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81.
文章旨在研究不同脂肪水平日粮添加不同粒度吡啶甲酸铬对育肥猪生长性感、胴体特性及胰岛素敏感性的影响。试验选择平均体重为(51.8±3.45)kg的三元猪768头,试验采用2×4多因素方差设计,共2个脂肪水平(低脂和高脂),4个不同粒度吡啶甲酸铬水平(0 mg/kg,400 mg/kg粒度为320μm,15μm和50 nm的吡啶甲酸铬),其中每组4个重复,每个重复24头猪。试验共开展42 d。日粮添加吡啶甲酸铬较对照组显著提高了试验21 d肥猪的日增重(P<0.05);高脂日粮较低脂日粮显著提高了该阶段日增重(P<0.05)。日粮添加不同粒径吡啶甲酸铬显著提高了肥猪的屠宰率(P<0.05),吡啶甲酸铬组较对照组显著降低了背膘厚度(P<0.05);不同粒径吡啶甲酸铬显著提高了腰肌深度(P<0.05),吡啶甲酸铬和脂肪水平对腰肌深度的影响具有显著交互作用(P<0.05),其中添加吡啶甲酸铬的高脂日粮较其他组显著提高了腰肌深度(P<0.05)。日粮添加吡啶甲酸铬和脂肪水平对腰肌深度的影响具有显著交互作用(P<0.05),其中添加吡啶甲酸铬的高脂日粮较其他组显著提高了腰肌深度(P<0.05)。日粮添加吡啶甲酸铬显著降低了稳态模型(P<0.05),而高脂日粮显著提高了定量胰岛素敏感性检测指标(P<0.05)。综上所述:日粮添加吡啶甲酸铬可以提高育肥猪生长性能及胰岛素敏感性,其中微米和纳米级吡啶甲酸铬可以改善育肥猪胴体特性。 相似文献
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The impact of the chromium supplementation on insulin signalling pathway in different tissues and milk yield in dairy cows 下载免费PDF全文
M. Pantelić L. J. Jovanović R. Prodanović I. Vujanac M. Đurić T. Ćulafić S. Vranješ‐Đurić G. Korićanac D. Kirovski 《Journal of animal physiology and animal nutrition》2018,102(1):41-55
Thirty days before expected time of parturition, 20 Holstein cows were divided into ?Cr and +Cr groups. From day 25 before parturition (BP ) up to day 30 after parturition (AP ), +Cr cows received 10 mg of Cr (chromium‐enriched yeast) daily. Muscle and adipose tissue samples were taken at days ?30, ?10, +7 and +10 related to parturition, when body condition score (BCS ) was also determined. Hepatic tissue samples were taken at days ?10 and +7. Tissue samples were used for determination of the insulin signalling pathway protein expressions. Intravenous glucose tolerance test (IVGTT ) was performed at days ?28, ?7, +10 and +30. Milk yield was recorded during first 14 weeks AP . Milk composition was obtained at days 7 and 28 AP . At day 10 BP , protein content of β ‐subunit of insulin receptor (IR β ) was significantly higher (p ? 0.05) in muscle, and phosphorylation of insulin receptor substrate 1 at serine 307 (pIRS ‐1 Ser307) was significantly lower (p ? 0.05) in hepatic tissue of +Cr group. After parturition, pIRS ‐1 Ser307 was significantly lower in muscle tissue at days 7 and 28 (p ? 0.05 and p ? 0.001, respectively), while phosphorylation of Akt at serine 473 (pA kt Ser473) was significantly higher (p ? 0.01) in hepatic tissue at day 7 AP in +Cr group. Chromium had opposite effect on insulin kinetics during IVGTT s obtained BP and AP . Insulin secretion was significantly reduced at day 7 BP and significantly enhanced at day 10 AP , when NEFA concentration was also significantly increased. Milk yield and ECM value were depressed in +Cr group. DMI and BCS were significantly enhanced in +Cr group at day 7 BP . In conclusion, chromium modulates insulin signalling pathway in dairy cows, but targeted signalling molecules are different in antepartal then post‐partal period, probably due to duration of exposure to chromium and different energy status between those periods. 相似文献
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《The Journal of Applied Poultry Research》2008,17(4):476-481
Chromium has been considered by many nutritionists as an essential nutrient for animals and humans. Research on the use of Cr from organic sources in poultry is limited. Two experiments were conducted to determine the effects of dietary addition of 0, 200, 400, or 800 ppb Cr as chromium propionate on growth performance and carcass traits in 0- to 42- or 0- to 49-d-old broilers. The results of these experiments indicate that Cr as chromium propionate improved feed efficiency in the later phases of growth and decreased mortality in one experiment but not another. Also, chromium propionate supplementation had no effect on carcass traits. 相似文献
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针对六价铬分析实验中显色剂保存较易变色和操作不够简便的问题,提出了在显色剂配制时,用95%乙醇作为溶剂加入少量酸配制二苯碳酰二肼溶液。实验过程加酸的步骤中,使用(1+1)硫酸和(1+1)磷酸等体积混合酸。通过实验对比发现:改进的方法能延长的显色剂的保存时间,简化实验操作步骤,并且保证了实验分析的精密度和准确度。 相似文献
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通过营养液沙培盆栽试验,研究了水稻幼苗的根长、株高和鲜重对高氯酸盐(ClO4^-)、六价铬(Cr^6+)及其复合污染(ClO4^-+Cr^6+)胁迫的响应。结果表明,随着污染物处理浓度的提高,ClO4^-、Cr^6+和ClO4^-+Cr^6+对水稻幼苗主要生长指标根长、株高和鲜重的抑制作用越明显,呈现出明显的浓度-效应关系;在同一浓度下,ClO4^-、Cr^6+和ClO4^-+Cr^6+对水稻幼苗根长、株高和鲜重的抑制率呈明显的时间-效应关系,处理时间越长,抑制率越高;复合污染对水稻生长的抑制效应大于其中任一污染物在同浓度条件下的单一污染的影响,且随着浓度和时间的增加,抑制作用也越明显;复合污染对水稻幼苗生长的交互作用类型因处理时间和浓度组合的不同而更趋复杂。 相似文献