高能日粮条件下半胱胺对大鼠抗氧化功能的影响

通过在正常日粮中添加高油脂来制备高能日粮,探讨高能日粮条件下,添加0、15、30、60mg/kg半胱胺(CS)对大鼠抗氧化功能的影响。试验结果表明:添加15、30mg/kg半胱胺均能显著提高大鼠抗氧化能力(P<0.05),30mg/kg半胱胺能使大鼠抗氧化能力恢复到接近正常日粮组水平,60mg/kg半胱胺对大鼠抗氧化能力的恢复无显著影响(P>0.05)。半胱胺添加的最适剂量为30mg/kg。     

半胱胺的生物学作用及应用

半胱胺具有多种生物学功能,如耗竭生长抑素,影响糖、蛋白质和脂肪的代谢,抗氧化和氧化作用,提高免疫功能。本文综述了半胱胺的生物学功能和应用情况。     

菜豆萎蔫病菌的血清检测鉴定技术研究

本研究对我国一类检疫性有害生物菜豆萎蔫病菌（Ｃｕｒｔｏｂａｃｔｅｒｉｕｍｆｌａｃｕｍｆａ－ｃｉｅｎｓｐｖ．ｆｌａｃｕｍｆａｃｉｅｎｓ，Ｃｆ）进行血清检测鉴定技术的研究。试验中制备了抗Ｃｆ的血清，应用抗００２０，０２３７，０２３８菌株的抗血清及其ＦＩＴＣ标记的抗体进行间接和直接免疫荧光染色试验（ＩＦ／ＩＦ）。通过对１９个Ｃｆ菌株和其它６个属１４个种的植物病原细菌２０个菌株的测定，结果发现约５０％的Ｃｆ菌株为强阳性反应，且与Ｃｆ种下致病变种也有强阳性交叉反应。由于单个血清检测易产生假阴性反应，故将三种血清１∶１∶１混合后进行ＩＦ试验，结果表明与所有的Ｃｆ菌株反应，且与Ｒｆａ和Ｃｍｔ有弱阳性反应。对含１０４～１０７ｃｆｕ／ｍｌ细菌及３０ｇ种子含１粒人工接种种子的种子抽提液均能检测到典型的阳性细胞，血清检测的灵敏度为４．５×１０４ｃｆｕ／ｍｌ，可用于种子的检测。本研究还进行了初步的免疫荧光菌落染色（ＩＦＣ）试验     

春麦田除草剂的应用与杂草群落演替

作者采用定点定位试验,对春麦田除草剂应用与杂草群落演替趋势进行研究。结果表明:在杂草群落多样性麦田,小麦连作并分别连续5年施用同一种除草剂,原杂草群落中占优势的靶标杂草得以控制,而非靶标杂草和抗、耐药性杂草因失去竞争和制约对象而猖獗发展,发生量较原来增加几倍至几十倍,并形成优势种群,对小麦造成新的更严重的危害。一种除草剂在同田块连续施用4年,由于杂草群落演替,抗、耐药杂草兴起,除草效果显著下降而失去其使用意义。作者提出除草剂配套使用、轮用、混用等措施,并配合以合理的轮作制度,以减轻杂草群落长期受到单一的定向选择性压力。     

利用微卫星标记分析贵州5个地方鸡品种遗传多样性

通过选用30个多态性较好的微卫星标记,检测了贵州省5个地方鸡品种:竹乡鸡、威宁鸡、黔东南小香鸡、高脚鸡、乌蒙乌骨鸡的遗传多样性。计算了各群体的平均遗传杂合度(H)、多态信息含量(PIC)和群体间的DA遗传距离。结果表明:在5个品种中,杂合度最低的是高脚鸡,为0.501,杂合度最高的是竹乡鸡,为0.673,因此贵州各地方鸡品种的杂合度相差较大,据分析可能是由于交通闭塞,形成了家禽品种的多种多型,而且杂合度的高低与PIC值的大小体现了较高的一致性;用UPGMA法进行聚类分析,结果6个鸡品种被聚为3类:竹乡鸡、黔东南小香鸡和威宁鸡聚为一类,乌蒙乌骨鸡自聚为一类;高脚鸡独自聚为一类。这与几个鸡品种的来源、分化、选育历史及地理分布是一致的。     

Stem cell factor supports migration in canine mesenchymal stem cells

Adult Mesenchymal Stem Cells (MSC) are cells that can be defined as multipotent cells able to differentiate into diverse lineages, under appropriate conditions. These cells have been widely used in regenerative medicine, both in preclinical and clinical settings. Initially discovered in bone marrow, MSC can now be isolated from a wide spectrum of adult and foetal tissues. Studies to evaluate the therapeutic potential of these cells are based on their ability to arrive to damaged tissues. In this paper we have done a comparative study analyzing proliferation, surface markers and OCT4, SOX9, RUNX2, PPARG genes expression in MSC cells from Bone marrow (BMMSC) and Adipose tissue (ASC). We also analyzed the role of Stem Cell Factor (SCF) on MSC proliferation and on ASCs metalloproteinases MMP-2, MMP-9 secretion. Healthy dogs were used as BMMSC donors, and ASC were collected from omentum during elective ovariohysterectomy surgery. Both cell types were cultured in IMDM medium with or without SCF, 10% Dog Serum (DS), and incubated at 38 °C with 5% CO2. Growth of BMMSCs and ASCs was exponential until 25–30 days. Flow citometry of MSCs revealed positive results for CD90 and negative for CD34, CD45 and MCH-II. Genes were evaluated by RT-PCR and metalloproteinases by zymografy. Our findings indicate morphological and immunological similarities as well as expression of genes from both origins on analyzed cells. Furthermore, SCF did not affect proliferation of MSCs, however it up-regulated MMP-2 and MMP-9 secretion in ASCs. These results suggest that metalloproteinases are possibly essential molecules pivoting migration.     

Contagious bovine pleuropneumonia within the 19th century miasmatic landscape

When contagious bovine pleuropneumonia (CBPP) was first detected on a farm north of Melbourne, at Bundoora, in 1858, the predominant theory of miasma was being challenged by contagionist theories of disease transmission. This well‐documented case was recorded during a period of change in the scientific assessment of disease and therefore affords an exploration of what aspects of the landscape were considered important for livestock health at the time. Although the introduction, vaccination programs and eventual eradication of CBPP on mainland Australia has been well explored, scholars have neglected this aspect of the disease's history. By comparing 19th century records of farmland with how the site appears today, it is also possible to highlight the limited information provided by contemporary texts, while at the same time developing an appreciation of the ways in which the perception of the rural landscape has changed. This differing perception has implications for the utilisation of these sources for veterinary and environmental historians seeking to understand the mid‐19th century agricultural landscape and how it relates to animal health.     

Altitude effects on technology and productivity of small bovine farms (milk meat) in Veracruz (Gulf of Mexico)

The dual-purpose bovine system represents 98.4% of the bovine livestock of Veracruz, the main cattle-producing state of Mexico. This system supplies calves to meat companies, a sector in which Veracruz has been the national leader in the last decade. The objective of the present study was to analyze the effect of the altitudinal zonation of farms on livestock technology and productivity in a microbasin of the Gulf of Mexico where small farms predominate. Structured interviews were applied to producers located in three altitudinal zones (at average altitudes of 50, 140, and 450 m, respectively, for lower, middle, and upper zones). Sample size was 135 farms having similar land surface (within a range of 15–22 ha). The results indicated multiple differences among farms located in the three zones. Farms in the middle and lower zones presented higher productive indicators than those in the upper zone. Differences in herd structure and management resulted in important differences in productivity, income, and profits in milk and calf production. We concluded from this study that altitudinal zonation in Veracruz had a clear effect on the differentiation of small farms, which are representative of dual-purpose cattle. The upper zone performs cattle activity under conditions with greater disadvantages in the analyzed region.     

生物质液化油分级产物的分离和综合利用研究

以浓硫酸为催化剂,采用甲醇-甘油复合溶剂,在高温高压的条件下对竹屑、杨木、桉木和松木进行液化,并且对液化产物进行了中和、过滤和旋转蒸发等一系列分级处理,并对液化固体残渣和气体产物进行分析。主要研究了以竹屑为原料的液化油的分级产物的组成及成分,研究结果表明:竹屑经甲醇-甘油液化,产物经过分级处理得到的主要产物为杂多酚、多糖苷和乙酰丙酸甲酯。多糖苷相主要含有多糖苷和未反应的甘油及其甘油聚合物,其中多糖苷主要为六元环吡喃糖苷,约占41.81%,甘油及其聚合物占47.27%;杂多酚相主要含有乙酰丙酸酯、杂多酚和甘油等化合物,其中甘油及其聚合物占38.04%,杂多酚相物质为难溶于水的焦油相的相对分子质量大的物质,约占杂多酚相的38.41%,并且杂多酚相的相对分子质量主要集中在990左右。     

后备公猪的科学选育与利用

后备公猪的科学选育及利用直接影响猪场制种效果和经济效益,同时也能体现规模化猪场的制种技术与水平。文章针对后备公猪选育的基本环节和操作要点,从如何选种选育、科学饲养管理、合理配种利用等方面进行系统阐述,为规模化猪场后备公猪生产提供技术指导和参考依据。