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71.
Most traits in animal breeding, including feed efficiency traits in pigs, are affected by many genes with small effect and have a moderately high heritability between 0.1 and 0.5, which enables efficient selection. Since the microbiota composition in the gastrointestinal tract is also partly heritable and was shown to have a substantial effect on feed efficiency, the host genes affect the phenotype not only directly by altering metabolic pathways, but also indirectly by changing the microbiota composition. The effect of the microbiota composition on the breeding value of an animal is the conditional expectation of its breeding value, given the vector with microbiota frequencies, that is The breeding value of an animal can therefore be decomposed into a heritable contribution that arises from an altered microbiota composition and a heritable contribution that arises from altered metabolic pathways within the animal, so Instead of selecting for breeding value , an index comprising the two components and with appropriate weights, that is , can be used. The present study shows how this breeding strategy can be applied in pig genomic selection breeding scheme for two feed efficiency traits and daily gain.  相似文献   
72.
新式墙面绿化在广州和深圳的应用研究   总被引:2,自引:0,他引:2  
新式墙面绿化对日益缩减的城市绿化环境至关重要,通过实地调查广州和深圳30个新式墙面绿化场所,分析其种植形式、植物种类、植物配置与景观效果,总结出深圳和广州新式墙面绿化的植物应用现状和景观效果,并讨论其发展前景。  相似文献   
73.
Modern cities use straightened and concrete watercourses with simple greening for riparian zones, which has been criticised for insensitivity to natural system integrity and cultural identity. This increases the challenge to urban ecologists, landscape designers and managers to conceive innovative and effective design solutions that do not jeopardise hydraulic efficiency yet are culturally acceptable to local communities. This paper introduces the field of local ecological knowledge (LEK) as rich sources of inspiration and design solutions to meet this challenge. LEK refers to knowledge and practices of various local cultures about the relationship of living beings (including humans) with their environments. Wepropose a pragmatic framework that integrates LEK with modern landscape design. It includes steps: (1) investigate existing practices, skills andmeasures relating to LEK; (2) explore how and whereLEKcan inspire or integrate withdesign. Here we propose three aspects for integration in accordance with the nature of landscaping process: overall structure, component and maintenance.(3)evaluate and test the integration in terms of its acceptability by local communities. Taking the riparian revegetation project of Hanfeng Lake Urban Wetland Park (Chongqing Municipality) as an example, we illustrate the utility of this framework. 11 local common practices relating to LEK were identified. According to thethree aspects for integration, alternative design solutions were offered. The survey showed that LEK based designwas more highly valued than other conventional ways in terms of useracceptance. We conclude that LEK provides actionable ecologically sound and culturally desirablesolutions for urbanlandscape. We also recognise that LEK evolveswith changing environments and new harmonious and dynamic human-nature relationships arecontinually re-forming. The process of acquisition and application of LEK could encourage multidisciplinary and synthetic approaches to urban ecosystems. Such adaptability and interdisciplinary engagementare crucial totoday’schanging and complexurban environments.  相似文献   
74.
相变材料能够储存或释放显热,在熔化或凝固过程中虽然温度不变但吸收的潜热却相当大。根据相变材料可以吸收环境热能并在需要时向环境发出热能的特征,研究相变材料在粮食仓储中的应用,减小外界环境对粮仓温度的影响,达到恒温绿色生态储粮的目的。  相似文献   
75.
In order to understand the situation of heavy metal residues of the beef industry chain in Yili area of Xinjiang.The heavy metals (Pb, As, Hg, Cr and Cd) in soil, feed and beef of the cattle farm were determined using the atomic absorption spectrometry.The results showed that the heavy metal (Pb, As, Hg, Cr and Cd)contents in soil samples were 0.03-0.20, 3.87-8.30, 0.15-0.23, 0.09-0.48 and 0.41-0.86 mg/kg, respectively.The heavy metal (Pb, As, Hg, Cr and Cd) contents in feed samples were 3.01-18.09, 75.35-94.27, 19.65-24.37, 0.06-1.04 and 1.81-8.46 μg/kg, respectively.The heavy metal (Pb, As, Hg, Cr and Cd) contents in beef samples were 0.23-0.54, 1.22-7.12, 0.28-0.53, 0.01-0.27 and 0.02-0.03 μg/kg, respectively.The correlation coefficient of the heavy metal element between soil and feed, feed and beef, soil and beef were 0.96, 0.99 and 0.98, respectively.It was concluded that the heavy metal (Pb, As, Hg, Cr and Cd) contents in soil, feed and beef of the cattle farms in Yili area did not exceed the standard and that in the soil, feed and beef had the high correlations.  相似文献   
76.
陈端海 《中国饲料》2021,1(8):85-88
中小型饲料企业是饲料产品经济发展中的重要组成部分,也是我国农牧行业经济发展的重要组成部分。随着计算机物联网技术的不断发展,当前线上销售模式应成为中小型饲料企业创新经济增长点的重点发展领域,而要想更好的发展线上运营模式必须考虑当前中小型饲料企业自身供应链管理物流配送的发展状况。本文研究分析当前中小型饲料企业供应链管理及物流配送的发展现状,通过对供应链管理的核心影响因素及中小型饲料企业所处内外部环境的深入研究,分析当前中小型饲料企业供应链管理发展问题背后的原因,并在此基础上提出针对中小型饲料企业供应链管理与物流配送的合理性建议与优化措施。 [关键词]中小型饲料企业|供应链管理|优化措施  相似文献   
77.
ABSTRACT

1. This study was conducted to determine the effect of different sources of selenium (Se) on breast and liver tissue deposition, apparent metabolisable energy (AME), growth performance and antioxidant status of broilers, measured as Se content in liver and breast tissues and glutathione peroxidase (GSH-Px) in blood, when used in 0–35 d broiler chicken diets.

2. A total of 200 male Ross 308 broilers were used in the feeding trial, which comprised two dietary phases, a starter from 0 to 21 d and finisher from 21 to 35 d of age. Four treatments with 10 replications each were used. A control diet (C) was formulated that was sufficient in protein and energy (230 and 215 g/kg of crude protein and 12.67 and 13.11 MJ/kg of metabolisable energy, respectively), for both phases, but contained background Se only from the feed ingredients. Diet 2 (IS) was supplemented with 10.35 g/t inorganic, elemental source of Se. Diet 3 (SY) was supplemented with 136.36 g/t selenised yeast, an organic source derived from Saccharomyces cerevisiae. Diet 4 (SS) was supplemented with 0.666 g/t sodium selenite, an inorganic source.

3. Birds fed the SY diet consumed less and weighed less than those fed IS or C (P < 0.05; 0–35 d of age), but there was no difference compared to birds fed SS diets. There were no differences in FCR or dietary AME between broilers fed different Se sources. All diets containing supplementary Se increased concentrations in the liver and breast muscle, and for GSH-Px levels in blood compared to birds fed the C diet (P < 0.001). Birds fed SY diets had greater Se levels in liver and breast tissues compared to birds fed any of the other diets (P < 0.001).

4. Diets supplemented with Se had variable effects on broiler growth performances and antioxidant status. Feeding Se from a yeast source has higher transfer into breast tissues. Feeding different sources and levels of Se to birds in a more challenging situation to induce oxidative stress may bring more conclusive results.  相似文献   
78.
香蕉副产物在家畜饲料方面的应用   总被引:1,自引:0,他引:1  
王春芳 《饲料研究》2020,43(3):144-146
香蕉皮和香蕉茎等香蕉副产物营养物质丰富,是可以饲料化的植物资源,可以作为饲料饲喂家畜,这样不仅减少了废弃香蕉副产物对环境的污染,重要的是资源得到充分利用。文章综述了香蕉副产物在饲料方面的国内外利用现状,期望为开发香蕉副产物的饲料化利用提供借鉴。  相似文献   
79.
翟玲 《中国饲料》2021,1(7):143-146
近些年来,饲料行业的发展处于上升趋势,其产量和销售额不断扩大,对企业的物流体系有了更高的要求。物流作为饲料企业运营的重要组成部分,影响着企业的效益和市场竞争力。区块链技术是信息发展的前沿技术,能够优化资源配置,提升饲料企业物流效率,从而增强核心竞争力。本文深入分析了目前我国饲料企业物流体系存在的一些问题,阐述了区块链技术在物流中的应用优势,提出了基于区块链技术的饲料企业物流体系的构建策略,为提升企业市场竞争力和实现长期稳步发展提供参考。 [关键词] 区块链技术| 饲料企业| 物流体系  相似文献   
80.
介绍了内蒙古畜牧业和草原生态现状,阐述了全区玉米秸秆生产量和饲料化利用情况,分析了玉米秸秆饲料进牧区的路径及其经济效益、生态效益、社会效益,以期为秸秆饲料进牧区提供理论依据。  相似文献   
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