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1.
Mark D. Rawling Nicola Pontefract Ana Rodiles Ilektra Anagnostara Eric Leclercq Marion Schiavone Mathieu Castex Daniel L. Merrifield 《Journal of the World Aquaculture Society》2019,50(6):1108-1122
Fish were fed a single‐strain yeast fraction (SsYF; 2 g/kg) or a multistrain yeast fraction (MsYF; 0.8 g/kg) for 10 weeks. The results demonstrated significant (p ≤ 0.03) elevations in weight gain, specific growth rate, protein efficiency ratio, and feed conversion ratio in fish fed the yeast fraction‐supplemented diets. In the distal intestine, a significant elevation in microvilli density was observed after 5 and 10 weeks of dietary supplementation with MsYF and SsYF, respectively, compared to control fed fish (p < 0.001). A significant elevation (p = 0.02) in the perimeter ratio was observed in fish fed diets supplemented with the yeast fractions. After 10 weeks of feeding on the experimental diets, Rt‐qPCR demonstrated a significant downregulation (p < 0.05) in the stress response genes, heat‐shock protein 70 (hsp70) and proliferating cell nuclear antigen (pcna), in fish fed diets supplemented with the yeast fractions. Significant (p < 0.05) elevations in interleukin 1‐beta (il1β) and interleukin‐10 (il10) gene expression were observed in fish fed diets supplemented with the MsYF compared to the other dietary groups. These findings suggest that feeding an MsYF specifically at a lower incorporation rate < 1 g/kg, compared to a commercial SsYF at 2 g/kg, is effective in improving the intestinal health status and growth performance of European seabass. 相似文献
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Gustavo Pereira Valani Aline Fachin Martíni Laura Fernanda Simes da Silva Renata Cristina Bovi Miguel Cooper 《Soil Use and Management》2021,37(1):22-36
Integrated crop–livestock–forest is a promising strategy to improve soil quality. It comprises four different integrated farming systems: crop–livestock, crop–forest, forest–livestock and crop–livestock–forest. This work systematically reviewed studies about integrated crop–livestock–forest systems and soil quality. A total of 92 papers were retrieved from the Web of Science—Clarivate Analytics platform, and the following information was analysed: publication year, institution, region of the studied site, type of integrated system, soil type, tillage system, maximum soil depth and the soil quality indicators assessed. Most studies were published in the second half of the 2010s. Brazil is a prominent focus of research about soil quality and integrated crop–livestock–forest systems, with significant contribution from its central and southern regions. The Embrapa was the main publishing institution, present in over one‐third of the studies. Crop–livestock was the most common integrated system, Ferralsols was the most common soil group, and most of the studied soils were clayey. No tillage was the main tillage system. Most studies focused on the topsoil, assessing physical and/or chemical soil quality indicators. More emphasis on biological indicators of soil quality is required, as well as assessments integrating biological, physical and chemical indicators of soil quality. Future works should compare different integrated systems, including assessments deeper in the soil profile, especially in systems with the forest component, and also in sandy and silty soils. Soil quality indicators that have been rarely used should be further tested. Novel indicators should be added to better understand the promotion of soil quality by integrated crop–livestock–forest systems. 相似文献
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旨在评估宁夏地区荷斯坦牛乳房性状的遗传水平。本研究使用DMU(v6.0)软件的AI-REML模块结合EM算法并配合多性状动物模型对宁夏地区12 415头荷斯坦牛,包括111 735个观察值的9个乳房性状进行遗传参数估计,运用主成分分析法(PCA)探讨构象性状之间的关系。结果表明,宁夏地区荷斯坦牛乳房性状遗传力处于中等偏低水平,乳房深度遗传力值为0.242,乳房质地为0.080,悬韧带为0.183,前乳房附着为0.230,前乳头位置为0.231,前乳头长度为0.173,后乳房高为0.272,后乳房宽为0.378,后乳头位置为0.169。各性状遗传相关范围为-0.277~0.706,表型相关范围为-0.084~0.316。研究共筛选出特征值≥1的4个主成分,占总方差的64.19%,且9个乳房性状在前3个主成分中已全部体现,荷载系数均在0.4以上。本研究通过对宁夏地区奶牛DHI数据的深入挖掘和遗传参数估计,准确地把握了宁夏奶牛群体的结构特征,对于奶牛的选种选配和育种规划具有重要意义。 相似文献
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为掌握典型药物在农作物中的污染特征及健康风险,保障农产品质量安全,利用超声萃取-固相萃取-高效液相色谱/串联质谱(LC-MS/MS)技术,对围场县全县马铃薯中5大类(磺胺类、四环素类、氟喹诺酮类、大环内酯类及其他类)25种药物污染水平及富集效果进行了调查,并对健康风险进行了评价。结果表明,有20种目标物被检出,不同目标物检出率差异显著,检出含量范围为0.13~3.67μg·kg-1,单种污染物最高检出含量为17.0μg·kg-1。马铃薯对目标污染物的富集系数范围在0.01~39.6之间,最大富集系数为61.8。畜禽粪便是马铃薯中药物残留的主要来源,尽管整体检出水平和健康风险相对较低,但长期摄入与协同作用引发的潜在健康风险不容忽视。因此,仍需严控污染源头,推进畜禽粪便安全资源化利用,确保农田环境质量及农产品安全品质。 相似文献
6.
lcylp@sohu.com 《勤云标准版测试》2006,(3)
采用生态系统健康的理论和评价方法分析评价农田生态环境问题具有重要的理论和现实意义,应用生态健康指数定量评价农田健康水平是生态系统管理的重要内容。以武川县农田为研究对象,选择水分、生物量、幅宽等代表性指标,分析了不同作物覆盖下农田生态健康指数。结果表明:不同种植模式间农田健康指数差别明显。播种期较早的小麦田最为健康,没有采用地膜覆盖的马铃薯田健康指数最低,而采用地膜覆盖的马铃薯田健康指数比较高。推广小麦栽培和覆膜栽培是北方农牧交错带农田很好的经营管理模式,具有推广价值,是缓解该地区环境的有效手段之一。 相似文献
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Ross Gordon COOPER Jaroslaw Olav HORBANCZUK Noboru FUJIHARA 《Animal Science Journal》2004,75(2):89-95
The ostrich is an important animal in many livestock industries. A significant threat to this industry is losses from diseases. Newcastle disease is a notifiable, highly contagious viral infection of ostriches. Avian influenza may be transmitted from waterfowl, shorebirds and gulls to ostriches. Borna disease virus is a viral neurotropic infection spread mainly by rodents and felines. Crimean‐Congo hemorrhagic fever is a viral disease transmitted by Hyalomma ticks to humans. Avipoxvirus afflicts ostrich chicks and is transmitted by mosquitoes or by direct contact with a pox lesion. Maintenance of a healthy and profitable enterprise requires the implementation, with assistance from the local veterinary authority, of comprehensive, practical and effective methods of health management and preventative medicine. 相似文献
9.
随机抽取荷斯坦奶牛 472头 (1~ 11胎 )进行奶牛隐性乳房炎的检测 ,乳用特征性状 (楞角性、尻宽、尻角度、后肢侧视、蹄角度 )的线性评定 ,以及隐性乳房炎与乳用特征的相关性分析。结果表明 :奶牛隐性乳房炎的乳区阳性率与楞角性、尻宽、尻角度、后肢侧视、蹄角度的相关系数分别为 0 1171、0 10 3 0、0 0 681、0 0 180、-0 12 65 ,其中与楞角性、尻宽分别达到显著水平 (P <0 0 5 )的正相关 ,与蹄角度达极显著 (P <0 0 1)的负相关。奶牛阳性率与楞角性、尻宽、尻角度、后肢侧视、蹄角度的相关系数分别为 0 0 967、0 0 5 61、0 0 2 82、0 0 12 7和 -0 0 670 ,其中除与楞角性为显著水平 (P <0 0 5 )的正相关 (0 0 967)外 ,其余均不显著 (P >0 0 5 )。 相似文献
10.