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91.
92.
饲用小黑麦在海河平原区的生产性能及适应性评价 总被引:3,自引:0,他引:3
在海河平原区对11个饲用小黑麦品种进行了生产性能比较试验以及旱作条件下适应性,试验得出:冀饲-1成熟早,生育期短,抽穗期比对照中新830提前6d,干草产量高,比对照中新830提高26.7%,能与春播作物形成一年两作,适于在海河平原区推广利用;冀饲-2在海河平原地区鲜干草产量均较高,分别比对照中新830增产4 854.3kg/hm2和777.0kg/hm2,属于高产品种,茎叶比低,叶量丰富是海河平原区主要品种推广种植。旱作条件下种植,饲用小黑麦株高比正常管理条件下降低64.6%~83.4%,分蘖数和成穗数分别减少60.0%~74.7%和85.3%~98.1%,鲜干草产量分别降低69.3%和70.2%,利用价值不大,只有在一定的灌溉和施肥条件下种植才能产生较好经济效益。 相似文献
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DENG Hua LI Hui YANG Hong ZHOU Zhaohai LIANG Haozhao XU Zhigao WU Fuda LI Qiaofeng HUANG Luqi 《畜牧兽医学报》1956,51(11):2836-2848
To study the clinicopathology and histopathology of African swine fever (ASF), and to explore the internal relationship between pathological changes and disease occurrence and development and its pathological mechanism, 13 Landrace pigs with bodyweight about 20 kg were intramuscular injected with African swine fever virus (ASFV), strain Pig/HLJ/18 at a dose of 102HAD50·mL-1. During the experiment, all the dead pigs were systematically dissected and sampled, paraffin sections were produced, and haematoxylin-eosin staining was performed. Clinicopathological evaluation standards for acute ASF were established, then pathological lesions (classification variables) were expressed by counting frequency and percentage, and the lesion degree (continuous variables) was graded and scored according to different pathological changes of various tissues and organs. The results showed that all infected pigs were in line with the clinical characteristics of ASF, including acute, febrile and highly infectious, with a 100% incidence rate and 100% mortality. The dead pigs showed typical characteristics of septicemia, cadavers prone to corruption, blood clotting adverse or hemolysis, rigor mortis incomplete. The main pathological lesions were hemorrhagic necrotizing lymphadenitis, acute inflammatory splenomegaly (septic spleen), cerebral edema, pulmonary edema and lung consolidation et al. The spleen and lymphonodus are the target organs attacked by ASFV, with the most significant lesions, the earliest occurrence time, the longest duration and the highest frequency. The most prominent pathological changes are blood circulation disorders, including multiple pathological manifestations such as edema, hyperemia, congestion, hemorrhage, infarction, disseminated intravascular coagulation (DIC), and the most important characteristics are hemorrhagic lesions. The inflammatory reaction of lymphocytic exudation caused by ASFV runs through the whole process, especially in the middle and later stages of the course. The results suggest that the main pathological process of acute African swine fever is a typical immune/inflammatory cascade reaction and severe systemic blood circulation disorder, which resulted in the high incidence rate and high mortality rate of acute ASF. 相似文献
96.
本文以不同水平人工草地绵羊放牧系统的监测分析资料为基础,针对原系统中存在的问题,提出了系统优化方案。 相似文献
97.
重组M蛋白间接ELISA检测猪繁殖与呼吸综合征病毒抗体 总被引:2,自引:0,他引:2
用纯化的猪繁殖与呼吸综合征病毒重组M蛋白作包被抗原,建立了检测猪繁殖与呼吸综合征病毒抗体的间接ELISA方法,并确立了ELISA最佳工作条件:抗原包被浓度为3.5μg/mL,37℃1h加4℃过夜,血清(1:40)和酶标SPA(1:80)分别在37℃温育1h,加底物溶液常温显色5min。经重复性试验、交叉试验、阻断试验等试验结果表明该方法重复性好、特异性强、敏感度高;与美国IDEXX公司试剂盒相比较,特异性和敏感性分别为96.3%和93.5%,无显著性差异。用建立的方法检测临床血清样品168份,总阳性率为39.9%。 相似文献
98.
Muhammad MUSHTAQ Iftikhar HUSSAIN Afsar MIAN Shahid MUNIR Irfan AHMED Abdul Aziz KHAN 《Integrative zoology》2013,8(3):285-292
This research study evaluated the effect of different additives on the bait consumption by Indian crested porcupine, a serious forest and agricultural pest, under field conditions. Different additives (saccharin, common salt, bone meal, fish meal, peanut butter, egg yolk, egg shell powder, yeast powder, mineral oil and coconut oil) at 2 and 5% each were tested for their relative preference, using groundnut–maize (1:1) as basic bait. All the additives were tested under a no‐choice test pattern. For control tests, no additive was mixed with the basic bait. Saccharin at 5% concentration significantly enhanced the consumption of bait over the basic bait, while 2% saccharin supplemented bait resulted in a non‐significant bait consumption. All other additives did not enhance the consumption of the bait material; rather, these worked as repellents. However, the repellency was lowest with the common salt, followed by egg yolk, egg shell powder, bone meal, peanut butter, mineral oil, fish meal and yeast powder, while coconut remained the most repellent compound. The present study suggested that groundnut–maize (1:1) supplemented with 5% saccharin was the preferred bait combination, and can be used with different rodenticides for the management of Indian crested porcupine. 相似文献
99.
狂犬病病毒BD-06株基质蛋白的原核表达、纯化及其多克隆抗体的制备 总被引:2,自引:0,他引:2
本研究旨在获得抗狂犬病病毒M蛋白的多克隆抗体,为进一步研究M蛋白功能提供材料。本试验以狂犬病病毒BD06毒株为模板克隆M基因序列,将其克隆至原核表达载体pET28a;经酶切和测序鉴定,M蛋白基因序列已正确插入表达载体pET28a;以表达载体pET28a-M转化E.coli Rosetta株,并以0.5 mmol/L IPTG诱导,结果表达出27 ku左右的M蛋白;将诱导表达的蛋白质回收纯化,以纯化的M蛋白多次免疫兔子制备多克隆抗体;Western blotting分析和间接免疫荧光分析结果表明,制得的抗体与病毒能够反应,运用制得的多克隆抗体定位了基质蛋白在感染狂犬病病毒的BHK-21细胞中的位置。结果表明成功制得了抗狂犬病病毒M蛋白的多克隆抗体,为研究狂犬病病毒M蛋白功能奠定了基础。 相似文献
100.
不同养殖模式翘嘴鲌肌肉营养品质比较 总被引:1,自引:0,他引:1
为评价池塘与大湖不同养殖模式翘嘴鲌(Culter alburnus)肌肉营养品质差异,试验分析了商品翘嘴鲌肌肉常规营养成分、氨基酸、脂肪酸、矿物元素含量等营养指标。结果表明:大湖翘嘴鲌肌肉水分含量显著低于池塘翘嘴鲌(P<0.05),粗蛋白质含量高于池塘翘嘴鲌,差异不显著(P>0.05)。池塘与大湖翘嘴鲌肌肉,除了赖氨酸和组氨酸以外(P<0.05),绝大部分氨基酸含量均无显著性差异(P>0.05)。大湖翘嘴鲌肌肉的总氨基酸、必需氨基酸和鲜味氨基酸含量分别较池塘翘嘴鲌高出2.72%、2.87%和2.50%。根据氨基酸评分(AAS)和化学评分(CS)结果,池塘与大湖翘嘴鲌肌肉中第一限制性氨基酸均为蛋氨酸+胱氨酸,赖氨酸相对含量最高,必需氨基酸指数(EAAI)分别为68.81和69.62。池塘翘嘴鲌的棕榈油酸(C16:1)含量显著高于大湖翘嘴鲌(P<0.05),而大湖翘嘴鲌肌肉的单不饱和脂肪酸(MUFAs)、高不饱和脂肪酸(HUFAs)、必需脂肪酸(EFA)、EPA+DHA含量则高于池塘翘嘴鲌(P>0.05)。试验检测了池塘与大湖翘嘴鲌肌肉11种矿物元素,其中镁有显著差异(P<0.05),重金属元素(铬、镉、铅)含量均在限量范围以内。综上所述,大湖养殖翘嘴鲌营养品质优于池塘养殖。 相似文献