Ticks on livestock in St. Lucia

Cattle, sheep, goats and horses were examined for ticks. Over 95% of Holstein cross-breeds, 28% of sheep (local mixed breeds) and 18% of goats (local mixed breeds) examined from 18 August to 4 September 1983 were infested with the southern cattle tick, Boophilus microplus Canestrini. About 90 and 17% of the horses examined were infested with the tropical horse tick, Anocentor nitens Neumann, and the tropical bont tick, Amblyomma variegatum Fabricius, respectively. The tropical bont tick was found infesting 10% of cattle in the Gros Islet area of St. Lucia. The tropical bont tick was also found associated with a severe skin disease, dermatophilosis, caused by the bacterium Dermatophilus congolensis, in 54% of the cattle infested by A. variegatum in the Gros Islet and Dauphin areas of St. Lucia.     

Ticks and hemoparasitoses of livestock in Senegal. III. The Northern Sudan area

The authors describe the results of a study on ticks and hemoparasitoses of cattle and small ruminants in the Senegalese north-sudanian area. For 15 months, 40 bovine, 40 sheep and 40 goats received a routine dipping treatment, aimed at the determination of the tick population dynamics together with an accurate localization of the preferential sites for the different species. The following parasites were collected from the animals: Hyalomma marginatum rufipes, H. truncatum, Rhipicephalus lunulatus, Rh. e. evertsi, Rh. sulcatus, Rh. senegalensis, Boophilus decoloratus. Joint studies were conducted on the hemoparasites using blood smear and splenectomy. Among bovine, Anaplasma marginale, Ehrlichia bovis, Theileria mutans, Th. velifera, Trypanosoma congolense, T. brucei and microfilariae from Setaria labiatopapillosa were observed. Babesia bigemina was observed after a splenectomy. In small ruminants, the detected infections are brought about by A. ovis, Th. ovis and T. vivax. Hematocrite value of apparently healthy animals are studied as well as the seasonal variation of this hematological factor.     

蜱MicroRNA研究进展

蜱是一类专门寄生于脊椎动物的体表寄生虫,是继蚊子之后的第二大传播媒介。它们传播多种疫病,不仅给畜牧业造成极大的经济损失,而且还引起人类发生疾病甚至死亡。MicroRNA(简称miRNA)是18nt~25nt的非编码小RNA,具有组织特异性和阶段特异性的特点。miRNA作用于靶基因的3′端非翻译区以抑制其表达或者降解mRNA,进而在后转录水平发挥着重要的生物学调控作用,如生长发育和先天性免疫等。有研究显示,miRNA可能调控幼蜱的生长发育,并对蜱虫吸血和血液消化有一定的作用。论文综述了miRNA在蜱体内的研究概况及其生物学功能的研究进展,以期为蜱的研究提供参考。     

蜱功能基因研究进展

蜱是动物体表的一类常见吸血寄生虫,能充当多种重要疾病的媒介,因此必要采取安全的免疫手段控制蜱害,从分子水平上研究蜱可能成为这种构想的最好突破口。在蜱持续吸血、存储病原等系列独特的生理活动中,相关的功能基因调节发挥着重要作用,了解这些基因的分布、种类和功能,对蜱疫苗的研制和生物制剂的开发将具有重要意义。     

蜱的生物防治研究进展

蜱是放牧家畜体表常见的一类外寄生虫,并可作为许多疾病的传播媒介,给人类健康和动物生产带来极大的威胁。在自然界中,多种病毒、细菌、真菌和线虫可寄生于蜱体并对其产生致病性,某些寄生蜂和禽类等可充当蜱的捕食者或天敌,它们在蜱的防控中均担当着重要角色。文章将以蜱的病原和天敌为重点,对蜱的生物防治研究进展进行介绍。     

新疆小海子垦区媒介蜱及其携带梨形虫种类鉴定

为探究新疆小海子垦区及周边地区媒介蜱及所携带梨形虫种类,2020年5月～7月通过形态学采集到524枚硬蜱;用梨形虫18S rRNA特异性引物对硬蜱样本进行PCR检测,并对阳性样本18S rRNA基因进行遗传进化分析.结果表明,采集的硬蜱包括小亚璃眼蜱(Hyalomma anatoricum)293只、亚洲璃眼蜱(H.a...     

石河子地区宠物犬蜱的种类鉴定及其携带布鲁氏菌的检测

为了解新疆石河子地区宠物犬体表寄生蜱的种类及蜱携带布鲁氏菌情况,本试验在形态学分类的基础上,基于线粒体基因12S rRNA和细胞色素氧化酶Ⅰ（COⅠ）对宠物犬体表采集寄生蜱进行分子生物学检测,使用DNAMAN软件比对分析序列同源性,并应用序列分析软件Mega 7.0邻接法构建蜱种系统发育进化树,分析蜱种的遗传进化关系;基于布鲁氏菌外膜蛋白Omp22基因对宠物犬体表寄生蜱进行布鲁氏菌PCR检测,确定宠物犬蜱布鲁氏菌携带情况。结果显示,宠物犬体表寄生的436只蜱的形态学与线粒体基因（12S rRNA和COⅠ）分子生物学鉴定结果一致,均为新疆优势蜱种之一——图兰扇头蜱（Rhipicephalus turanicus）。基于12S rRNA基因构建的蜱种系统发育树显示,本试验所得宠物犬体表寄生图兰扇头蜱序列与GenBank中已知图兰扇头蜱的序列聚为一大支。基于布鲁氏菌Omp22基因的巢式PCR扩增结果显示,宠物犬体表寄生图兰扇头蜱携带布鲁氏菌的阳性率为4.82%（21/436）,且同源性为100%。BLAST比对显示,本试验所得宠物犬图兰扇头蜱携带的布鲁氏菌与新疆流行株YC31（GenBank登录号：MK201679.1）、QH5（GenBank登录号：MK201678.1）、EM3（GenBank登录号：MK201677.1）和ML9（GenBank登录号：MK201676.1）的同源性均为100%。本研究通过形态学及分子生物学探讨了新疆石河子地区宠物犬体表寄生蜱的种类及携带布鲁氏菌基本情况,为宠物犬体表寄生蜱的种类及蜱传疾病的监测和控制等研究工作提供了基础资料。     

家畜泌乳生物学的研究进展

几十年来科研人员通过体内和体外试验的方法对泌乳动物的营养物质转运、调控机理以及激素的调控过程进行了大量的研究。但对动物营养、动物健康和乳成分含量之间的关系仅局限于单一日粮组分的调控,以及对其生化与代谢效果的研究。如今随着基因组学、蛋白组学及相关技术的发展,可以对以上问题进行更全面的研究。这些新技术正在为探究营养、泌乳和乳产品质量之间的相互作用提供新的、分子水平上的研究手段。文章回顾了营养对乳腺功能及其健康的作用,并对近20年家畜泌乳物学的研究热点问题加以介绍。     

养殖场的消毒管理

近几年来,在养殖业蓬勃发展的同时,畜禽疾病也在呈现区域性的频发,为了有效地控制畜禽疾病,除了利用疫苗、药物防治以外,合理地利用消毒药也是控制畜禽疾病一个很好的措施,因为消毒药可以直接对病原微生物进行杀灭.怎样算是合理利用消毒药,笔者根据实践提出几点想法.     

浅谈对畜禽养殖场的消毒

近年来,各地畜禽养殖业得到迅猛发展,取得了显著的社会效益和经济效益。众所周知,随着畜禽养殖业规模化、集约化程度的提高,畜禽养殖场疫病控制已成为养殖成败的关键。如何预防、控制和扑灭疫病,做好消毒净化工作是重点。做好消毒工作,可以提高安全系数,及时把疫病堵在门外,以及控制或扑灭疫病,保障畜禽养殖业蓬勃发展。日常工作中,有畜禽养殖场或专业户反映,他们经常做消毒工作,但效果却很差。笔者认为,行业内不少生产经营者对消毒的基本常识不清楚,往往是盲目跟从或模仿,不能进行科学消毒,致使消毒的效果不理想。如消毒效果可受消毒剂的选…     

Antimicrobial resistance in livestock

Antimicrobial resistance may become a major problem in veterinary medicine as a consequence of the intensive use and misuse of antimicrobial drugs. Related problems are now arising in human medicine, such as the appearance of multi-resistant food-borne pathogens. Product characteristics, dose, treatment interval and duration of treatment influence the selection pressure for antimicrobial drug resistance. There are theoretical, experimental and clinical indications that the emergence of de novo resistance in a pathogenic population can be prevented by minimizing the time that suboptimal drug levels are present in the infected tissue compartment. Until recently, attention has been focused on target pathogens. However, it should be kept in mind that when antimicrobial drugs are used in an individual, resistance selection mainly affects the normal body flora. In the long term, this is at least equally important as resistance selection in the target pathogens, as the horizontal transfer of resistance genes converts almost all pathogenic bacteria into potential recipients for antimicrobial resistance. Other factors contributing to the epidemiology of antimicrobial resistance are the localization and size of the microbial population, and the age, immunity and contact intensity of the host. In livestock, dynamic herd-related resistance patterns have been observed in different animal species.