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81.
S. Delin 《Soil Use and Management》2011,27(4):415-426
The nitrogen (N) fertilizer effect of layer hen and broiler manure applied at different times on spring barley yield was studied in seven Swedish field experiments during 2005–2008. Two experiments had parallel field incubations to study N release after fertilizer application. The effect of total N in manure on N offtake was 30–40% that of mineral N, except in a dry year, when the effect was very low. Although the relative proportions of ammonium N, uric acid N and other N differed between the hen and broiler manure, the effect of total N was similar for both. In field incubations, mineral N decreased from 75 to 60% of total N applied in hen manure, whereas it increased from 20 to 50% in broiler manure, because of net immobilization and release, respectively. The limited fertilizer nitrogen replacement value, corresponding to only 30–40% of total N, could be as a result of ammonia volatilization after rather shallow incorporation with harrow. Net N release from broiler manure lasted for 6–8 weeks after application, after which it generally ceased. In some cases, manure application in early spring gave better yield effects than application at sowing, probably because of better synchronization of the N release with crop N requirements. The residual N effect on the N offtake in crop in the year after manure application was on average 3% of the total N applied, equivalent to a fertilizer replacement value of about 6%. 相似文献
83.
松针粉富含多种营养成分,并且具有一定的药用价值。文章对我国松针的资源概况、松针粉的营养价值、药效及在生产上的应用情况进行概述,并对松针粉未来的研究方向进行展望。 相似文献
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Yuval Ramot Michal Steiner Netanel Amouyal Yossi Lavie Guy Klaiman Abraham J. Domb Abraham Nyska Tal Hagigit 《Journal of toxicologic pathology》2021,34(1):11
Fracture-related infections remain a leading cause of morbidity and mortality. We aimed to establish a simple contaminated radial osteotomy model to assess the efficacy of a biodegradable polymer poly(sebacic-co-ricinoleic acid) [p(SA-RA)] containing 20% w/w gentamicin. A unilateral transverse osteotomy was induced in Sprague-Dawley (SD) rats, followed by application of Staphylococcus aureus suspension over the fracture. After successfully establishing the contaminated open fracture model, we treated the rats either systemically (intraperitoneal cefuroxime), locally with p(SA-RA) containing gentamicin, or both. Control groups included non-contaminated group and contaminated groups that were either untreated or treated with the polymer alone. After 4 weeks, the bones were subjected to micro-CT scanning and microbiological and histopathology evaluations. Micro-CT analysis revealed similar changes in the group subjected to both local and systemic treatment as in the non-contaminated control group. Lack of detectable bacterial growth was noted in most animals of the group subjected to both local and systemic treatment, and all samples were negative for S. aureus. Histopathological evaluation revealed that all treatment modalities containing antibiotics were highly effective in reducing infection and promoting callus repair, resulting in early bone healing. While p(SA-RA) containing gentamicin treatment showed better results than cefuroxime, the combination of local and systemic treatment displayed the highest therapeutic potential in this model. 相似文献
87.
Kasumi Sudo Mariko Ochiai Naoyuki Aihara Noriyuki Horiuchi Atsushi Yamamoto Sachiko Matsumoto Koji Oishi 《Journal of toxicologic pathology》2021,34(2):137
Batch safety tests (BSTs) of veterinary vaccines are conducted using small laboratory animals to assure the safety of vaccines according to several criteria, including clinical signs and change in body weight. Although the latter is used as an evaluation index in BSTs, there have been no reports on the internal changes that affect body weight during the test period. Therefore, we analyzed BST via pathological examination of the tested animals. Here, BSTs were performed for 176 batches using mice and 126 batches using of guinea pigs. Most of the gross findings could be classified into four lesion types (nodules, adhesions, ascites, no apparent signs), with only one vaccine inducing lesions that could not be classified into any of these four types. Histopathological examination revealed that the reactions caused by BST were pyogenic and/or granulomatous inflammation. Nodular or adhesive lesions comprised more severe pyogenic granulomatous inflammation than ascites or cases with no apparent gross lesions. These nodular or adhesive lesions were more frequently induced by vaccines that contained an adjuvant than by vaccines that did not contain an adjuvant. The cases with “exceptional” gross findings histologically presented severe necrosis of the hematopoietic system. Additional testing showed that these “exceptional” lesions were induced when a specific type of light liquid paraffin was injected along with other vaccine additives. Our results show that body weight loss and/or lesions during BST were induced by proinflammatory properties of the tested vaccines and that BST is a sensitive method for detecting unexpected effects of vaccine components. 相似文献
88.
试验以"LAMP+微流控"技术为基础,开发饲料动物源性成分检测芯片。针对牛、羊、猪、鸡的16srRNA靶序列,根据LAMP引物设计软件进行4种肉类LAMP引物设计。在LAMP优化试验、芯片优化测试、特异性验证试验和芯片应用测试中,进行最佳引物筛选测试和特异性测试。结果显示,筛选出的4种肉类最佳引物特异性强,最佳反应温度为65℃。芯片特异性验证试验的归一化荧光曲线显示,试验结果准确、特异性稳定。对饲料市场购买的16份样本中检测出的动物源性成分,采用中华人民共和国农业行业标准验证,符合率100%。微流控检测芯片的开发与应用为饲料中动物源性成分检测提供新方法,为饲料产品质量安全提供保障。 相似文献
89.
建立了超高效液相色谱-静电轨道阱质谱联用测定禽蛋中五氯苯酚残留量的分析方法。取均质后的禽蛋样品经乙腈溶液提取,加入无水硫酸镁和氯化钠进行脱水和盐析,高速离心分层后,取适量乙腈层溶液经0.1%(V∶V)甲酸稀释后,用酸性氧化铝粉末进行样品净化并以10000 r/min离心取上清液,过0.22μm滤膜后上机测定。使用反相色谱柱进行分离,流动相为乙腈:0.1%甲酸=75∶25,采用等度程序进行洗脱,静电轨道阱质谱进行定性定量分析。结果表明,五氯苯酚在0.5~100μg/kg范围内线性关系良好(r>0.995),方法的最低检出限为0.2μg/kg,最低定量限为0.5μg/kg,添加回收率在74.43%~96.85%之间,批内批间变异系数CV%<10%。该方法具有较好的准确度与精密度,适用于禽蛋中五氯苯酚残留量的测定。 相似文献
90.