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101.
Reducing methane emissions and the methanogen population in the rumen of Tibetan sheep by dietary supplementation with coconut oil 总被引:1,自引:0,他引:1
Ding X Long R Zhang Q Huang X Guo X Mi J 《Tropical animal health and production》2012,44(7):1541-1545
The objective was to evaluate the effect of dietary coconut oil on methane (CH(4)) emissions and the microbial community in Tibetan sheep. Twelve animals were assigned to receive either a control diet (oaten hay) or a mixture diet containing concentrate (maize meal), in which coconut oil was supplemented at 12?g/day or not for a period of 4?weeks. CH(4) emissions were measured by using the 'tunnel' technique, and microbial communities were examined using quantitative real-time PCR. Daily CH(4) production for the control and forage-to-concentrate ratio of 6:4 was 17.8 and 15.3?g, respectively. Coconut oil was particularly effective at reducing CH(4) emissions from Tibetan sheep. The inclusion of coconut oil for the control decreased CH(4) production (in grams per day) by 61.2%. In addition, there was a positive correlation between the number of methanogens and the daily CH(4) production (R?=?0.95, P?0.001). Oaten hay diet containing maize meal (6:4) plus coconut oil supplemented at 12?g/day decreases the number of methanogens by 77% and a decreases in the ruminal fungal population (85-95%) and Fibrobacter succinogenes (50-98%) but an increase in Ruminococcus flavefaciens (25-70%). The results from our experiment suggest that adding coconut oil to the diet can reduce CH(4) emissions in Tibetan sheep and that these reductions persist for at least the 4-week feeding period. 相似文献
102.
103.
Mi Young Kang Jung Eun Moon Sang Chul Lee 《Journal of Crop Science and Biotechnology》2013,16(2):167-171
The effects of the functional rice cultivars giant embryo and Aranghyangchal on the body weight and lipid metabolism in male C57BL/6N mice under high fat diet conditions were investigated. The animals were randomly placed into four dietary groups: normal control (NC group), high fat (HF group), and high fat supplemented with giant embryo (HF-GE group) or Aranghyangchal (HF-AR group). After 8weeks, a marked increase in the body weight and plasma triglyceride and total cholesterol concentrations were found in the HF mice relative to the control group. However, the addition of the functional rice samples in the high fat diet reduced the body weight gain and significantly decreased the lipid levels through inhibition of lipogenesis and regulation of adipokine production. The results demonstrate that the functional rice grains giant embryo and Aranghyangchal may both be useful as biomaterials in the development of functional food with therapeutic potential against high fat diet-induced hyperlipidemia. 相似文献
104.
The purpose of this study was to investigate the effects of bending properties and drapability on the hand and appearance of wool-blended fabrics for comparison of real clothing with online and 3D virtual garments. Objective evaluations were performed by measuring mechanical properties of fabrics, while subjective evaluations were performed by subjects evaluating sensory images of fabrics; real clothing evaluations were performed offline and online, and 3D virtual garments were evaluated. Bending properties and drape coefficients of fabrics were affected by wool blending ratio, and fabrics with high wool blending ratio showed low stiffness, warm-cool, weight, and high smoothness, drapability image. In the real clothing evaluation, stiffness image showed many differences with online evaluation with respect to wool blending ratio. Objective bending properties and drape coefficients showed no correlation with subjective sensory images offline. For the online results, objective mechanical properties had good correlations with all sensory images except smoothness. Stiffness and warm-cool online scores were higher than the offline ones and the offline drapability was higher than the online one for 100 % wool fabrics. Thus, clothing was generally evaluated online as more hard and moist than real clothing. For the virtual garment evaluation, sensory images had no difference according to wool blending ratio compared with real clothing. Many differences in subjective sensory images between real clothing and virtual garments were observed, except for smoothness and weight images. The results showed that it is difficult to exactly predict the hand and appearance of clothing according to fabric properties using 3D virtual garment system. 相似文献
105.
Hao Jia Wei Chen Xiaoping Yu Xiuhua Wu Shuai Li Hong Liu Jiru Liao Weihua Liu Mantian Mi Longjian Liu Daomei Cheng 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(3):345-353
The effects of black rice anthocyanidins (BRACs) on retinal damage induced by photochemical stress are not well known. In the present study, Sprague-Dawley rats were fed AIN-93M for 1 week, after which 80 rats were randomly divided into two groups and treated with (n = 40) or without BRACs (n = 40) for 15 days, respectively. After treatment, both groups were exposed to fluorescent light (3,000 ± 200 lux; 25℃), and the protective effect of dietary BRACs were evaluated afterwards. Our results showed that dietary BRACs effectively prevented retinal photochemical damage and inhibited the retinal cells apoptosis induced by fluorescent light (p < 0.05). Moreover, dietary BRACs inhibited expression of AP-1 (c-fos/c-jun subunits), up-regulated NF-κB (p65) expression and phosphorylation of IκB-α, and decreased Caspase-1 expression (p < 0.05). These results suggest that BRACs improve retinal damage produced by photochemical stress in rats via AP-1/NF-κB/Caspase-1 apoptotic mechanisms. 相似文献
106.
S. Miño J. Matthijnssens A. Badaracco L. Garaicoechea M. Zeller E. Heylen M. Van Ranst M. Barrandeguy V. Parreño 《Veterinary microbiology》2013,161(3-4):239-246
Equine group A rotavirus (RVA) strains are the most important cause of gastroenteritis in equine neonates and foals worldwide, and G3P[12] and G14P[12] are epidemiologically the most important genotypes. The genotype constellation of an unusual Argentinean G3P[3] RVA strain (RVA/Horse-wt/E3198/2008/G3P[3]) detected in fecal samples of a diarrheic foal in 2008 was shown to be G3–P[3]–I3–R3–C3–M3–A9–N3–T3–E3–H6. Each of these genotypes has been found typically in feline and canine RVA strains, and the genotype constellation is reminiscent to those of Cat97-like RVA strains. However, the phylogenetic analyses revealed only a distant relationship between E3198 and known feline, canine and feline/canine-like human RVA strains. Surprisingly, a rather close relationship was found between E3198 and simian RVA strains RVA/Simian-tc/USA/RRV/1975/G3P[3] for at least 5 gene segments. RRV is believed to be a reassortant between a bovine-like RVA strain and a RVA strains distantly related to feline/canine RVA strains. These analyses indicate that E3198 is unlikely to be of equine origin, and most likely represents a RVA interspecies transmitted virus, possibly in combination with one or more reassortments, from a feline, canine or related host species to a horse. Further studies are in progress to evaluate if this strain was a single interspecies transmission event, or if this strain started to circulate in the equine population. 相似文献
107.
准噶尔盆地硬蜱区系考察与名录记述 总被引:1,自引:0,他引:1
蜱类与人类疾病关系密切,可以携带和传播多种重要病原.准噶尔盆地是我国第二大盆地,地处新疆北部,是我国虫媒疫病的自然疫源地.2010年~2012年期间,通过对新疆准噶尔盆地硬蜱区系考察与分类研究,共采获硬蜱标本19466枚,隶属5属21种,以草原幸蜱(Dermacentor nuttalli Olenev)、亚洲璃眼埤(Hyalomma asiaticum asiaticum Schulze)和银盾车蜱(Dermacentor niveus Neumann)为优势种类,分别占总蜱数的27.76%、23.39%、19.96%.该考察结果填补了近十几年来准噶尔盆地蜱类缺乏系统考察的空缺,考察名录代表了噶尔盆地最新蜱类物种. 相似文献
108.
[目的]分析缅甸农业科技发展及中缅农业科技合作现状并提出建议,为探寻两国农业科技合作开展途径提供理论参考.[方法]采用调查分析、比较研究和文献研究等方法分析缅甸农业科技发展现状,明确优势及薄弱环节;分析中缅农业科技合作现状;根据缅甸农业发展特点及中缅科技合作存在问题提出针对性意见和建议.[结果]缅甸农业资源禀赋优越,但农业科技发展滞后,具有多方面的技术需求,包括作物生产技术、畜禽和水产养殖技术及其配套设施、农产品加工技术、农业机械研发技术等.目前中缅两国农业科技合作基础良好,并逐步建立副部级、国家级农业合作机制,但仍存在农业科技资金投入少、合作规模小、抗风险能力弱及人力资源瓶颈难以突破的问题.[建议]针对缅甸农业科技发展现状,在农产品加工、动植物引种改良及病害防治、肥料应用、耕地开发等领域深化援助合作路径;充分运用我国海外园区建设经验,推进农业科技产业园区合作;进一步调动地缘优势省区农业高校资源优势,支持缅甸农业教育发展. 相似文献
109.
Qin Zhang Guangyu Wang Feng Mi Xuanchang Zhang Lianzhen Xu Yufang Zhang Xiaoli Jiang 《林业研究》2019,(5):1651-1666
Continuously growing populations and rapid economic development have led to the excessive use of forest resources,and the forest ecosystem is threatened.In response,forest ecological security(FES)has attracted attention.In this study,an integrated dynamic simulation model was constructed using the system dynamic method,and it was used to evaluate the FES in China from 1999 to 2014.A scenario analysis was then used to evaluate the changes in the FES under five forestry policy scenarios for the 2015–2050 period,including the baseline,afforestation policy,harvesting policies,management policy,investment policy,and a policy mix.The results showed that the evaluation values of the FES increased during the period from 1999 to 2002,the period from 2004 to 2010 and the year 2014,and they decreased in 2003 and during the period from 2011 to 2013.During the 2015–2050 simulation period,the FES improved continuously.In particular,China would enter a new stage when the economic systems,social systems and ecosystems were in harmony after 2040.To improve the FES and the current status of the FES,a scenario analysis showed the most suitable scenario to be Scenario 5 from 2015 to 2020 and Scenario 2 from 2021 to 2050.To relieve pressure,the most suitable scenario would be Scenario 5 from 2015 to 2040 and from 2046 to 2050,and the most suitable scenario would be Scenario 4 for 2041–2045.A policy mix(Scenario 5)would be most efficient under current conditions,while the effects of all the benefits of the forestry policies would weaken over the long term.The integrated method can be regarded as a decision support tool to help policy makers understand FES and promulgate a reasonable forestry policy. 相似文献
110.