Kokosharov T
Vet Med Nauki. 1987;24(1):19-23.
Studied was the dynamic of antibiotic resistance of Escherichia coli strains as isolated from fecal samples taken from 5-day-old calves that had not been offered antibacterial means. The resistance manifested was compared to that of E. coli organisms isolated from calves that had been given antibacterial agents in the course of 36 months as well as to the resistance of E. coli strains isolated from calves at 1, 3, and 5 months of age and from dam cows in the last 12 months of the experiment. A varying period was established for receding of the signs of resistance of the strains to antibiotics--6 months for E. coli to kanamycin and furazolidone, 9 months to tetracycline, chloramphenicol, and gentamycin, and 15 months to streptomycin. Strains isolated from newborn calves on farms with no records of infection were shown to be susceptible to all antibiotics, while those isolated from calves on farms where enteritis was recorded remained polyresistant up to 36 months. No correlation was found between the antibiotic resistance of fecal E. coli strains from the dams and their calves.
研究了从未使用过抗菌药物的5日龄犊牛粪便样本中分离出的大肠杆菌菌株的抗生素耐药性动态变化。将所表现出的耐药性与在36个月期间使用过抗菌药物的犊牛分离出的大肠杆菌的耐药性进行比较，同时也与实验最后12个月中1月龄、3月龄和5月龄犊牛以及母牛分离出的大肠杆菌菌株的耐药性进行比较。确定了菌株对抗生素耐药迹象消退的不同时间段——大肠杆菌对卡那霉素和呋喃唑酮为6个月，对四环素、氯霉素和庆大霉素为9个月，对链霉素为15个月。在没有感染记录的农场中从新生犊牛分离出的菌株对所有抗生素敏感，而在记录有肠炎的农场中从犊牛分离出的菌株在36个月内仍具有多重耐药性。未发现母牛粪便中大肠杆菌菌株的抗生素耐药性与其犊牛之间存在相关性。
