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1.
利用NIM插件探测器及金硅面垒探头组装了植物活体水分探测仪;筛选并分析了仪器的最佳工作条件;检测了春小麦、玉米、苜蓿、豌豆、红豆草叶片鲜重的变化。结果表明;叶片水分随时间损失大的,其抗旱性差。叶片保水的秩序为:红豆草、豌豆>苜蓿>春小麦>玉米。  相似文献   
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灌溉水源是北方地区耕地后备资源能否有效开发的关键。当前,中国正在推动国家水网工程规划建设,为北方地区耕地后备资源开发提供了新的机遇。在以往研究基础上,该研究考虑北方地区已建、在建及规划的供水工程,基于自然适宜、利用高效、发展稳定三方面评价准则,结合三维魔方空间分类方法,开展了雨养情景和供水灌溉情景下耕地后备资源开发潜力分析。结果表明:雨养农业情景下,北方地区勉强适宜(Ⅱ级)、中度(Ⅲ级)和高度(Ⅳ级)适宜的耕地后备资源面积分别为2.9万、1.0万和0.6万km2。灌溉农业情景下,耕地后备资源面积明显增加,勉强适宜(Ⅱ级)、中度(Ⅲ级)和高度(Ⅳ级)适宜的耕地后备资源面积将分别达到5.4万、7.6万和6.5万km2,主要集中于新疆、内蒙古和甘肃3省(自治区)。该研究结果可为中国耕地后备资源开发利用及国家水网工程效益发挥提供参考。  相似文献   
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Brachiaria decumbens is an extremely productive tropical grass due to its aggressive growth habit and its adaptation to a varied range of soil types and environments. As a result of the vast availability, treated B. decumbens demonstrates as a promising local material that could be utilised as an improved diet for sheep and goats. Despite the fact that the grass significantly increases weight gains in grazing farm animals, there were many reports of general ill-thrift and sporadic outbreaks of photosensitivity in livestock due to the toxic compound of steroidal saponin found in B. decumbens. Ensiling and haymaking were found to be effective in removing toxin and undesirable compounds in the grass. Biological treatments using urea, activated charcoal, polyethylene glycol, and effective microorganisms were found to be useful in anti-nutritional factor deactivation and improving the nutritive values of feedstuffs. Besides, oral administration of phenobarbitone showed some degree of protection in sheep that fed on B. decumbens pasture. In this review, we aim to determine the effect of B. decumbens toxicity and possible treatment methods on the grass to be used as an improved diet for small ruminant.  相似文献   
5.
Papillomaviruses are non-enveloped, DNA viruses that infect skin and mucosa of a wide variety of vertebrates, causing neoplasias or simply persisting asymptomatically. Avian papillomaviruses, with six fully sequenced genomes, are the second most studied group after mammalian papillomaviruses. In this study, we describe the first oral avian papillomavirus, detected in the tongue of a dead Yorkshire canary (Serinus canaria) and in oral swabs of the same bird and other two live canaries from an aviary in Madrid, Spain. Its genome is 8,071 bp and presents the canonical papillomavirus architecture with six early (E6, E7, E1, E9, E2, E4) and two late open reading frames (L1 and L2) and a long control region between L1 and E6. This new avian papillomavirus L1 gene shares a 64% pairwise identity with FcPV1 L1, so it has been classified as a new species (ScPV1) within the Ethapapillomavirus genus. Although the canary died after showing breathing problems, there is no evidence that the papillomavirus caused those symptoms so it could be part of the oral microbiota of the birds. Hence, future investigations are needed to evaluate the clinical relevance of the virus.  相似文献   
6.
Ultrasonography is a valuable tool for the evaluation of neoplastic lesions in the dog and there is a growing interest in the use of this technique for the stadiation of canine mammary tumours. An accurate assessment of small sized nodules facilitates the stadiation of the mammary lesions and helps the clinician in the choice of the most indicated surgical therapy. The aim of this study was to identify those ultrasound criteria that may be useful in discriminating between benign and malignant lesions of small size (diameter smaller than 2 cm). Sixty-two nodules, < 2 cm in larger diameter, belonging to thirty-five bitches presented between January 2012 and February 2014 were evaluated. Tumours were observed by conventional ultrasound and assessed for: shape (regular-irregular), limit (defined-ill-defined), margins (regular-irregular), echogenicity (hypoechoic-isoechoic-hyperecoic), echotexture (homogeneus-heterogeneus), presence of hyperecoic halo, distal acoustic enhancement or shadowing and surrounding tissue alterations. Among the alterations in surrounding tissues, the disruption of the glandular tissue and the increase in echogenicity of the peritumoral tissues were assessed. Thereafter, bitches were subjected to mastectomy and nodules were evaluated histologically. None of the ultasound criteria considered in the current study showed a statistically significant relation with malignancy, except for the presence of alterations in the tissue surrounding the nodules. According to our results, this characteristic may indicate malignancy, however its subjectivity may affect the applicability in clinical practice. In conclusions, conventional ultrasound in bitches had a limited ability in discriminating benign and malignant mammary gland neoplastic lesions of small size (diameter?<?2 cm).  相似文献   
7.
A cross-sectional study was done from March 2013 to May 2014 to assess knowledge, attitudes, and practices towards cystic echinococcosis (CE) or hydatidosis among selected pastoral and agro-pastoral communities in Uganda. A structured questionnaire was administered to 381 respondents. Multivariate logistic regression analysis was done to find the relationship between knowledge about CE and factors such as age, sex, and level of education across all regions. The odds ratio and confidence interval were used to determine the difference in responses across regions. It was shown that age above 36 years was significantly (p < 0.001) associated with awareness about CE in livestock. Likewise, uneducated (p < 0.0001) and agro-pastoralists (p = 0.01) were significantly less knowledgeable than the educated and pastoralists across all regions. The overall knowledge towards CE in livestock was low 17.8% (95% CI = 14.0–21.6). Dog ownership was high and they never dewormed their freely roaming dogs. Dogs shared water with livestock. In conclusion, knowledge about CE in livestock was low across all regions. Therefore, public health education and formulation of policies towards its control by the relevant stakeholders should be done. Also, the true prevalence of CE in livestock needs to be done so that the magnitude and its public health significance are elucidated.  相似文献   
8.
A follow-up study from 2005 to 2010 was carried out in two herds where eradication programme for the bovine herpes virus-1 (BoHV-1) infection depends on the vaccination with inactivated glycoprotein E-deleted vaccine that was started in 2001 following the vaccination with inactivated conventional vaccine between 1999 and 2001. For serological screening, a total of 12,976 sera sampled over several sampling times approximately 6 months of interval during 5 years (2005–2010) were tested for glycoprotein E (gE)- and glycoprotein B-specific antibodies using ELISA. According to the serological evidence, the long-term persistence of BoHV-1 antibodies, success of marker vaccine, first vaccination time of the calves in herds regularly vaccinated, etc. were discussed in this paper. In conclusion, the vaccination programme using gE (?) marker vaccines, with making efforts to prevent the other factors about transmission of infection, was suggested for the eradication of BoHV-1 infection in Turkey as many EU countries. This is the first report on the BoHV-1 eradication programme in some dairy cattle in Turkey.  相似文献   
9.
2017年5月21日,陕西省榆林市某养殖场的蛋鸡出现异常死亡。经国家参考实验室确诊,该起疫情为H7N9流感疫情。为找出引发疫情的可能原因,采用描述性流行病学方法,描述疫情的三间分布,分析发病的风险因素。调查结果显示:该场饲养规模较大,共有8栋鸡舍,饲养4.5万只蛋鸡;疫情暴发突然,病程仅为5 d;蛋鸡死亡2.2万只,死亡率为48.9%;疫情具有明显的场内传播规律,从靠近鸡场入口的鸡舍逐渐向内蔓延;产蛋高峰期蛋鸡的发病风险是雏鸡的37.458倍,差异显著(P0.05);所分离毒株的HA基因裂解位点有4个氨基酸插入,为变异株;该起疫情可能是通过运输淘汰蛋鸡的车辆、野鸟、饲料和饮水,以及调入雏鸡等途径引入的。疫情发生后,当地政府按照《高致病性禽流感防治技术规范》,发布了封锁令,划定了疫点、疫区和受威胁区;在疫区采取了扑杀、无害化处理、关闭疫区内所有禽类产品交易市场等控制措施。采取以上处置措施后,疫情得以快速有效控制。  相似文献   
10.
以草鱼呼肠孤病毒(GCRV)873毒株为试验材料,建立了GCRV荧光定量PCR检测方法;用GCRV873株感染CIK细胞及草鱼,通过对病毒RNA复制水平、子代病毒含量以及细胞病变等情况进行监测,研究其在CIK细胞及草鱼体内的生长特性。在CIK细胞中,GCRV感染后12 h即可检测到子代病毒,36 h时,所有细胞被感染;72 h时,病毒滴度达到最高,为10~(6.75) TCID_(50)/mL。在草鱼的肝、脾、肾中,均能检测到GCRV RNA,其中肾脏中含量最高,其次是肝脏,脾脏中最少。本试验为研究GCRV致病机理及制备细胞灭活疫苗奠定了试验基础。  相似文献   
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