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101.
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The peroxisome proliferator-activated receptors (PPARs) are the members of superfamily of nuclear hormone receptors. A great number of studies in rodent and human have shown that PPARs were involved in the lipids metabolism. The goal of the current study was to investigate the expression pattern of PPAR genes in various tissues of chicken. The tissue samples (heart, liver, spleen, lung, kidney, stomach, intestine, brain, breast muscle and adipose) were collected from six Arber Acres broilers (8 weeks old, male and female birds are half and half). Semi-quantitative RT-PCR and Northern blot were used to characterize the expression of PPAR-alpha and PPAR-gamma genes in the above tissues. By semi-quantitative RT-PCR, the results showed the expression level of PPAR-alpha gene was higher in brain, lung, kidney, heart and intestine, medium in stomach, liver and adipose than in spleen, and it did not express in breast muscle. The expression level of PPAR-gamma gene was higher in adipose, medium in brain and kidney than in spleen, heart, lung, stomach and intestine, but it did not express in liver and breast muscle. Northern blot results showed that PPAR-alpha gene expressed in heart, liver, kidney and stomach, and the intensity of hybridization signal was the stronger in liver and kidney than in other tissues, however, PPAR-gamma gene only expressed in adipose and kidney tissues. The results of this study showed the profile of PPAR gene expression in the chicken was similar to that in rodent, human and pig. However the expression profile of chicken also have its own specific trait, i.e. compared with mammals, PPAR-alpha gene can not be detected in skeletal muscle and PPAR-gamma gene can be stronger expressed in kidney tissues. This work will provide some basic data for the PPAR genes expression and lipids metabolism of birds. 相似文献
103.
全混合日粮(TMR)是现代奶牛场普遍采用的饲喂技术。本文就目前我国奶牛养殖场(户)使用TMR日粮应具备的条件及使用方法进行介绍。 相似文献
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Partitioning the respiratory components of soil surface CO2 efflux is important in understanding carbon turnover and in identifying the soil carbon sink/source function in response to land-use change. The sensitivities of soil respiration components on changing climate patterns are currently not fully understood. We used trench and isotopic methods to separate total soil respiration into autotrophic (R A ) and heterotrophic components (R H ). This study was undertaken on a Robinia pseudoacacia L. plantation in the southern Taihang Mountains, China. The fractionation of soil 13CO2 was analyzed by comparing the δ13C of soil CO2 extracted from buried steel tubes with results from Gas Vapor Probe Kits at a depth of 50 cm at the preliminary test (2.03‰). The results showed that the contribution of autotrophic respiration (fR A ) increased with increasing soil depth. The contribution of heterotrophic respiration (fR H ) declined with increasing soil depth. The contribution of autotrophic respiration was similar whether estimated by the trench method (fR A , 23.50%) or by the isotopic method in which a difference in value of 13C between soil and plant prevailed in the natural state (RC, 21.03%). The experimental error produced by the trench method was insignificant as compared with that produced by the isotopic method, providing a technical basis for further investigations. 相似文献
106.
2021年,沂南县推进动物疫病强制免疫“先打后补”工作,依托“鲁牧云”信息平台,通过强化组织领导,加强政策宣贯,强化人员培训,放开强免疫苗经营渠道,提供抗体检测无偿服务等措施,提升了养殖场户“先打后补”的积极性、自主性、灵活性,强化了养殖场户动物防疫主体责任,满足了养殖场户疫苗多样化需求。但由于 “先打后补”补助金额少、社会化服务不规范、基层动物防疫体系弱化、缺少配套工作经费等原因,部分养殖场户实施“先打后补”的积极性不高。建议通过规范社会化服务组织,强化培训水平,提高补助标准,强化三级(县乡村)基础设施建设,升级“鲁牧云”等措施,确保“先打后补”政策惠及更多养殖场户。 相似文献
107.
内蒙古寒冷干旱地区苜蓿栽培技术模式 总被引:2,自引:0,他引:2
苜蓿是内蒙古寒冷干旱地区重要的牧草之一,在近几年的农业结构调整和生态治理中,得到了快速发展,但缺乏规范的苜蓿种植管理技术。本文阐述的苜蓿栽培技术模式,是在林西县多年苜蓿生产实践基础上产生的,而后又在生产实践中不断改进完善后形成的。该技术模式着重介绍了在内蒙古寒冷干旱地区建植苜蓿人工草地时需着重考虑的四个方面,即苜蓿品种的选择原则、播种要点、田间管理及收获技术。 相似文献
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试验选择6头500—800kg屡配不孕的荷斯坦母牛采用“诱乳素”进行诱导泌乳处理。结果表明,“诱乳素”在春季对母牛处理后开始出现泌乳的时间有差异,但到23天后,其产奶量可逐渐达到20kg。对体重大的母牛,虽然诱导泌乳处理时加大了药物的剂量,处理的时间延长,但开始出现泌乳的时间却推迟到8~9天,达到产奶高峰的时间也较晚。采用“诱乳素”处理除了对空怀母牛有明显的诱导泌乳作用外,对母牛的诱导发情亦有明显的作用。采用“诱乳素”处理空怀母牛,不仅可以在短期内达到诱导泌乳的效果,而且可以改善母牛的生殖功能,使不发情的母牛发情趋于正常,提高了其繁殖率。 相似文献