手掌参多糖提取物对氧化应激舍饲肉羊生产性能、抗氧化机能及肉品质的影响

本试验旨在研究手掌参多糖提取物对氧化应激舍饲肉羊生长性能、肉品质及抗氧化应激作用的影响，为手掌参及其提取物的深入研究与开发提供依据。试验选用20只6月龄体重为（35.0±4.0）kg的健康雄性小尾寒羊，随机分为两组，每组10只羊，分别为试验组和对照组。整个试验期42 d，一共分为3个阶段，前15 d为空白期，中间15 d为处理期，后12 d为造模后观测期。处理期第1天开始，对照组饲喂基础日粮，试验组饲喂在基础日粮内添加30 mg·kg^-1手掌参粗多糖提取物的颗粒饲料。在处理期第15天时，对各组试验羊只按体重（BW）一次性腹腔注射Diquat（敌草快）溶液10 mg·kg^-1，制造氧化应激模型，进入造模后观测期。在整个试验期第1、15、30、33、36、39和42天晨饲前空腹称重并采血，分离血清，测定血清中的抗氧化指标（SOD、GSH-Px、T-AOC、MDA）。在试验期第42天，每组随机选取5只羊屠宰后采集肉样，检测肉品质相关指标。试验结果显示，舍饲肉羊日粮中添加手掌参多糖提取物可显著提高肉羊平均日采食量（P<0.05），且当机体遭受氧化应激时，日粮中添加手掌参多糖提取物的试验处理组平均日采食量、平均日增重以及抗氧化酶含量等指标恢复较快，羊肉滴水损失显著降低，羊肉剪切力显著提高（P<0.05）。试验结果证明，手掌参多糖提取物可提高肉羊生产性能，且能缓解氧化应激造成的生产性能和抗氧化性能下降的问题，具有一定的抗氧化应激作用。     

内蒙古积雪面积时空变化及其对气候响应

区域尺度积雪信息的时空监测,对确定雪灾的影响范围及灾情等级划分具有重要意义。利用2002-2012年10个积雪季节的Terra Aqua/MODIS积雪产品(MOD10A2),按月最大面积合成,分析了内蒙古积雪覆盖面积的时空变化特征及气候响应。结果表明:时间上,近10年内蒙古积雪面积年内变化整体上呈现双峰和单峰的波动特点,最大积雪面积发生在12月和1月份,最小积雪面积发生在10月份。近10年内蒙古积雪面积年际变化呈现波动的特点,整体上积雪面积有减少的趋势。空间上大兴安岭西麓、呼伦贝尔高原以及乌珠穆沁盆地是积雪长时间覆盖区,锡林郭勒草原和乌兰察布草原的积雪面积变化主导着内蒙古的总体积雪面积波动,1月份之前是积雪面积增加的阶段,之后是积雪消融阶段。内蒙古的积雪面积变化与当地的气候条件变化趋势相关,气温的明显上升引起暖冬化,可能导致积雪面积的减少,说明内蒙古积雪面积的变化主要受气温的影响。     

短期碱胁迫条件下燕麦穗组织的蛋白组学解析

盐碱胁迫抑制作物穗的发育与生长,并直接影响作物的产量与品质。为了考查碱胁迫下燕麦穗组织的蛋白组学响应机制,以碱抗性燕麦品种Vao-9和碱敏感品种Xin-17为材料,抽穗期进行短期碱胁迫处理,对其进行蛋白组学分析。结果表明,与对照相比,碱处理后的Vao-9表型稳定,穗组织没有明显变化,而Xin-17的穗生长发育则明显被抑制;Vao-9穗组织中,参与蛋白合成、修复加工过程的蛋白以及参与次生代谢、谷胱甘肽代谢等的酶类显著增加,而Xin-17穗组织中,参与多糖类降解、能量转化的酶类以及PRs类蛋白显著增加。总体上,抗性品种表现为主动防御,而敏感品种表现为被动消耗。     

丹参根腐病拮抗细菌筛选、鉴定及生防机理研究

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。     

昭通黄牛遗传资源调查报告

[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.     

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,观测安普霉素对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。     

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

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.     

Rate of decline of chlorfluazuron concentration in the fat of cattle

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.     

单板层积材在线检测系统硬件抗干扰措施

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     

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

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.