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Medicinal plants have been investigated for their anthelmintic properties and shown to be effective against eggs and larvae of gastrointestinal nematodes. The aim of this study was to evaluate the efficacy of the Lippia sidoides essential oil (LsEO) on sheep gastrointestinal nematodes. Initially, 44 naturally infected sheep were divided and treated with 200 μg kg−1 ivermectin and 230 and 283 mg kg−1 LsEO, respectively, plus the control. Fecal samples were collected from each animal to determine epg at 7, 14 and 21 days after treatment. In another test, 21 sheep were distributed and treated with 200 μg kg−1 ivermectin, 283 mg kg−1 LsEO and the control, respectively. Seven days after treatment, they were euthanized and necropsied to count and identify the nematodes from the abomasum, small and large intestines. In the first test, the efficacy of 230 and 283 mg kg−1 LsEO and ivermectin was 38%, 45.9% and 40.2%, respectively, 7 days after treatment, and 30%, 54% and 39.6%, respectively, 14 days after treatment. In the second experiment, the respective efficacy of 283 mg kg−1 LsEO and ivermectin was 56.9% and 34.4% against Haemonchus spp., and 39.3% and 63.6% against Trichostrongylus spp. 相似文献
104.
两轮多重反转录巢式PCR方法扩增全长GalUR基因 总被引:2,自引:0,他引:2
研究了两轮多重反转录巢式PCR扩增全长基因的方法.先用多重巢式引物和cDNA进行第1轮PCR扩增;再用纯化的第1轮PCR产物和相同的引物进行第2轮扩增;最后通过改变Mg^2+浓度、退火时间和退火温度进行PCR条件的优化,以增加PCR扩增的产量,用于克隆.结果显示该方法方便和快速地扩增出了草莓(Fragaria ananassa cv.SweatCharlie)高产量和高质量的全长GalUR基因,也非常快速地扩增出了用于基因构建的带有酶切位点的全长GalUR基因.该方法也可以用于其它全长基因的克隆. 相似文献
105.
The electrical resistance of wires consisting of either a single xenon atom or two xenon atoms in series was measured and calculated on the basis of an atom-jellium model. Both the measurement and the calculation yielded a resistance of 10(5) ohms for the single-xenon atom system and 10(7) ohms for the two-xenon atom system. These resistances greatly exceeded the 12,900-ohm resistance of an ideal one-dimensional conduction channel because conduction through the xenon atoms occurs through the tail of the xenon 6s resonance, which lies far above the Fermi level. This conduction process in an atom-sized system can now be understood in terms of the electronic states of individual atoms. 相似文献
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ND Sargison 《New Zealand veterinary journal》2020,68(3):136-144
ABSTRACTSmall ruminants are particularly well suited to meet United Nations Sustainable Development Goals surrounding food security, human wellbeing and poverty alleviation in different environmental and climatic settings. However the current efficiency of food production from small ruminants in both developed agricultural regions and in lower and middle income countries is woefully inadequate to meet predicted global needs over the forthcoming decades. Most global research to address this challenge is focussed on the genetics of animal growth, conformation and disease tolerance or resistance traits, albeit the practical consequences of such selection and strategies to use genetically improved animals in the field are uncertain. Any long-term benefits derived from small ruminant genetic selection will only be impactful if steps are first taken to keep animals alive, healthy and productive through iterative planned health management. Parasites are the foremost global infectious disease constraints to efficient small ruminant production. Their genetic adaptability to exploit opportunities afforded by effects of climatic or management changes on free-living stages, or exposure of parasitic stages to drugs, presents specific challenges to their sustainable control. Hence, parasite control provides a relevant means of engagement with livestock keepers and farmers on the topic of planned animal health management. The value of parasitology in this regard is enhanced by the availability of simple to use and accessible diagnostic tools. 相似文献
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Weber HA Hodges AE Guthrie JR O'Brien BM Robaugh D Clark AP Harris RK Algaier JW Smith CS 《Journal of agricultural and food chemistry》2007,55(1):148-156
The major constituents in grape seed and pine bark extracts are proanthocyanidins. To evaluate material available to consumers, select lots were analyzed using high-performance liquid chromatography, gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS), gel permeation chromatography (GPC), and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Atmospheric pressure chemical ionization (APCI) LC/MS was used to identify monomers, dimers, and trimers present. GC/MS analyses led to the identification of ethyl esters of hexadecanoic acid, linoleic acid, and oleic acid, as well as smaller phenolic and terpene components. The GPC molecular weight (MW) distribution indicated components ranging from approximately 162 to approximately 5500 MW (pine bark less than 1180 MW and grape seed approximately 1180 to approximately 5000 MW). MALDI-TOF MS analyses showed that pine bark did not contain oligomers with odd numbers of gallate units and grape seed contained oligomers with both odd and even numbers of gallate. Reflectron MALDI-TOF MS identified oligomers up to a pentamer and heptamer, and linear MALDI-TOF MS showed a mass range nearly double that of reflectron analyses. 相似文献
109.
In the mid-1970s, Mozambique embarked on several forestry projects to promote and establish large plantation areas with eucalypt trees. The planted species included Corymbia citriodora, Eucalyptus camaldulensis, E. saligna and E. tereticornis. Similar to other regions of the world, pests and pathogens pose a significant threat to eucalypt plantations in Mozambique, but little is known regarding the diseases of trees in the country. The aim of this study was to provide the first detailed consideration of the possible disease problems affecting plantation- grown eucalypt species in the central and northern provinces of Mozambique. Isolates of fungal pathogens were obtained from material displaying disease symptoms collected during two field surveys conducted in 2010 and 2011. Representative fungal isolates were identified using DNA sequence data. Stem canker diseases caused by fungi in the Botryosphaeriaceae, Cryphonectriaceae and Teratosphaeriaceae, as well as leaf spots caused by species of Calonectria, Pilidiella, Pilidium and Phakopsora myrtacearum were commonly encountered. Their relative importance to the future of planation forestry in Mozambique is discussed. 相似文献