,为深入理解气孔的环境适应功能提供依据。【方法】 构建体内过量和抑制StEPF-2（EPIDERMAL PATTERNING FACTOR 2 from Solanum tuberosum）表达载体,以茎段为外植体,转化马铃薯克新1号植株,获得不同气孔密度的转化株系,以黑暗条件下气孔关闭为对照,采用RNA-seq和iTRAQ分别检测不同处理和对照叶片的基因和蛋白质表达谱,比较不同气孔密度分化表达的蛋白质,并通过StEPF-2标记的pulldown和LC-MS/MS结果确认,明确不同气孔密度特异诱导表达的胞壁果胶代谢参与的蛋白质。【结果】 叶片成熟过程中,随着气孔的关闭和开张,至少有14个蛋白质家族参与了保卫细胞壁果胶的代谢;黑暗条件下,气孔关闭时有5个蛋白质家族特异表达,分别是阻止HGs水解的多聚半乳糖醛酸酶抑制子（polygalacturonase inhibitor,PGI）、RG侧链合成的UDP-鼠李糖合成酶（rhamnose synthase,RHM）、半乳聚糖β-1,4半乳糖基转移酶（galactan β-1,4-galactosyltransferase,GALS）、UDP-D-葡萄糖醛-4-异构酶（UDP-D-glucuronate 4-epimerase,GAE）和聚半乳糖4-α-半乳糖转移酶（polygalacturonate 4-α-galacturonosyltransferase,GAUT）;光照条件下,在不同气孔密度的叶片中检出4个蛋白质家族特异表达,它们分别是降解果胶C6甲酯的果胶甲基酯酶（pectinmethylesterase,PME）、内切和末端水解果胶的多聚半乳糖醛酸酶（polygalacturonase,PG）、α-半乳糖苷酶（α-galactosidase,AGAL）和类果胶裂解酶（pectate lyase-like,PLL）。另有5个蛋白质家族同时参与了气孔的开张和关闭,它们分别是阿拉伯半乳聚糖-蛋白质（aabinogalactan-protein,AGP）、果胶乙酰酯酶（pectinacetylesterase,PAE）、β-半乳糖苷酶（β-galactosidase,BGAL）、类枯草杆菌蛋白酶（subtilase-like,SBT）和果胶甲基酯酶抑制子（pectinesterase inhibitor,PMEI）。【结论】 光照条件下,PME催化果胶去甲酯,其后PG和PLL及AGAL分别内切和末端水解果胶,丧失结构的果胶在膨压下开裂,打开气孔;黑暗条件下,PGIP抑制果胶水解,RHM增强果胶侧链合成,结构完整的果胶自行膨胀,保持气孔关闭。     

遥控自动立木整枝机运动控制系统

正确的控制逻辑是自动立木整枝机运动控制系统的关键技术.该文根据作业要求,研制了基于复杂可编程逻辑器件的自动立木整枝机运动控制系统.该系统采用自制的新型电动机位置动态检测装置,通过复杂数字逻辑运算及相应的闭环控制驱动电路,实现对人工林自动立木整枝机控制信号的分组、实时控制.该运动控制系统设计合理、控制逻辑准确,已成功应用于BSR Z23 001A人工林自动立木整枝机,工作可靠,使用效果良好.      

Ultraviolet B radiation-mediated stress ethylene emission from rice plants is regulated by 1-aminocyclopropane-1-carboxylate deaminase-producing bacteria

Dear Editor,Industrial emissions have played a major role in damaging the ozone layer,leading to increased atmospheric penetration of ultraviolet B (UV-B)(290–320 nm) radiation (Jordan,2002).The recovery rate of the damaged ozone layer in the mid-latitudes and tropics has been insignificant since 1979(Chipperfield et al.,2017),even after the adoption of the Montreal Protocol (Protocol,1987),and the recovery process is expected to take many decades.In the meantime,UV-B radiation continues to penetrate the atmosphere (McKenzie et al.,2011;Bais et al.,2019).The characteristic short length and high energy of this radiation wavelength can directly affect major molecules,such as DNA,proteins,and lipids,which are important to living beings (Hideg et al.,2013).Rice is one of the major global crops,which is generally cultivated at lower latitudes and can potentially be exposed to a higher flux of UV radiation due to greater solar angles and longer duration of sunlight (Kataria and Guruprasad,2012).     

短期氮添加对荒漠草原土壤微生物特征的影响

为探究荒漠草原土壤微生物特征对短期氮添加的响应,以宁夏荒漠草原为对象,参照国内外同类研究和当地的氮沉降量,设置N0、N1、N2、N3、N4的5个处理,其纯氮添加量分别为0,2.5,5,10,15 g/(m²·a),以尿素为氮源进行为期2年的氮添加试验,对不同氮添加处理下荒漠草原浅层土壤微生物特征进行了研究。结果表明:(1)随氮添加量的增加,荒漠草原0—20 cm土层土壤铵态氮含量呈升高的变化趋势,硝态氮含量呈先升高后下降的变化趋势。在0—10 cm土层,N1、N2、N3、N4处理草地铵态氮含量较N0处理分别增加了109.61％,136.52％,197.19％,198.88％,硝态氮含量以N2处理草地最高,显著高于N0、N3、N4处理(P<0.05)。(2)与N0相比,施氮后0—10 cm土层土壤微生物量氮含量显著下降,N1、N2、N3和N4处理分别较N0处理降低了37.54％,38.11％,28.56％,29.81％。(3)随氮添加量的增加,荒漠草原0—10 cm土层土壤真菌数量呈逐渐减少的变化趋势,N0、N1处理草地显著大于N3、N4处理草地(P＜0.05)。PcoA分析显示高氮添加处理(N3、N4)对荒漠草原土壤amoA区、nirK区微生物的群落结构有显著改变。高氮添加(N3、N4)会对荒漠草原土壤微生物群落产生负面影响,具体表现为真菌数量减少,硝态氮含量降低,氮转化微生物的α多样性和优势菌丰度降低,群落结构发生显著改变。     

安普霉素对仔猪养分代谢率及氮沉积的影响

20头28日龄大长北三元杂交断奶仔公猪随机分为4组，分别饲养于不同环境温度（28℃、15℃）下的代谢笼内，饲喂含有不同剂量安普霉素（0、90、150mg／kg）的日粮．试验期为2周．后7d进行全收粪代谢试验，观测安普霉素时仔猪物质表观代谢率及氮沉积的影响。研究结果表明，在低温环境下日粮中添加安普霉素可抵御寒冷应激，改善仔猪日粮干物质和蛋白质的表观代谢率，增加机体氮的沉积，其中150mg／kg安普霉素可显著提高仔猪日增重70．5％（P〈0．05）、改善饲料转化率32．7％（P〈0．05），并能提高采食量、降低发病死亡率。在低温环境下，应适当加大抗生素的添加剂量。