配种到户几种保定方法

随着科学技术的不断创新,通讯事业飞速发展,千家万户都安上了电话,家畜繁育改良工作也由过去在繁育中心坐家配种转变为主动到农户家中服务,母畜保定就成了当前比较棘手的问题.为了解决母畜保定问题,我们采用了以下几种方法仅供参考.     

黑龙江省养蜂史概况(二)

二十世纪前半期一、意大利蜂的引入1903￣1920年,西方蜂种(主要是意蜂)及新养蜂法先传入福建、广东、香港、天津、北京等地,不久也传入黑龙江省。民国初年的养蜂情况《珠河县志》有以下记载:"民国初年,西洋蜂种及养蜂法传来以后,     

母猪产后不食的分型疗法

(一)病因类型 1.消化不良型:母猪产前精料喂的过多,或突然更换饲料,加重胃肠负担,引起消化不良.此病常发于分娩之后,体温正常,食欲不振,粪便先干后稀,有的病猪喜欢喝点成汤,有的吃点鲜块茎和生米等食物,但数量不大,严重者食欲废绝.     

国内玉米价格涨跌两难

随着年关临近，为了确保产区农民收入稳定增长，近日，政府有关部门出台了东北储备粮收购计划。在该重大利好政策拉动之下，我国部分产区玉米价格有望触底反弹，但受市场供应依然充足、需求整体依旧偏弱影响，国内玉米市场行情涨跌两难，具体分析如下：     

浅谈貉的饲养管理

1 配种准备期的管理 1.1营养供给原则 要维持本身的需要,使其肥胖度适中,外形匀称.另外,补充由于繁殖而消耗的营养物质,供给冬毛生长所需的营养物质.建议日粮标准是:10～11月份,鱼肉类10%～15%,动物副产品5%～10%,谷物70%,蔬菜10%.食盐2.5%,骨粉5%～10%,12月到明年1月份,鱼肉类20%～25%,动物副产品5%～10%,谷物'70%,蔬菜10%,酵母5%～8%,食盐2.5%,骨粉5%～10%,维生素A、B适量.给饲标准:10～11月份每只每日550～700g;12月份到明年1月份每只每日400～500g.     

主要组培花卉品种介绍

非洲菊:又名扶朗花,菊科,大丁草属,多年生草本植物;原产非洲南部,性喜温暖,阳光充足和空气流通的环境,不耐寒,忌炎热,生长适温20￣25℃,喜疏松、肥沃、排水良好且富含有机质的微酸性土壤。园艺品种花色丰富,有白、红、粉、黄等色系。兼有切花和盆花类型。彩色马蹄莲:天南星科多     

对河南桑蚕“十一·五”发展规划的几点建议

<正>河南省地处黄河中下游，蚕业生产历史悠久。建国50年以来，尤其是近20g间，经过“七·五”至“八·五”的迅速发展和“九·五”、“十·五”的稳步调整，河南蚕业生产规模基本稳定，生产水平得到提高。目前全省桑园面积1．67万hm~2，年产桑蚕茧6000t，与建国时相比，桑园面积和蚕茧产量分别增长了24倍和42．2倍，与改革开放初期的1978年相比，分别增长了2．25倍和4．18倍；蚕业深加工等综合产值达到10亿元，农民收入达5亿元，出口创汇8600多万美元。“九·五”、“十·五”期间，河南茧丝绸业保持着北方诸省(山东、陕西省除外)生产、出口主要基地和传统优势产业、出口创汇大户的地位。蚕业生产已成为不少平原和山区农民脱贫致富奔小康的支柱产业。 1 “九·五”、“十·五”实际生产情况 1．1 实际生产情况 1．1．1 生产规模保持基本稳定桑蚕生产在经历了1995年“全面下滑”桑园规模大幅度缩减后，“九·五”期间，全省蚕茧的总产和年产量也相应减少，但集中产     

缩小分组饲养的面积

在丹麦,人们已经提出一个分组饲养妊娠母猪的新观念,名叫"最佳猪栏",它把群饲设备与单独饲喂和铺有稻草、排水良好的地面结合在一起,见图1.对这种设计的研究显示,给妊娠母猪建成一个既有饲喂/休息的去处,又有一个铺垫良好的躺卧处的猪栏-所占面积总量与配备给群饲母猪的电子饲喂系统的场地所使用的面积相当.     

发现商机的14大法则

商机无论大小,从经济意义上讲一定是能由此产生利润的机会.商机表现为需求的产生与满足的方式上在时间、地点、成本、数量、对象上的不平衡状态.旧的商机消失后,新的商机又会出现.没有商机,就不会有"交易"活动.商机转化为财富,必定满足五个"合适":合适的产品或服务,合适的客户,合适的价格,合适的时间,合适的渠道.目前我们能认识的商机大致可归结为14种:     

夏秋季节怎样防治乌龟红甲病

夏秋季节龟活动较多,或运输中腹甲损伤,或池子粗糙引起磨损龟甲后而导致龟甲内局部红肿发炎,多数常见于腹甲内部有出血斑块,并向四周浸润扩散,严重时可波及整个龟甲,引起败血症而死亡.池中水质差、消毒少、水底氧气少时易产生大量单孢杆菌是引起此病的元凶.     

鲍曼不动杆菌雏鸡分离株CCGGD201101的分离、鉴定及致病性研究简

试验旨在鉴定吉林省某雏鸡孵育基地病死雏鸡组织中分离出的1株致病性菌CCGGD201101株并测定其致病性。对疑似致病菌进行生理生化试验、16S rDNA测序鉴定，并人工接种昆明鼠，测定其半数致死量，验证细菌毒力。经鉴定该菌为鲍曼不动杆菌（Acinetobacter baumannii）。以鲍曼不动杆菌CCGGD201101分离株为研究对象，并以鲍曼不动杆菌标准株（ATCC 19606）为对照，测得半数致死量，进一步证明鲍曼不动杆菌病死鸡分离株CCGGD201101具有较强致病性。     

The role of Acinetobacter baumannii as a nosocomial pathogen for dogs and cats in an intensive care unit

Acinetobacter baumannii is a nosocomial pathogen associated with high morbidity and mortality in humans. Whereas infections with strains of Acinetobacter species have been reported in various situations, the importance of A baumannii as a nosocomial pathogen in veterinary hospitals has not been studied so far. In this retrospective case series, we describe 17 dogs and 2 cats from which A baumannii had been isolated during a 21/2-year period. In 7 dogs, A baumannii induced systemic signs of illness, whereas 12 animals showed signs of local infection. In all animals with systemic infection, and in 2 with localized infection, A baumannii contributed to the death of the animal or contributed to euthanasia; the remaining 8 dogs and both cats recovered. Molecular typing of the isolates with restriction polymorphisms of ribosomal DNA provided evidence of nosocomial spread of this pathogen and for the presence of several strains of A baumannii in the hospital environment.     

Brucella: a pathogen without classic virulence genes

The first species of Brucella was isolated and characterized almost 120 years ago and recently the complete nucleotide sequences of the genomes of a number of well-characterized Brucella strains have been determined. However, compared to other bacterial pathogens relatively little is known about the factors contributing to its persistence in the host and multiplication within phagocytic cells. Also, many aspects of interaction between Brucella and their host remain unclear. Molecular characterization of intracellular survival process of Brucella is important as it will provide guidance for prevention and control. One of the features that distinguish Brucella is that they do not express classical virulence factors. Thus identification of virulence factors has been elusive and some of the identifications are putative. Disruption of putative virulence genes and studying their effect on attenuation in cell lines or mouse models is a widely used method. However, in most cases it is not apparent whether the mutated genes encode virulence factors or merely affect metabolic pathways of the pathogen. In addition, some mutations in Brucella can be compensated by redundancy or backup mechanisms. This review will examine known virulence genes (real and putative) identified to date and the mechanisms that contribute to the intracellular survival of Brucella and its ability to establish chronic infection.     

无乳链球菌毒力基因与耐药性的相关性研究进展

乳房炎是奶牛养殖业中最常见的一种疾病，会造成奶牛乳腺发炎肿胀，使产奶量大幅下降。作为一种多因素性疾病，奶牛乳房炎发病原因复杂，饲料污染、病原菌感染以及环境因素均可以导致乳房炎的发生。无乳链球菌（Streptococcus agalactiae）作为奶牛乳房炎的主要致病菌，常会造成乳腺组织的局部炎症，随着无乳链球菌分离率的增加以及抗菌药物的滥用，其对抗菌药物的耐药性逐步攀升，给临床治疗带来了一定的困难。此外，无乳链球菌能够定植于宿主体内，破坏宿主的免疫系统，而其自身毒力因子会引起宿主机体疾病的产生。随着相关研究的深入，发现毒力与耐药性本身互为关联，耐药性的增强以不同的方式影响毒力，表明了耐药性与毒力因子之间存在着一定的相关性。笔者主要回顾了国内外链球菌以及其他细菌毒力基因与耐药性之间相关性的研究进展，从无乳链球菌毒力因子及耐药性等多种角度入手，分析了无乳链球菌的毒力机制以及毒力基因，并对近5年国内不同地区无乳链球菌耐药性进行统计，从细菌种类、环境和相关机制对链球菌的毒力和耐药性之间的关系展开综述，以期为无乳链球菌所引起的临床症状筛选出合理的抗菌药物并对毒力基因与耐药性的相关性研究提供理论参考。     

Disruption of srtA gene in Streptococcus suis results in decreased interactions with endothelial cells and extracellular matrix proteins

Streptococcus suis, a major pathogen of swine, is an emerging zoonotic agent which causes meningitis and septic shock. In this study, we investigated the ability of S. suis mutant strain (SRTDeltaA) lacking the sortase A gene (srtA) to interact with host cells and extracellular matrix (ECM) proteins, as well as its virulence in a mouse infection model. We demonstrated that mutant SRTDeltaA had reduced capacity to adhere to and invade porcine brain microvascular endothelial cells compared to the wild-type strain. In addition, mutant SRTDeltaA also showed significantly less adherence to plasma fibronectin, cellular fibronectin and collagen type I. However, disruption of srtA had little effect on the virulence of S. suis in a mouse intraperitoneal model of infection. These results indicate that surface proteins anchored by sortase A are required for a normal level of bacterial binding. However, other factors may also be important for S. suis virulence and interaction with host tissues.     

Re-examination of the role of the Brucella melitensis HtrA stress response protease in virulence in pregnant goats.

Based on previously reported studies describing the experimental infection of pregnant goats with B. melitensis strain RWP5, we proposed that the HtrA protease plays an important role in the virulence of B. melitensis in its natural ruminant host. Subsequent studies, however, have shown that RWP5 is actually an htrA cycL double mutant. In order to definitively evaluate the role of the B. melitensis htrA in virulence, we constructed an authentic htrA mutant and examined this strain in pregnant goats. The findings of these studies indicate that the contribution of the htrA gene product to the virulence of B. melitensis in its natural host is not as great as was previously proposed.     

Virulence gene regulation in pathogenic Escherichia coli.

The ability to regulate gene expression throughout the course of an infection is important for the survival of a pathogen in the host. Thus, virulence gene expression responds to environmental signals in many complex ways. Frequently, global regulatory factors associated with specific regulators co-ordinate expression of virulence genes. In this review, we present well-described regulatory mechanisms used to co-ordinate the expression of virulence factors by pathogenic Escherichia coli with a relative emphasis on diseases caused by E. coli in animals. Many of the virulence-associated genes of pathogenic E. coli respond to environmental conditions. The involvement of global regulators, including housekeeping regulons and virulence regulons, specific regulators and then sensor regulatory systems involved in virulence, is described. Specific regulation mechanisms are illustrated using the regulation of genes encoding for fimbriae, curli, haemolysin and capsules as examples.     

A case of necrotizing fasciitis with septic shock in a cat caused by Acinetobacter baumannii

A 4-year-old, neutered female, domestic shorthair cat admitted to the animal hospital for recurrent constipation presumed to be due to post-traumatic injuries, went into shock with signs including fever and ataxia followed by stupor. On the fifth day of hospitalization, the cat developed severe, diffuse oedema of the ventral abdomen with multifocal to coalescing erythematous areas and small vesicle formation. The results of bacteriological cultures of liver, spleen and kidney specimens led to the diagnosis of Acinetobacter baumannii sepsis. Histopathological findings of skin samples taken during necropsy showed an extensive epidermal and dermal necrosis with septic vasculitis and numerous intralesional gram-negative bacteria. Detection of the bla(OXA-51-like) gene specific for A. baumannii by PCR, performed retrospectively on samples of the deep layers of the skin, confirmed the presence of A. baumannii also in the cutaneous lesions. To our knowledge this is the first report of a necrotizing fasciitis with septic shock in a cat caused by A. baumannii.     

Pathogenesis of and strategies for preventing Edwardsiella tarda infection in fish

Edwardsiella tarda is one of the serious fish pathogens, infecting both cultured and wild fish species. Research on edwardsiellosis has revealed that E. tarda has a broad host range and geographic distribution, and contains important virulence factors that enhance bacterial survival and pathogenesis in hosts. Although recent progress in edwardsiellosis research has enabled the development of numerous, highly effective vaccine candidates, these efforts have not been translated into a commercialized vaccine. The present review aims to provide an overview of the identification, pathology, diagnosis and virulence factors of E. tarda in fish, and describe recent strategies for developing vaccines against edwardsiellosis. The hope is that this presentation will be useful not only from the standpoint of understanding the pathogenesis of E. tarda, but also from the perspective of facilitating the development of effective vaccines.     

口蹄疫病毒前导蛋白的分子生物学研究进展

口蹄疫病毒（Foot-and-mouth disease virus ,FMDV）编码的前导蛋白,不仅是一个重要的蛋白酶,而且对于病毒来说是一个重要的毒力因子,其能够作用于宿主细胞的特异性蛋白,抵抗宿主细胞所产生的抗病毒效应。本文章简述了口蹄疫病毒前导蛋白酶的基本特性,例如前导蛋白的基因结构与病毒复制的关系,前导蛋白酶活性的具体特点,以及前导蛋白影响病毒毒力的分子机制。