Lopes C A, Moreno G, Mahamadou I, Gomes M C, Conceição A H
Arq Inst Biol (Sao Paulo). 1979 Jul-Dec;46(3-4):87-92.
In a battery experiment, a hundred of day old broiler chicks (Hubbard) divided into ten groups, were fed for eight weeks with 50, 75 or 100mg/Kg of ration of chloramphenicol and tetraciclyne; 40, 80 or 120mg/ 2 liters of drinking water of nitrofurazone. During three months defecated feces from each bird were sampled and analysed at intervals of 15 days for the isolation of Escherichia coli strains which were submitted to the determination of drug resistance. The results showed that utilization of antimicrobial drugs selected a resistant population of Escherichia coli at 300 microgram/ml of chloramphenicol tetraciclyne and 30 microgram/ml of nitrofurazone, during the dietary period. In addition the characterization of the R factor made by conjugation against apropriated recepient strains, demonstrated it's presence in some of the tested strains has only been noted the mobilization of the tetraciclyne marker.
在一项试验中，将一百只一日龄的肉仔鸡（哈伯德品种）分成十组，用含50、75或100毫克/千克氯霉素和四环素的日粮喂养八周；用含40、80或120毫克/2升饮水的呋喃西林喂养。在三个月期间，每隔15天对每只鸡排出的粪便进行采样和分析，以分离大肠杆菌菌株，并对其进行耐药性测定。结果表明，在日粮喂养期间，使用抗菌药物在氯霉素、四环素浓度为300微克/毫升和呋喃西林浓度为30微克/毫升时筛选出了耐药性大肠杆菌群体。此外，通过与合适的受体菌株结合对R因子进行表征，证明在一些测试菌株中存在R因子，仅观察到四环素标记的转移。
