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氧气对低地鸡蛋胚胎死亡和孵化率的影响 总被引:4,自引:0,他引:4
通过模拟常压低氧和高海拔增氧孵化试验,研究了氧气浓度对低地良种鸡蛋胚胎死亡率和孵化率的影响。死亡胚胎的分布用2阶段增长模型分析。模拟2900m海拔常压低氧孵化增加了胚胎后期死亡率,使孵化率降低到接近2900m海拔实际孵化率水平;2900m海拔全期增氧孵化可以有效降低前期和后期胚胎死亡率,大大提高孵化率;阶段增氧孵化也能不同程度提高孵化率,改变胚胎死亡分布,其中效果最好的为前期增氧组。结果说明低氧是影响2900m海拔鸡蛋孵化的最主要因素。 相似文献
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灌注果寡糖对生长绵羊瘤胃发酵功能的影响 总被引:6,自引:0,他引:6
采用营养灌注技术研究了果寡糖对生长绵羊瘤胃发酵功能的影响。试验选取6只安装有永久性瘤胃瘘管的内蒙古半细毛羯羊,随机分为两组,试验组一灌注1.00%果寡糖,试验组二灌注2.00%果寡糖。结果表明:灌注果寡糖可以显著(P〈0.05)降低试羊的瘤胃液相pH和瘤胃内的NH3-N浓度,显著提高(P〈0.05)瘤胃内的VFA含量和MCP含量。两个灌注水平都可以提高生长绵羊的瘤胃发酵功能。但2.00%的灌注水平仅在瘤胃NH3-N浓度的降幅方面比1.00%的灌注水平显著增大(P〈0.05),在对瘤胃液相pH值、VFA含量和MCP含量的影响方面两个灌注水平没有显著差异(P〉0.05)。 相似文献
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Skeletal muscle is the most abundant tissue and the main component of muscle in animals.The process of skeletal muscle cell's proliferation and differentiation is the basis of muscle development and it's directly affects the meat production performance of domestic animals.It has been found that epigenetic modification plays an important role in regulating the proliferation and differentiation of skeletal muscle cells.In this study,the effects of epigenetics on skeletal muscle in terms of the effects of DNA methylation on the proliferation and differentiation of skeletal muscle cells,the selection and expression of factors regulated by histone acetylation,the regulation of non-coding RNA,and the effects of chromosome remodeling.Research progress in the process of muscle cell proliferation and differentiation,briefly describes the effects of different modification methods and factors on the two processes of skeletal muscle proliferation and differentiation.At the same time,the methods and means used by predecessor in the study of skeletal muscle proliferation and differentiation were reviewed,and then the role of apparent regulatory factors in skeletal muscle growth was analyzed.The purpose was to further explain the important role of epigenetic modification in the proliferation and differentiation of skeletal muscle,enhanced the understanding of the regulation of skeletal muscle proliferation and differentiation,provided a reference path for integration with animal production,and also provided skeletal muscle.Molecular regulation of such as growth and development provided more reference materials. 相似文献
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AIM:To investigate the effects of dietary fats and cholesterol on liver PPARα gene expression and body cholesterol (Chol) level in C57BL/6J mice. METHODS:The animals (n=75) were randomly divided into five groups and respectively received formula mash for 6 weeks. RESULTS:As compared to Chol diet, Chol+PUFA diet produced significantly higher liver cholesterol (P<0.01), serum total cholesterol (TC), focusing on HDL-C. While Chol+MUFA diet resulted in unchanged serum TC and lower liver cholesterol (P<0.01). Chol+SFA diet rsulted in higher liver cholesterol (P<0.01) and serum TC, focusing on LDL-C. Furthermore, Chol+PUFA diet increased the mRNA and protein content of PPARα (P<0.01) in liver, while Chol+MUFA and Chol+SFA diets decreased the mRNA content of PPARα significantly (P<0.01). CONCLUSIONS:These results indicated that addition of fats containing PUFA to diet high in cholesterol increased PPARα mRNA and protein expression, addition of fats containing MUFA or SFA to diet high in cholesterol decreased PPARα mRNA expression. The change of PPARα gene expression may further affect body cholesterol level. 相似文献