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101.
西藏不同青稞品种的品质差异分析   总被引:2,自引:0,他引:2  
为了解西藏地区不同青稞品种的品质差异,采集了西藏青稞主产区的不同青稞品种,并对青稞中的水分、淀粉、粗蛋白、粗纤维、矿质元素以及有效成分总黄酮、花青素、β-葡聚糖等14项指标进行了检测。结果表明:有色青稞中淀粉和微量元素Mn、Cu、Zn的含量在年度间存在着显著的差异,且有色青稞微量元素含量普遍偏低;青稞总黄酮含量范围在0.14%~0.42%,均值为0.23%;β-葡聚糖含量范围为2.65%~6.52%,均值为4.59%;有色青稞花青素含量变化较大,范围在0.022 7~0.649 7 mg/g,均值为0.133 2 mg/g。总黄酮含量、β-葡聚糖含量年际间差异不大,花青素含量年际间差异巨大。总黄酮含量有色青稞显著高于普通青稞,而β-葡聚糖含量二者无显著差异。  相似文献   
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临夏州马铃薯种植区域主要分布在无灌溉条件,年降雨量不足200 mm的干旱山地和年降雨量约600 mm的山二阴地,以及灌溉便利,年降雨量在500 mm左右的川塬区。通过种植区域、播种时间和栽培措施3因素对比试验,以产量、病害损失和经济效益做综合分析对比,得出临夏州春旱较频繁的干旱山地和山二阴地区应适当推迟播期至5月上旬左...  相似文献   
105.
The blood physiological and biological indexes were determined in both polled and horned yaks, to investigate the differences of body condition and metabolism between the two breeds, and provide a comprehensive understanding for new yak breeds. Thirty physiological and biochemical indexes of the polled and horned yaks were measured, and all these data were analyzed by independent-samples t test to compare the same index between the two groups. The results showed that there were extremely significant differences (P<0.01) in 11 indexes,5 indexes reached significant differences (P<0.05) and no significant differences (P>0.05) in 14 indexes between the polled and horned yaks. The results suggested that the polled yak was easier to adapt to the plateau hypoxia and there were many differences in adaptability of plateau hypoxia, kidney metabolism, liver metabolism and the growth and development of the bone between the polled and horned yak. This study could provide scientific basis for better protection and utilization of yak and the selection of the new yak breeds.  相似文献   
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Bacteroides nodosus involved in several outbreaks of ovine footrot over a number of years were subjected to DNA restriction endonuclease analysis. Individual isolates were found to have characteristic Bam HI profiles which permitted their accurate identification and differentiation from other isolates. Bam HI profiles of B. nodosus isolates were used in epidemiological investigations involving consecutive outbreaks of footrot on individual and neighbouring farms. The relationship of given isolates to a common source could be established by this means. Restriction endonuclease analysis provides an additional epidemiological tool in ovine footrot investigations as it accurately identifies interstrain differences in a manner not possible by conventional bacteriological and serological means.  相似文献   
108.
Objective: A large‐scale capture method was developed to enable sterilisation of a macropod population in western Sydney from 2005 to 2018. Methods: Until March 2007, free ranging eastern grey kangaroos and red kangaroos were herded into purpose‐built 15 m diameter capture yards (CYs) for darting with a projectile syringe. From March 2007 onwards, animals were free‐range darted in large areas without herding. Kangaroos were darted with 1.33–5.10 mg/kg tiletamine/zolazepam and 0.01–0.02 mg/kg medetomidine, ± 0.03 mg/kg acepromazine. Deaths were monitored. Population counts were performed annually. Results: There were 5825 capture events involving 3963 kangaroos. Over 85% of all captures occurred from 2005 to 2008. Of all reported deaths (n = 523), 135 were attributed to ill health. Musculoskeletal injuries incurred during capture were the main project‐related cause of death (n = 116). Post capture myopathy was uncommonly diagnosed following capture (n = 19). Conclusion: The herding and capture method enabled a large number of kangaroos to be mobilised and captured with low mortality rates, and the use of CYs resulted in fewer capture‐related injuries and deaths than free‐range capture. The drug doses and combinations used for darting were safe and effective, and the capture technique was successfully applied to a population management project.  相似文献   
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The objectives of this study were to determine (i) if in subtropical goats that gave birth during mid‐December, the exposition to an artificial long‐day photoperiod consisting in only 14 hr of light per day can increase the milk yield and (ii) to test whether these females can respond to the male effect at the end of the prolonged photoperiodic treatment. In experiment 1, 17 lactating goats were maintained under natural short days (control group), while another 22 goats were maintained under artificial long days (treated group) consisting in 14 hr light and 10 hr darkness starting at day 10 of lactation. The continuous exposition to an artificial long‐day photoperiod produced an increase in the milk yield level during the first 110 days of lactation (time × treatment interaction; = .01), while none of the milk components were modified due to the photoperiodic treatment (> .05). In experiment 2, all control and treated anovulatory goats were submitted to the male effect using photostimulated males. All females showed oestrous behaviour within the first 10 days that were in contact with males (100% in both groups; > .05). Thus, the latency to onset of oestrus did not differ between females from control (58.2 ± 3.0 hr) and treated (62 ± 4.6 hr) groups. Male exposition provoked ovulation independently if females were previously under long days or natural photoperiod (96 vs 100%, respectively; = .79). It was concluded that exposure to 14 hr of light per day in subtropical goats that gave birth in late autumn stimulates milk yield without preventing the ovulation in response to the male effect at the end of the prolonged photoperiodic treatment.  相似文献   
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