抗菌肽在断奶仔猪生产中的应用研究

抗菌肽因具有抗菌谱广,无耐药、无残留,对正常体细胞无毒性等特点,在畜牧业中有望成为替代抗生素的新一代抗菌添加剂.本试验旨在探究抗菌肽对断奶仔猪生产性能、腹泻、抵抗力、经济效益等的影响,以期为进一步使用和推广抗菌肽提供依据.     

饮水饲喂天蚕素抗菌肽对肉鸡生产性能的影响

抗菌肽广泛分布于动植物和微生物中,它们相对分子质量小、水溶性好、热稳定性较高、无免疫原性且抗菌谱广,同时对真菌、肿瘤和病毒等也具有抑制作用,可作为传统抗生素的替代品,是一种有发展潜力的新型抗菌促长剂.前人对抗菌肽的研究主要集中在分离纯化、鉴定及抗微生物活性等方面,关于抗菌肽对动物生长性能的影响研究较少.     

绿色饲料添加剂抗菌肽研究进展

抗菌肽是哺乳动物防御体系的一个重要组成部分,具有分子量小、热稳定性好、无免疫原性、抗菌谱广等特点,对畜禽具有促生长、保健和治疗疾病的功能,且无毒副作用、无残留。就抗菌肽的特性及其在饲料中添加的最新研究和应用概况进行了综述,以期为抗菌肽在畜牧业中的应用提供参考。     

抗菌肽在畜牧业中的应用研究

抗菌肽是生物体抵御外源性病原微生物入侵而产生的一类小分子多肽，是动物宿主先天件非特异防御体系的一个重要组成部分。抗菌肽是阳离子型活性肽．具有分子量小、热稳定性好、水溶性好，无免疫原性，抗菌谱广且抗菌机理独特等优点，对畜禽具有促生长、保健和治疗疾病等功能，且无毒副作用、无残留、无致细菌耐药性。利用抗菌肽替代传统抗生素，对提高畜产品品质、推动绿色畜牧业的发展有着非常重要的意义。可通过生物工程的技术方法大量生产抗菌肽，使之成为新一代肽类抗菌药的来源。     

昆虫抗菌肽的抗菌效应及在畜牧生产中的应用前景

 昆虫抗菌肽是一类具有免疫效应的小分子多肽,它具有热稳定、抗菌谱广、无免疫原性、作用机制独特等特性,是昆虫能够抵御自然界中有害微生物侵染的重要因素。论文针对畜牧业生产,从昆虫抗菌肽分类、生物活性及作用机理等几个方面综述了昆虫抗菌肽的研究现状及其应用前景。     

奶牛乳房炎的治疗(三)

上接2012年第6期(总160期)疾病诊疗栏目4.4.6抗菌肽抗菌肽是生物体内存在的一种天然抗菌活性物质,与传统的抗生素相比具有分子量小、抗菌谱广、热稳定性好、无免疫原性、抗菌机理独特的优点。抗菌肽对粪肠球菌、葡萄球菌类、牛链球菌抑制作用较强,热稳定和水溶性好,对细菌、真菌     

抗菌肽研究进展及其在饲料中的应用

抗菌肽（anti—bacterial peptides）,又称抗微生物肽（peptide antibiotics）,是生物体在抵抗病原微生物的防御反应过程中产生的一种具有抗微生物功能的小分子多肽,它们多为1345个氨基酸组成的短肽（肖建光等,2005;Bulet等,2004）。抗菌肽广泛存在于植物、细菌、动物体内,是生物先天性免疫的重要效应分子。抗菌肽除具有广谱的抗菌活性外,还具有抗原虫、抗真菌、抗病毒和抑制或杀伤肿瘤细胞等作用。动物抗菌肽与青霉素等传统抗生素作用机制完全不同,病原菌不易产生对抗菌肽的耐药性。此外,抗菌肽一般情况下只作用于原核细胞和发生病变的真核细胞,而对正常的真核细胞无影响。     

天蚕素抗菌肽的优势及应用新进展

抗菌肽是进化上高度保守、普遍存在的天然免疫系统因子,具有广谱抗菌、抗病毒、抗肿瘤等多种生物学活性,且不易形成耐药性和药物残留。天蚕素抗菌肽是最早被分离出的昆虫类抗菌肽,也是迄今为止研究的最为透彻的一类抗菌肽。研究表明,与天然抗菌肽相比,经过人工改造的杂合抗菌肽比天然抗菌肽具有稳定性好、抗菌谱广、活性更高等优点。文章对天蚕素抗菌肽的优势及其在畜牧生产中的应用新进展进行了综述。     

哺乳动物抗菌肽及其在畜牧生产上的应用前景

抗菌肽是阳离子型活性肽 ,是哺乳动物防御体系的一个重要组成部分 ,具有分子量小 ,热稳定性好 ,无免疫原性 ,抗菌谱广等特点 ,通过改变细菌细胞膜的通透性而发挥抗菌作用 ,这不同于抗生素通过阻断大分子生物合成的作用机理 ,因而致病菌不易对其产生耐药性。本文就几种哺乳动物抗菌肽特性、抗菌机理、基因表达及其研究展望和存在问题进行了综述。     

天蚕素抗菌肽CAD研究进展及其在畜牧生产中的应用

抗菌肽是进化上高度保守、普遍存在的天然免疫系统因子,具有广谱抗菌、抗病毒、抗肿瘤等多种生物学活性,且不易形成耐药性和药物残留。天蚕素抗菌肽是最早被分离出的昆虫类抗菌肽,也是迄今为止研究最为透彻的一类抗菌肽。研究表明,经过人工改造的杂合抗菌肽比天然抗菌肽具有稳定性好、抗菌谱广、活性高等优点。文章对天蚕素抗菌肽CAD的研究进展及其在畜牧生产中的应用进行了综述,以为其应用提供参考。     

抗菌肽在动物生产上的应用

抗菌肽是一类对微生物有抑制作用的多肽,广泛存在于自然界中.抗菌肽具有抗细菌、真菌、病毒、原虫等多种功效,且无残留、无致微生物耐药性.抗菌肽在动物生产上已广泛使用,其优良特性有望取代抗生素.本文总结了抗菌肽的来源、功效及在动物生产上的应用,阐述了抗菌肽在生产和应用存在的主要问题.     

Antimicrobial use in the treatment of calf diarrhea

Calves with diarrhea often have small intestinal overgrowth with Escherichia coli bacteria, regardless of the inciting cause for the diarrhea, and 30% of systemically ill calves with diarrhea have bacteremia, predominantly because of E coli. Antimicrobial treatment of diarrheic calves should therefore be focused against E coli in the small intestine and blood, the 2 sites of infection. Fecal bacterial culture and antimicrobial susceptibility testing is not recommended in calves with diarrhea because fecal bacterial populations do not accurately reflect small intestinal or blood bacterial populations and because the break points for susceptibility test results have not been validated. Antimicrobial efficacy is therefore best evaluated by the clinical response of a number of calves to treatment, with calves randomly assigned to treatment groups. Amoxicillin, chlortetracycline, neomycin, oxytetracycline, streptomycin, sulfachloropyridazine, sulfamethazine, and tetracycline administered PO are currently labeled in the United States for the treatment of calf diarrhea. On the basis of published evidence for the oral administration of these antimicrobial agents, only amoxicillin can be recommended for the treatment of diarrhea. Dosage recommendations are amoxicillin trihydrate (10 mg/kg PO q12h) or amoxicillin trihydrate-clavulanate potassium (12.5 mg combined drug/kg PO q12h) for at least 3 days; the latter constitutes extra-label drug use. Parenteral administration of broad-spectrum beta-lactam antimicrobials--ceftiofur (2.2 mg/kg IM or SC q12h) and amoxicillin or ampicillin (10 mg/kg IM q12h)--or potentiated sulfonamides (25 mg/kg IV or IM q24h) is recommended for treating calves with diarrhea and systemic illness; both constitute extra-label drug use. In calves with diarrhea and no systemic illness (normal appetite for milk, no fever), it is recommended that the health of the calf be monitored and that oral or parenteral antimicrobials not be administered.     

生物抗菌肽的研究现状

抗菌肽为生物机体内天然免疫系统的重要组成部分,具有抗细菌、抗病毒、抗真菌等多种生物学活性。抗菌肽或者类似物主要通过使细胞膜通透性增大而抑制或者杀死靶细胞,具有作为新型抗生素和食品添加剂的潜在应用前景。不同抗菌肽之间、抗菌肽与传统抗生素具有协同效应,这在一定程度上拓宽了抗菌肽的应用范围。     

蚕类抗菌肽异源表达与应用研究进展

蚕类抗菌肽作为昆虫抗菌肽之一,具有分子量小、热稳定性好、抗菌谱广等优点,是新世纪抗生素最理想的替代药物。目前已经成功鉴定40个家蚕抗菌肽基因,包括Cecropins、Enbo-cins、Attacins、Moricins、Gloverins、Lebocins和Defensins。本文综述了蚕类抗菌肽的家族分类、抗菌肽应用等内容,着重阐述了蚕类抗菌肽异源表达研究。     

我国动物源细菌耐药状况、存在问题和对策

动物源细菌耐药性问题不仅关系到动物的用药安全,也与公共卫生安全密切相关,日益引起各国的关注。中国兽医药品监察所从事动物源细菌耐药性检测工作10余年,对我国动物源细菌的耐药性状况进行了系统的调查。本文从动物源细菌耐药性监测工作的重要性、我国动物源细菌的耐药性状况、存在的问题以及应对策略四个方面进行了综述,以期对我国的动物源细菌耐药性监测工作起一定的参考作用。     

家畜体内防御素多态性和表达的研究进展

抗菌肽可抵御细菌、病毒和真菌的入侵,在人类和家畜的先天性防御系统中具有重要的作用,是有望用于预防和治疗的药物,因此,抗菌肽被称为"新一代的抗生素"。抗菌肽是一个阳离子肽,其中的一个大家族就是防御素。防御素的结构中普通带有一个β-片状结构,其中包含3个分子内二硫键,可分为α-防御素、β-防御素和θ-防御素,其中β-防御素是最大的一个家族,在人类和家畜的组织内均有表达。结合已有的研究成果,作者主要对家畜体内防御素的表达、多态性及其作为健康和生产性能的遗传标记的潜在应用作一综述。     

Variation in foraging activity of Acanthochitona garnoti (Mollusca: Polyplacophora) from different habitats

Foraging activity of Acanthochitona garnoti was studied during spring and neap tides in three different habitats: an aeolian sandstone platform, a permanent high-shore rock pool (aeolian shore) and a quartzitic sandstone boulder shore. On exposed rock, A. garnoti was active only during nocturnal low tides, although some individuals were active during early morning low tides when in shade. Chitons from upper-shore pools were active during both day and night low tides. At all sites chitons foraged for longer (x? = 5.5 h) and travelled further (x? = 313 mm) during a spring tide new moon and least on a spring tide full moon (x? = 4.0 h; x? = 182 mm). Chitons on the boulder beach travelled greater distances (x? = 367 mm) during foraging than those from aeolian shores (x? = 105 mm). It is suggested that this is a result of boulder beach chitons having further to travel to find a grazing patch. Finally, A. garnoti was found to have a ranging pattern of activity on boulder shores and a homing pattern on aeolian shores.     

Innate immune defense system of the skin

Background – Antimicrobial peptides (AMPs) have a pivotal role in cutaneous innate immunity. They are present in the skin of many animals, including mammals, and are both constitutively present and inducible by infection and injury. Functions – Antimicrobial peptides exhibit antimicrobial activity against bacteria, viruses, fungi and parasites, with different potencies depending on their peptide structure. They also act as multifunctional effector molecules that influence diverse cellular processes, including cell migration, proliferation and differentiation, cytokine production, angiogenesis and wound healing. Suppressed AMP production has been associated with increased susceptibility to microbial insults and the pathogenesis of atopic dermatitis. This review highlights recent observations on the expression and role of AMPs, particularly the AMPs cathelicidin and β‐defensin, in healthy and diseased skin.     

抗菌肽抗病的研究进展

抗菌肽具有广谱杀菌,对病毒、真菌、某些肿瘤具有一定的抑制作用,抗菌肽还具有不产生耐药性,对正常细胞无毒害作用,是一种理想的生物制剂。作者综述了近些年来抗菌肽在抗细菌、病毒、真菌和癌症等方面的相关研究,并就抗菌肽在当前存在的问题和未来巨大的应用前景进行了探讨。     

Workshop report: The 2012 Antimicrobial Agents in Veterinary Medicine: exploring the consequences of antimicrobial drug use: a 3‐D approach

Antimicrobial resistance is a global challenge that impacts both human and veterinary health care. The resilience of microbes is reflected in their ability to adapt and survive in spite of our best efforts to constrain their infectious capabilities. As science advances, many of the mechanisms for microbial survival and resistance element transfer have been identified. During the 2012 meeting of Antimicrobial Agents in Veterinary Medicine (AAVM), experts provided insights on such issues as use vs. resistance, the available tools for supporting appropriate drug use, the importance of meeting the therapeutic needs within the domestic animal health care, and the requirements associated with food safety and food security. This report aims to provide a summary of the presentations and discussions occurring during the 2012 AAVM with the goal of stimulating future discussions and enhancing the opportunity to establish creative and sustainable solutions that will guarantee the availability of an effective therapeutic arsenal for veterinary species.