Chen Po-Wen, Ho Shu-Peng, Shyu Ching-Ling, Mao Frank C
Department of Veterinary Medicine, National Chung-Hsing University Taichung, Taiwan 40227, Republic of China.
Am J Vet Res. 2004 Feb;65(2):131-7. doi: 10.2460/ajvr.2004.65.131.
To determine the antibacterial activity of bovine lactoferrin hydrolysate (bLf-lysate) alone or in combination with other antimicrobials against antimicrobial-resistant Escherichia coli strains isolated from baby pigs.
3 clinical strains of E coli were isolated from baby pigs with severe diarrhea and designated as strains 9061, 9062, and 9065.
The broth microdilution checkerboard and fractional inhibitory (or bactericidal) concentration index were used to evaluate the antibacterial effect elicited by bLf-lysate in combination with kanamycin, gentamicin, cephalothin, cefamandole, penicillin G, ampicillin, tetracycline, erythromycin, or rifampicin against the 3 strains of E coli.
The 3 strains of E coli were susceptible to gentamicin and rifampicin but highly resistant to most of the other antimicrobials tested, except for strain 9061 that was also susceptible to cephalothin but intermediately inhibited by kanamycin and cefamandole. Synergistic growth-inhibitory activity was observed between bLf-lysate and gentamicin against 1 strain of E coli (strain 9062); synergistic bactericidal activity was found between bLf-lysate and rifampicin against all 3 strains of E coli. Moreover, partial synergy was observed between bLf-lysate and kanamycin, gentamicin, cephalothin, or cefamandole against the strains of E coli, but this partial synergistic activity was mostly seen against only 1 of the strains. Little interaction between bLf-lysate and tetracycline, ampicillin, penicillin G, or erythromycin was observed against the clinical strains of E coli.
A combination of bLf-lysate and certain antimicrobials may prove clinically effective against antimicrobial-resistant strains of E coli.
确定牛乳铁蛋白水解物（bLf-水解物）单独或与其他抗菌剂联合使用时，对从仔猪分离出的耐抗菌性大肠杆菌菌株的抗菌活性。
从患有严重腹泻的仔猪中分离出3株大肠杆菌临床菌株，分别命名为9061、9062和9065菌株。
采用肉汤微量稀释棋盘法和部分抑菌（或杀菌）浓度指数，评估bLf-水解物与卡那霉素、庆大霉素、头孢噻吩、头孢孟多、青霉素G、氨苄西林、四环素、红霉素或利福平联合使用时对这3株大肠杆菌的抗菌效果。
这3株大肠杆菌对庆大霉素和利福平敏感，但对大多数其他测试抗菌剂具有高度抗性，不过9061菌株对头孢噻吩也敏感，对卡那霉素和头孢孟多呈中度抑制。bLf-水解物与庆大霉素对1株大肠杆菌（9062菌株）具有协同生长抑制活性；bLf-水解物与利福平对所有3株大肠杆菌均具有协同杀菌活性。此外，bLf-水解物与卡那霉素、庆大霉素、头孢噻吩或头孢孟多对大肠杆菌菌株具有部分协同作用，但这种部分协同活性大多仅在其中1株菌株中观察到。bLf-水解物与四环素、氨苄西林、青霉素G或红霉素对大肠杆菌临床菌株几乎没有相互作用。
bLf-水解物与某些抗菌剂联合使用可能在临床上对耐抗菌性大肠杆菌菌株有效。
