兽药中氯霉素类抗生素的药理作用及用法用量

氯霉素是第一个合成的抗生素,是一种由委内瑞拉链霉菌中分离提取的广谱抗生素。对许多需氧革兰氏阳性细菌和革兰氏阴性细菌、厌氧的拟杆菌、立克次氏体、衣原体及菌质体都有抑制作用,尤其对沙门氏菌属、流感杆菌等有良好的抗菌能力。1氯霉素氯霉素也称氯胺苯醇,该药为白色或微带黄绿色针状、片状结晶或结晶性粉末,性质稳定,微溶于水。应密封保存。氯霉素为广谱抗生素,对的多数革兰氏阳性菌和阴性菌都有良好的抗菌抑制作用,而且对部分衣原体、立克次氏体和某些原虫,     

浅议乳酸菌在畜牧业中的应用及发展现状

1乳酸菌的定义 乳酸菌是一群能从可发酵性碳水化合物中产生大量乳酸的革兰氏阳性细菌的通称。乳酸杆菌有44个种,连同亚种共51个种,是革兰氏阳性、无芽孢、细长、有弯曲的杆菌。有9个属：其中5个属呈球状,如乳酸球菌迷走球菌链球菌明串珠菌和片球菌,4个属呈杆状,如肉食杆菌乳酸杆菌双歧杆菌和孢子乳酸菌。     

金黄色葡萄球菌血清5和8型的研究进展

金黄色葡萄球菌(以下简称金葡菌)是人和动物重要的接触性致病菌,从患乳腺炎的乳牛乳汁中分离到的致病菌近一半是金葡菌,这些分离菌株中 94％-100％含有荚膜多糖(CapsulaLr polysaccharide, Cp)。因此,Cp日益引起科研工作者的关注。金葡     

苏云金芽胞杆菌晶体蛋白对羊捻转血矛线虫成虫的作用

捻转血矛线虫是世界各国危害牛、羊等反刍动物的主要寄生虫之一.目前虽然有特效的化学药物驱虫,但因其具一定的副作用,寄生虫易产生耐药性,药物易在内品残留,危害人类健康.苏云金芽胞杆菌是一种革兰氏阳性细菌,它在形成芽胞的同时,在菌体一端形成一种蛋白性质伴胞晶体,它对昆虫有较高毒力,对人畜安全无毒,不污染环境,成本低,已广泛用于防治农、林、仓贮害虫和医学     

乳猪口服庆大霉素注射液中毒的诊治

硫酸庆大霉素为氨基糖苷类抗生索,对各种革兰氏阴性细菌及革兰氏阳性细菌都有良好的抗菌作用,尤其是对各种肠杆菌科细菌如大肠埃希菌、克雷伯菌属、变形杆菌属、沙门菌属、志贺菌属、肠杆菌属、沙雷菌属及铜绿假单胞菌属等有良好杀灭作用。因此,在兽医临床上常用其口服或注射来防治肠道疾病。我县某猪场因初产母猪发热,     

治疗疱疹病毒的天然中药提取物

利用该中药提取物,对细菌和病毒进行体内外抑菌和抗病毒研究。中药提取物对体外单纯疱疹病毒具有明显的抑制和直接杀灭作用;中药提取物对细菌的抑制作用非常明显,并具有广泛的杀灭作用,有良好的抗菌活性。被抑制和杀灭的细菌中既有革兰氏阳性细菌也有革兰氏阴性细菌,既有球菌也有杆菌。     

乳酸菌在水产养殖中的研究进展及其应用

乳酸菌（Lactic acid bacterium,LAB）是一群能从可发酵性碳水化合物中产生大量乳酸的革兰氏阳性细菌的通称。乳酸杆菌有44个种,连同亚种共51个种,是革兰氏阳性、无芽孢、细长、有弯曲的杆菌。有9个属：其中5个属呈球状,如乳酸球菌（lactococcus）、迷走球菌（vagococcuO、链球菌（streptococcus）、明串珠菌（leuconostoc）和片球菌（pedicoccus）;4个属呈杆状,如肉食杆（caronobacterium）、     

蘑菇生长过程中覆土内微生物群落结构的变化特征

The culturable bacterial population and phospholipid fatty acid (PLFA) profile of casing soil were investigated at different mushroom (Agaricus bisporus) cropping stages. The change in soil bacterial PLFAs was always accompanied by a change in the soil culturable bacterial population in the first flush. Comparatively higher culturable bacterial population and bacterial PLFAs were found in the casing soil at the primordia formation stage of the first flush. There was a significant increase in the ratio of fungal to bacterial PLFAs during mushroom growth. Multivariate analysis of PLFA data demonstrated that the mushroom cropping stage could considerably affect the microbial community structure of the casing soil. The bacterial population increased significantly from casing soil application to the primordia formation stage of the first flush. Casing soil application resulted in an increase in the ratio of gram-negative bacterial PLFAs to gram-positive bacterial PLFAs, suggesting that some gram-negative bacteria might play an important role in mushroom sporophore initiation.     

Soil Microbial Community Composition During Natural Recovery in the Loess Plateau, China

This study aimed to determine the characteristics of soil microbial community composition and its relationship with soil chemical properties during natural recovery in the Loess Plateau.The soil microbial community composition was analyzed by comparing the soil microbial phospholipid fatty acids（PLFAs） of eight croplands abandoned for 1,3,5,10,13,15,20,and 30 yr in the Dunshan watershed,northern Loess Plateau,China.The results showed that soil organic carbon,total nitrogen,soil microbial biomass carbon,and soil microbial biomass nitrogen significantly increased with the abandonment duration,whereas the metabolic quotient significantly decreased.The Shannon richness and Shannon evenness of PLFAs significantly increased after 10 yr of abandonment.Gram-negative,Gram-positive,bacterial,fungal,and total PLFAs linearly increased with increased abandonment duration.Redundancy analysis showed that the abandonment duration was the most important environmental factor in determining the PLFA microbial community composition.The soil microbial PLFAs changed from anteiso-to iso-,unsaturated to saturated,and short-to long-chain during natural recovery.Therefore,in the Loess Plateau,cropland abandonment for natural recovery resulted in the increase of the soil microbial PLFA biomass and microbial PLFA species and changed the microbial from chemolithotrophic to a more heterotrophic community.     

不同动物血清补体对大肠杆菌杀灭效果的观察

动物血清中的补体既是天然免疫的重要组成部分,又在获得性免疫过程中居于重要地位,在动物的抗细菌感染中居于中心枢纽地位.