Effect of Nutrient Restriction and Compensation on Weight,Serum Indexes and Gene Expression of Chest Fat Adipokines in Mongolian Lamb

To study the effect of nutrient restriction and compensation on weight,serum indexes and gene expression of chest fat adipokine in Mongolian lamb,thirty male lambs were randomly divided into control group (20.26 kg± 3.63 kg) and feed restricted group (21.29 kg±3.00 kg).The experiment lasted for 120 days,including 60 days for feed restriction and 60 days for compensatory feed.At the end of each stage,five lambs from each group were slaughtered and chest fat was collected.Serum concentration of triglycerides,non-esterified fatty acids (NEFA),total cholesterol were measured.Quantitative Real-time PCR were used to determine Adiponectin,Visfatin,PPAR-γ and ACC genes expression.The results showed that:①The lamb body weight of restricted group kept maintain level and that of control group showed a increase tendency.During the compensatory period,the average daily gain (ADG) of restricted group was significantly higher than control group (P< 0.05).②During the restriction period,serum triglycerides concentration of lambs in restricted group was significantly decreased at day 30 and 60 (P< 0.05),and NEFA concentration was significantly increased at day 30 (P< 0.05).After 60 days of nutritional compensation,all serum parameters we tested were not significantly different between restrict group and control group (P >0.05).③During the restriction period,PPAR-γ and ACC gene expression in restricted group were significantly lower than that of control group (P< 0.05),while no significant differences were found during the compensation period (P>0.05).Adiponectin and Visfatin genes expression in chest fat was not significantly changed throughout the experiment (P >0.05).We could know that nutritional restriction reduced fatty acid synthesis and adipocyte differentiation ability,adipose tissue was mobilized energy metabolism,and total cholesterol was recoveried growth on the compensation.However,the ACC and PPAR-γ genes in restricted group were significantly decreased with the body weight increased rapidly during the compensatory stage.Adiponectin and Visfatin were not significantly different between restricted and compensatory stages.     

牛胚胎移植的实践操作

主要介绍受体母牛的选择标准、营养和管理、疾病控制、同期发情处理及胚胎移植的具体操作方法,最后介绍了通过添加激素促进胚胎移植后母牛的妊娠。     

UPLC-MS/MS法检测动物性食品中19种β-受体激动剂残留

建立了前处理过程较为简便、能同时检测猪、牛和羊的肌肉、肝脏、肾脏和鸡蛋中特布他林、齐帕特罗、沙丁胺醇、西马特罗、西布特罗、克仑塞罗、羟甲基克伦特罗、克仑丙罗、氯丙那林、莱克多巴胺、克仑特罗、妥布特罗、溴布特罗、克仑潘特、班布特罗、马布特罗、马喷特罗、苯乙醇胺A和喷布特罗19种β-受体激动剂的UPLC-MS/MS方法。样品经乙腈-异丙醇混合溶液(4∶1,V/V)提取后,用β-葡萄糖醛苷酶/芳基硫酸酯酶酶解,混合型阳离子交换固相萃取柱净化,然后用UPLC BEH C18色谱柱分离,以0.1%甲酸乙腈溶液和0.1%甲酸水溶液为流动相进行梯度洗脱,基质匹配溶液内标法或外标法定量。结果表明:19种β-受体激动剂在1~50 ng/m L基质匹配标准溶液浓度范围内呈现良好线性关系,相关系数R2均大于0.990;在猪、牛和羊的肌肉、肝脏、肾脏和鸡蛋中的检测限均为0.1 ng/kg,定量限均为0.5 ng/kg。从0.5、1、2和5 ng/kg四个添加浓度检测结果可以看出,19种药物的回收率范围为60%~120%,批内、批间相对标准偏差均小于20%。该方法具有简便快捷、灵敏度高、定性准确等特点。     

微小隐孢子虫微线蛋白GP900与MDBK细胞互作蛋白的筛选

通过筛选与微小隐孢子虫微线蛋白GP900相互作用的MDBK细胞蛋白,为进一步揭示微小隐孢子虫入侵宿主细胞的分子机制提供依据。首先构建重组原核表达质粒pGEX-4T-GP900,表达并纯化重组GP900蛋白;然后将重组GP900蛋白与MDBK细胞裂解液孵育,免疫共沉淀获得结合蛋白,质谱法分析与GP900互作的蛋白;最后用酵母双杂交进行验证。结果表明,成功构建pGEX-4T-GP900表达质粒,并纯化获得大小为43 kDa的重组GP900蛋白;免疫沉淀-质谱法筛选到2种与GP900相互作用的MDBK细胞蛋白,分别为膜联蛋白A2和热休克蛋白5;酵母双杂交技术验证了GP900与以上2种蛋白均有相互作用。为进一步阐明微小隐孢子虫入侵宿主细胞的分子机制奠定了基础。     

酿酒酵母细胞壁可通过TLR2受体调控绵羊瘤胃上皮细胞表达SBD-1

旨在研究酿酒酵母细胞壁对体外培养绵羊瘤胃上皮细胞β-防御素-1(sheep beta-defensin-1,SBD-1)表达的影响及其调控途径,为揭示酿酒酵母细胞壁对机体免疫的调控机制提供理论依据。本研究将不同质量浓度的酿酒酵母细胞壁提取物(0,25,50,100,200,400mg/L)作用于绵羊瘤胃上皮细胞不同时间(0,2,4,8,12,24h)后,检测上皮细胞SBD-1和Toll样受体-2(TLR2)mRNA表达水平,并进一步通过TLR2阻断试验来证实TLR2是否介导酵母细胞壁促进SBD-1表达。结果表明,不同浓度的酵母细胞壁刺激瘤胃上皮细胞时,随着细胞壁浓度的增加SBD-1mRNA表达量呈先升高后降低的趋势,且酿酒酵母细胞壁质量浓度为200mg/L刺激12h时,SBD-1 mRNA表达量达到峰值,与对照组和其他时间组相比差异显著(P0.05);用质量浓度为200mg/L的酿酒酵母细胞壁刺激绵羊瘤胃上皮细胞不同时间,同样在12h时,TLR2的mRNA表达量达到最大;阻断试验表明TLR2可介导SBD-1的表达。本研究结果表明酿酒酵母细胞壁可促进绵羊瘤胃上皮细胞SBD-1的表达,且质量浓度200mg/L时,刺激瘤胃上皮细胞12h时SBD-1的表达量达到最高,而TLR2参与该调控过程。     

应用电子鼻分析60Co-γ辐照对干辣椒整体气味的影响

为了探索~(60)Co-γ辐照剂量对干辣椒整体气味的影响,利用电子鼻检测不同辐照剂量(0 kGy、1 kGy、2 kGy、3 kGy、5 kGy、10 kGy、15 kGy)处理中的挥发性风味物质,并对挥发性风味物质的主要类别进行分析。结果表明:辣椒辐照处理后,电子鼻部分传感器的响应值与对照产生显著差异,并且辐照前后主要挥发性风味物质的类别都是无机硫化物类、有机硫化物类、甲基类、氮氧化合物类及醇醛酮类;主成分分析累计方差贡献率达99.513%,但是各样品判别指数在0.049～0.797之间,线性判别分析的累积贡献率仅为72.450%,均不能区分干辣椒样品,说明辐照处理(1～15 kGy)对干辣椒整体风味影响较小。     

猪FcγRⅢ和γ链共转染Marc-145细胞系的建立

为了建立稳定表达猪FcγRⅢ (Porcine Fc gamma receptor Ⅲ,poFcγRⅢ )的Marc-145细胞系,从PAM细胞中提取总RNA,应用RT-PCR技术获得猪FcγRⅢ和γ链的cDNA,并构建PIREShyg3-γ和pcDNA3.1- FcγRⅢ真核表达质粒;用脂质体共转染Marc-145细...     

搜索微量血迹气味训练可行性探讨

重特大杀人疑难案件发生时,犯罪嫌疑人为了转移侦查视线,时常在室内杀人碎尸,室外抛尸。在第一现场时常为了掩盖犯罪物证,对犯罪现场伪装处理,进行冲洗,粉刷掩盖痕迹物证逃避打击,给刑侦技术人员认     

不同牛品种胚胎移植效果对比试验

奶牛品种质量差已成为制约我国奶牛业发展的主要因素,采用常规人工授精技术进行改良,所耗时间长,而胚胎移植技术是实现低产牛改良和优良个体迅速扩大的有效措施。在养牛业发达的国家,胚胎移植技术在20世纪80年代末开始应用于生产实践。我国20世纪70年代开展了胚胎移植技术的研究工作,并取得成功,试验性小规模的在部分省(区)进行应用,没有大规模应用在生产中而取得效益。     

警犬气味鉴别技术在交通肇事案件中的应用

十年来，唐山市公安局将警犬气味鉴别技术成功应用于交通肇事案件侦破和处理的准确率达到了l00％，实现了当事人、保险公司、交通事故处理部门和人民法院“四满意”，上访率为零，为国家挽回经济损失200余万元。更重要的是，使长期以来警犬鉴别法律地位尚未明确的现象被打破，警犬鉴别作为诉讼证据被法庭采用，为警犬鉴别工作闯出了一片新天地。