怎样避免新购幼犬应激反应综合征

新购幼犬易主后,由于突然间的改变地点、饮食、环境等因素,一周内易发生以消化系统和呼吸系统为主要症状的疾病,我们称为应激反应综合征。轻者易引起幼犬的身体发育不良或者其他疾病的并发症,重者可以导致幼犬的死亡。如何避免这种疾病?笔者认为首先应做好养犬前的准备工作。准备好犬的居住场所、饲喂用具和常用药品等。在购买时,一定要细心观察,切勿操之过急。为防止购入病犬,应注意幼犬的双眼眼睑无分泌物,眼球清洁,双眼有神,无上下眼睑内翻外翻等;双耳耳阔耳道内干净,无异物、异味;鼻镜湿润、冰凉,不干燥、不发热,嗅、视、听觉良好;皮肤…     

HACCP在酸牛奶生产中的应用

本文主要探讨HACCP在酸奶生产中的应用，从质量卫生控制方面分析了生产过程中的危险因素，制定相应的控制方法和纠正措施，以取得高质量的酸牛奶。     

羊绒与羊毛的PCR-RFLP识别方法

羊绒价格昂贵,在销售中时常出现掺假现象,最常见的是用羊毛,因此精确识别羊绒和羊毛纤维的方法非常重要。本试验采用聚合酶链式反应-限制性片段长度多态（PCR-RFLP）的技术方法,利用提取的羊绒和羊毛线粒体基因组,根据细胞色素b（Cytochrome b）基因已知的DNA序列设计引物,通过内切酶SspⅠ进行酶切,得到不同的片段长度,根据酶切图谱鉴别羊绒和羊毛样品,用来进行羊绒掺假试验的定性检测。     

Comparative analysis of proteomic profiles between endometrial caruncular and intercaruncular areas in ewes during the peri-implantation period

The endometrium of sheep consists of plenty of raised intercaruncular areas （IC）. In order to better understand aglandular areas called caruncular （C）, and intensely glandular the endometrium involved mechanisms of implantation, we used LC-MS/MS technique to profile the proteome of ovine endometrial C areas and IC areas separately during the peri-implantation period, and then compared the proteomic profiles between these two areas. We successfully detected 1740 and 1813 proteins in C areas and IC areas respectively. By comparing the proteome of these two areas, we found 170 differentially expressed proteins （DEPs） （P 〈 0.05）, functional bioinformatics analysis showed these DEPs were mainly involved in growth and remodeling of endometrial tissue, cell adhesion and protein transport, and so on Our study, for the first time, provided a proteomic reference for elucidating the differences between C and IC areas, as an integrated function unit respectively, during the peri-implantation period. The results could help us to better understand the implantation in the ewes. In addition, we established a relatively detailed protein database of ovine endometrium, which provide a unique reference for further studies.     

用鳞片估计马来穿山甲个体数量

我国每年都能查扣到多起非法走私大量马来穿山甲鳞片进入境内的案件,由于不知如何根据鳞片来估计个体数量,而给森林公安机关立案、量刑与处罚带来极大不便。通过统计9头马来穿山甲鳞片的数目（Sm）、鲜重（Sfw）、干重（Sdw）,分别获得了以Sm、Sfw、Sdw为参数来估计马来穿山甲个体数量（N）的3个方程,它们是①Sm/929.8≤N≤Sm/681.8;②Sfw/835.4≤N≤Sfw/389.8;③Sdw/774.3≤N≤Sdw/367.9。执法部门在办理此类走私案件中能通过这些方程方便快捷地估算出走私物品的个体数量,能为同类案件的立案、量刑和处罚提供依据。     

High‐level exogenous trans10, cis12 conjugated linoleic acid plays an anti‐lipogenesis role in bovine mammary epithelial cells

Primary bovine mammary epithelial cells (BMECs) were treated by 0, 37.5, 75, 112.5, 150 μmol/L trans10, cis12 conjugated linoleic acid (CLA) to evaluate the effects of different level trans10, cis12 CLA on lipogenesis in BMEC. Addition of 75–150 μmol/L trans10, cis12 CLA reduced significantly the triacylglycerol (TAG) content (P < 0.05), but did not have inhibiting action on cell proliferation (P > 0.05). Treatment with 150 μmol/L trans10, cis12 CLA for 48 h resulted in a 17.1% reduction (P < 0.0001) of medium chain fatty acids (MCFA, C14 < C < C16), a 26.5% reduction (P < 0.0001) of unsaturated fatty acids (UFA) and a corresponding reduction of the mRNA abundance of acetyl coenzyme A (acetylCoA) carboxylase (ACC) (P = 0.046), fatty acid synthase (FAS) (P = 0.017) and stearoylCoA desaturase1 (SCD1) (P = 0.002). Another finding was that trans10, cis12 CLA elevated expression of diacylglycerol acyltransferase2 (DGAT2) (P = 0.020) and long chain acylCoA synthetases (ACSL) (P = 0.032). In conclusion, higher trans10, cis12 CLA, not low trans10, cis12 CLA, inhibited milk fat synthesis and changed fatty acid composition by regulating the expression of FAS, ACC, SCD1, DGAT2 and ACSL.     

生物技术在动物营养中的应用

生物技术的发展和应用已渗逢到生命科学的各个领域，生物技术应用于动物营养将极大促进动物营养学的发展。作者从基因工程、细胞工程、酶工程和微生物工程等4个方面来综述生物技术在动物营养中的应用现状。     

基因打靶备乳腺生物反应器研究进展

基因打靶技术是建立在胚胎干细胞和同源重组技术之上,可对基因组进行定点修饰的实验方法。用基因打靶技术制备乳腺生物反应器,克服了显微注射法的众多缺陷。本文简述了制备乳腺生物反应器过程中基因打靶的策略、靶细胞、打靶位点及国内外研究进展和展望等。     

浅谈猪瘟免疫失败的原因

猪瘟是由猪瘟病毒(HCV)引起的一种高度接触性传染病。猪瘟具有高度接触传染性,流行广泛,发病率、死亡率高,是危害我国养猪业最重要的传染病之一。我国自1954年成功研制出猪瘟兔化弱毒疫苗以来,有效地控制了猪瘟在我国的急性发生和大流行。但是,近些年来,转变为周期性、波浪式的     

H5N1亚型禽流感病毒NS1基因的原核表达及其ELISA检测方法的建立

采用RT-PCR技术扩增了禽流感病毒（AIV）A／Goose／HLJ／p46／2003（H5N1）的NSl基因，将其克隆于融合蛋白表达载体pMAL-c2X上，转化DH5α大肠埃希氏菌感受态细胞，经BamHⅠ和HindⅢ双酶切鉴定及序列分析，表明筛选到了重组质粒pc2X-NS1。SDS-PAGE电泳结果显示，重组质粒转化TB1大肠埃希氏菌后，经0．3mmol／L的IPTG诱导，融合蛋白MBP-NS1得到大量表达，融合蛋白以可溶形式存在，分子质量约为67ku。Western-blotting检测结果表明，融合蛋白MBP-NS1能够与H5N1亚型AIV活病毒感染康复鸭血清发生特异性反应，而不能够与H5N1亚型AIV灭活疫苗免疫鸭血清发生反应。试验初步建立了以纯化的融合蛋白MBP-NS1为包被抗原的间接ELISA检测方法，为AIV灭活疫苗免疫家禽与AIV感染家禽的鉴别诊断奠定了基础。