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1.
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   
2.
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   
3.
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   
4.
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   
5.
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   
6.
麦冬是我国传统中药之一,兼备保健和治疗作用。为了探究麦冬能否应用在宠物食品中,本试验以不同浓度的麦冬水提物(3.91 ~8000 μg/mL)为受试药物,从细胞的形态、增殖、凋亡及周期4个方面对猫肾细胞(F81)进行安全性评价。结果表明:在试验浓度范围内,麦冬水提物没有抑制F81的增殖,且在3.91~62.5 μg/mL的浓度范围内,凋亡及周期结果经统计学分析均无显著性差异,与对照组接近,且细胞形态良好。说明在一定浓度范围内,麦冬水提物对F81细胞无毒害作用。  相似文献   
7.
对6个耐热性不同的辣椒品种进行高温处理,计算热害指数,并研究辣椒幼苗叶片中超氧化物歧化酶、过氧化物酶的活性变化,以及丙二醛、脯氨酸的含量变化。结果表明,辛香8号和辛香24号耐热性较强;随着胁迫温度的升高,辣椒叶片中SOD的活性均表现为先上升后下降;POD活性与品种耐热性无明显相关性;MDA含量和脯氨酸含量与胁迫温度呈正相关。SOD活性、PRO和MDA含量变化可以作为辣椒耐热性鉴定的生理指标,而POD活性则不适合用于鉴定辣椒的耐热性。  相似文献   
8.
桃树不同生长型及其研究进展   总被引:7,自引:4,他引:7  
生长型是桃树重要的树体特征,是控制树体大小的遗传因素,与栽培关系密切。综合有关文献介绍了桃树的紧凑型、半矮化型、矮化型、柱型、直立型、短枝型、垂枝型等生长型资源及不同生长型在遗传、形态特征、生理、栽培等方面的研究进展。紧凑型受单位点显性基因控制,树体开张,分枝角度大,萌芽率及成枝力均高,光透过率较低;半矮化型树体介于普通型和紧凑型之间;矮化型为单基因隐性性状,节间极短,树体矮小,叶片密度大,光透过率低;柱型枝条分枝角度小,冠幅小,叶面积指数大;直立型介于柱型和普通型之间;短枝型能形成较多的短果枝,并以短果枝结果为主;垂枝型枝条披散下垂,枝条弯曲。不同生长型之间在氮素、干物质分配和内源激素水平上也存在一定的差异。紧凑型、矮化型由于树冠密度大,光透过率低而在应用上受到限制,直立型和柱型因适应了高密度栽培而更受人们的重视。针对目前存在的生长型分类与命名问题,作者认为应首先考虑节间长度,其次为萌芽率、成枝力等,然后考虑的是枝条的分枝角度。  相似文献   
9.
大肠杆菌主要寄居于人和动物的肠道内,在自然界分布广泛,属于条件致病菌.大肠杆菌能通过消化道使人类和畜禽发生感染和中毒.对大肠杆菌病的防治和流行病学调查都依赖于对病原的及时准确的检测和鉴定.本文对大肠杆菌病各种实验室病原检测方法,包括细菌的分离培养、荧光免疫测定技术、免疫胶体金标记技术、免疫磁珠分离法、多重PCR、荧光定量PCR等方法作以概要性综述.  相似文献   
10.
董凤丽  刘杰  黄河  张蜜  周蕴薇  戴思兰 《草业科学》2014,8(7):1283-1289
基于已建立的甘菊ESTs文库,检索到了CBL基因4个不同的EST序列;采用RACE技术获得了它们的全长序列,并命名为ClCBL1-4。将甘菊(Chrysanthemum lavandulifolium)ClCBL与拟南芥(Arabidopsis thaliana)的CBL进行多重序列比对发现,它们都含有4个结合钙离子的EF-hand结构域,且ClCBL1在N端有一个豆蔻酰化序列(MGCXXSK/T)。采用RT-PCR技术,分析了甘菊中CBL基因的表达与不同逆境胁迫的关系,表明甘菊CBL基因的表达在冷、干旱、热、盐及ABA胁迫中可被不同程度地诱导,而在非逆境胁迫条件下,甘菊CBL基因在根、茎、叶及花等不同器官中均有表达,且表达量相对一致。这些结果说明该家族基因参与了植物非生物逆境胁迫的抵御。  相似文献   
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