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941.
CASE HISTORY An 18-month clinical course of chronic ill-thrift, weight loss and emaciation, and eventual death occurred in a group of 520 translocated elk of mixed age and sex. Trans-location was carried out without regard to animal welfare or health risks associated with the translocation. Mortality was approximately 84% (436/520) despite supportive nutritional and medical treatment. PATHOLOGICAL FINDINGS: General clinical and post-mortem examinations indicated only Se and Cu imbalances and nutritional inadequacy. Additional purposeful post-mortem examination and histological evaluation of tissue sections from four of the affected adult elk demonstrated elevated abomasal pH and proliferative abomasal lesions as the most significant findings, consistent with Type-II ostertagiosis; intra-lesional nematodes were seen in the abomasum of two animals. DIAGNOSIS: Fading elk syndrome, or abomasal parasite syndrome in elk. CLINICAL RELEVANCE: Abomasal parasite syndrome initiated by Type-II ostertagiosis should be considered as a differential diagnosis in cases of ill-thrift and wasting in elk or elk-red deer hybrids. Changes to the architecture and secretory function of the abomasal wall lead to apparently irreversible digestive pathophysiology and nutritional disease. 相似文献
942.
J. G. V. Joubert 《African Journal of Range and Forage Science》2013,30(1):62-68
Uittreksel In die Robertson‐Karoo word agt plantegemeenskappe onderskei. Kwantitatiewe plantopnames is in al die gemeenskappe gemaak. Sukkulente soorte maak vandag ‘n groot deel van die plantgroei uit. Die plantegemeenskappe is baie stabiel na indringing van sukkulente wat dan min of meer permanent dominant bly. ‘n Lae persentasie van die plantgroei word deur diere gevreet. In die somermaande ‘kom min vreetbare materiaal in die veld voor teenoor ‘n groter hoeveelheid in die winter en lente. Vanaf die laat herfs (Mei) tot die einde van die lente (Okrobeir) is die veld kwesbaar teenoor beweiding omdat blaarontwikkeling en blomvorming plaasvind. Suksesvolle vestiging van kunsmatiggesaaide vreetbare Osteospermum sinuatum wek groot verwagting ten opsigte van radikale veldverbetering. 相似文献
943.
A. de Souza R. C. Delphino Carboni E. Wickert E. G. de Macedo Lemos A. de Goes 《Plant pathology》2013,62(5):1038-1047
The aim of the present study was to analyse the genetic and pathogenic variability of Colletotrichum spp. isolates from various organs and cultivars of mango with anthracnose symptoms, collected from different municipalities of São Paulo State, Brazil. Colletotrichum gloeosporioides isolates from symptomless citrus leaves and C. acutatum isolates from citrus flowers with post‐bloom fruit drop symptoms were included as controls. Sequencing of the ITS region allowed the identification of 183 C. gloeosporioides isolates from mango; only one isolate was identified as C. acutatum. amova analysis of ITS sequences showed larger genetic variability among isolates from the same municipality than among those from different populations. fAFLP markers indicated high levels of genetic variability among the C. gloeosporioides isolates from mango and no correlation between genetic variability and isolate source. Only one C. gloeosporioides mango isolate had the same genotype as the C. gloeosporioides isolates from citrus leaves, as determined by ITS sequencing and fAFLP analysis. Pathogenicity tests revealed that C. gloeosporioides and C. acutatum isolates from either mango or citrus can cause anthracnose symptoms on leaves of mango cvs Palmer and Tommy Atkins and blossom blight symptoms in citrus flowers. These outcomes indicate a lack of host specificity of the Colletotrichum species and suggest the possibility of host migration. 相似文献
944.
《Communications in Soil Science and Plant Analysis》2012,43(7):519-529
Abstract ‘Merion’ Kentucky bluegrass (Poa pratensis L.), ‘Pennfine’ perennial ryegrass (Lolium perenne L.), ‘Seaside’ creeping bent‐grass (Agrostis palustris Huds.), ‘Dawson’ slender creeping red fescue (Festuca rubra trichophylla (L.) Gaud.), ‘Fults’ weeping alkaligrass (Puccinellia distans (L.) Parl.), and ‘common’ Lemmon alkaligrass (Puccinellia lemmoni (Vasey) Scribn.) were evaluated for germination and seedling survival in the greenhouse and laboratory under saline conditions. Overall results indicated that weeping and Lemmon alkaligrass were superior performers under saline and/or sodic conditions. Among the remaining four species, none appeared clearly superior in overall performance. 相似文献
945.
刺桐叶部特征与其对刺桐姬小蜂抗性的关系 总被引:2,自引:0,他引:2
依据刺桐不同品系叶片的形态和解剖特征,结合其对刺桐姬小蜂(Quadrastichu erythrinae)的抗性表现,探讨二者的相互关系,对于揭示植食性昆虫与寄主植物的相互关系,选育抗虫刺桐品系并推广种植具有重要意义。研究结果表明:刺桐高感品系的叶片形状、厚度与高抗和中抗品系存在显著差异,可作为抗性鉴定的依据之一。从叶表微观形态来看,高抗品系上表皮不存在气孔器,上、下表皮的表皮细胞形状、大小均匀一致,排列致密,细胞间隙很小,表面密被霜状蜡质层保护,不利于刺桐姬小蜂侵入和产卵的构造;从叶片横切面结构上看,高感刺桐品系的栅栏组织、海绵组织、维管束鞘、上下表皮显著薄于高抗品系,且各内部组织细胞体积较大、排列疏松,不能有效抵御刺桐姬小蜂侵入与危害。同时,刺桐东方变种(Erythrina variegate var orientalis)HA1是高感品系,应禁止调运和引种;本地刺桐(E. variegate)HA2具有很强的抗虫性,宜于推广种植。 相似文献
946.
We evaluated production performance, fillet composition, and sensory integrity of sunshine bass (Morone chrysops x M. saxatilis) fed a marine oil-based finishing feed after being raised on a plant oil-based production feed. Two feeds containing either corn oil (CO) or menhaden oil (MO) were fed to sunshine bass according to different feeding regimens at the close of the production cycle: control groups were fed the CO or the MO feeds exclusively; remaining groups were transitioned from the CO feed to the MO feed at 4-, 8- or 12-week intervals. Replacing MO with CO yielded fillets with distinctly different fatty acid profiles; however, finishing with an MO-based feed for 4–8 weeks offered significant compensation for reductions in fillet nutritional quality. Production performance and fillet sensory characteristics were largely unaffected by dietary lipid source, suggesting fillet fatty acid profile can be manipulated to maximize nutritional value of cultured fillets without reducing consumer acceptance. 相似文献
947.
948.
鉴于抗生素在饲料添加剂中的滥用,研究高效复合益生菌来替代抗生素已变得越来越重要。益生菌是一类新型饲料(食品)添加剂,可改善人畜肠道环境,减少体内有害菌群及有害物质含量。在本实验中,利用大肠杆菌(Escherichia coli)为抑菌对象,分离到4株益生菌,实验证明其抑菌效果理想,经过经形态学观察及传统生理生化实验分析表明:本实验所获得的4株菌均为芽孢杆菌(Bacillus spp.),为进一步开发高效复合益生菌奠定菌种基础。 相似文献
949.
东莞大蕉超表达拟南芥CBF1基因及其抗寒性检测 总被引:2,自引:1,他引:1
【目的】研究超表达拟南芥CBF1基因(AtCBF1)对大蕉抗寒性的影响,为从大蕉克隆抗寒相关基因奠定基础。【方法】采用农杆菌介导法转化东莞大蕉的胚性细胞悬浮系,获得转AtCBF1基因的大蕉植株;利用GUS组织染色、PCR、RT-PCR以及RT-qPCR对转基因植株进行鉴定;比较低温处理后的转基因株系和对照的冷害特征以及超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量等生理生化指标,鉴定转基因大蕉植株的抗寒能力。【结果】试验共获得6个抗性再生转化系。GUS组织染色结果表明,除T1外,其余均为阳性;PCR鉴定结果表明,AtCBF1在6个抗性再生转化系均为阳性,而GUS基因在T1转化系中没有检测出;RT-PCR结果表明,AtCBF1在6个转化系均得到表达,对T1、T2和T3 3个转化系进行RT-qPCR检测发现,AtCBF1基因在3个转基因株系表达水平存在差异;在低温处理下,转基因植株的叶片相对电导率、MDA的累积都低于非转基因植株,而SOD总活性高于对照;低温处理条件下,转基因植株叶片的冷害症状明显轻于对照。【结论】AtCBF1在大蕉中超表达,具有增强大蕉SOD活性,降低因低温导致的MDA含量和离子渗漏率,缓解质膜过氧程度,进而改善大蕉植株抗低温胁迫的能力。 相似文献
950.
T. Kapari-Isaia A. Kyriakou L. Papayiannis D. Tsaltas S. Gregoriou I. Psaltis 《Plant pathology》2008,57(2):348-353
A new laboratory technique combining shoot-tip grafting in vitro and biological indexing on indicator plants was explored for the detection of citrus exocortis and related viroids. Τhree in vitro laboratory methods were used and compared with the classical biological method. With the classical in vivo method, diagnosis is based on the expression of symptoms on indicators 11–14 weeks after inoculation. In contrast, with the first in vitro method, microindexing in vitro of citron seedlings by graft inoculation, diagnosis was possible 12 days after inoculation; with the second method, microindexing in vitro of citron cuttings by graft inoculation, 20 days after inoculation; and with the third method, microindexing in vitro of citron cuttings by injection inoculation, 40 days after inoculation. Inoculated Etrog citron plantlets grown in vitro and tested by RT-PCR showed the same viroid content as the source plants. Of the three in vitro viroid indexing methods, microindexing on cuttings by grafting was easier and more reliable than microindexing either on seedlings or on cuttings by injection. 相似文献