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41.
Ramona Weishaar Robin Wellmann Amelia Camarinha-Silva Markus Rodehutscord Jörn Bennewitz 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2020,137(1):14-22
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
42.
LIU Ying-yu WANG Jin-quan WUMAIERJIANG Yahefu LIU Li-li LI Lin ZHANG Xiao-hong YAO Gang 《中国畜牧兽医》2016,43(4):985-990
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
43.
为研究饲料中添加不同水平的发酵豆渣对育肥猪生长性能、屠宰性能及经济效益指标的影响,采用单因素随机设计试验,选择体重相近的健康育肥猪80头随机分成4组,每组20个重复,每个重复1头,1组饲喂基础日粮为对照组,试验2、3、4组分别在基础日粮中添加5%、10%、15%发酵豆渣,预试验7 d,试验期56 d。结果表明:(1)试验3、4组的平均日增重较1组比分别提高15.5%、14.1%(P<0.05),料重比较1组比分别降低14.7%、11.9%(P<0.05),试验2、3、4组的平均采食量均高于1组(P>0.05);(2)试验2、3、4组的宰前活重、屠宰率高于1组(P>0.05),试验3、4组的瘦肉率、眼肌面积较1组比分别提高12.1%、8.9%、12.3%、8.2%(P<0.05),背膘厚较1组比分别降低8.5%、7.0%(P<0.05);(3)试验3、4组毛利润较1组比分别提高22.4%、18.0%。综上,添加10%发酵豆渣可以提高育肥猪的生长性能、屠宰性能及经济效益。 相似文献
44.
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
45.
S. L. Woods S. Sobolewska S. P. Rose I. M. Whiting A. Blanchard C. Ionescu 《British poultry science》2020,61(3):274-280
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
46.
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
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
47.
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
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50.
动物营养与饲料学实验教学改革与创新人才培养 总被引:1,自引:0,他引:1
根据动物营养与饲料学专业人才培养目标和《甘肃农业大学实践教学指导意见》的要求,通过从动物营养与饲料学实验教学大纲的修订,教学内容的编排,授课形式,授课时间和实验成绩考评等方面进行改革前后的比较与探讨,以期探索提高学生的动手操作能力,培养学生独立思考、发现问题、分析问题和解决问题能力的有效途径. 相似文献