植物提取物对犊牛致病菌的体外抑菌效果研究

The Antibacterial Effect of Plant Extracts on Calf Pathogenic Bacteria in Vitro

犊牛健康对奶牛养殖业发展和经济效益提升至关重要。植物提取物作为饲料添加剂具有促生长、抑菌和提高免疫力的作用,改善动物的健康。试验探究了黄酮类、生物碱类、精油、苷类、有机酸植物提取物对犊牛腹泻分离菌的体外抑菌效果。结果表明:(1)茶多酚对牛大肠杆菌、牛大肠杆菌K99、牛沙门氏菌和CVCC215、肠炎沙门氏菌的最小抑菌浓度(MIC)均为1 mg/mL;盐酸小檗碱对牛大肠杆菌、牛大肠杆菌K99和CVCC215的MIC分别为16、16 mg/mL和1 mg/mL;绿原酸对牛大肠杆菌、牛大肠杆菌K99和CVCC215的MIC均为16 mg/mL,对牛沙门氏菌和肠炎沙门氏菌的MIC均为32 mg/mL;(2)茶多酚对牛大肠杆菌、牛大肠杆菌K99、牛沙门氏菌和CVCC215、肠炎沙门氏菌的最小杀菌浓度(MBC)分别为1、1、2 mg/mL和2、2 mg/mL;盐酸小檗碱对牛大肠杆菌、牛大肠杆菌K99和CVCC215的MBC分别为16、16 mg/mL和2 mg/mL;绿原酸对牛大肠杆菌、牛大肠杆菌K99、牛沙门氏菌和CVCC215、肠炎沙门氏菌的MBC均为32 mg/mL;(3)茶多酚和盐酸小檗碱联合使用对牛大肠杆菌、牛大肠杆菌K99和CVCC215抑菌效果具有叠加功效。综上所述,茶多酚和绿原酸对牛大肠杆菌和沙门氏菌均具有一定的抑制作用,盐酸小檗碱对牛大肠杆菌具有一定的抑制作用,对沙门氏菌没有抑制作用;联合使用茶多酚和盐酸小檗碱对牛大肠杆菌的抑制效果具有叠加功效。

The health of the calves is vital important to the development and economic benefits of the dairy farming industry. As a feed additive, plant extracts can promote growth, inhibit bacteria and enhance immunity, and eventually improve animal health. The antibacterial effects of flavonoids, alkaloids,essential oils, glycosides, and organic acid plant extracts on calf diarrhea isolates in vitro were explored in the article. The results showed that:(1) The minimum inhibitory concentration(MIC) of tea polyphenols against bovine E. coli, bovine E. coli K99, bovine Salmonella and CVCC215, and Salmonella enteritidis were all 1 mg/mL;the MIC of berberine hydrochloride on bovine E. coli, bovine E. coli K99 and CVCC215 were 16, 16 mg/mL, and 1 mg/mL respectively;the MIC of chlorogenic acid for bovine E. coli, bovine E. coli K99 and CVCC215 were all 16 mg/mL, and the MIC for bovine Salmonella and Salmonella enteritidis were both 32 mg/mL;(2) The minimum bactericidal concentration(MBC) of tea polyphenols against bovine E. coli, vovine E. coli K99, bovine Salmonella and CVCC215, and Salmonella enteritidis were respectively 1, 1, 2, 2 mg/mL, and 2 mg/mL;the MBC of berber-ine against bovine E. coli, bovine E. coli K99 andCVCC215 were 16, 16 mg/m L and 2 mg/m L, re-spectively;the MBC of chlorogenic acid againstbovine E. coli, bovine E. coli K99, bovine Salmonella, CVCC215 and Salmonella enteritidis were32 mg/mL;(3) The combined use of tea polyphenols and berberine hydrochloride had an additive effect on bovine E. coli, bovine E. coli K99 andCVCC215. In summary, tea polyphenols and chlorogenic acid had a certain inhibitory effect on bovine E.coli and Salmonella. Berberine hydrochloride had a certain inhibitory effect on bovine E. coli, but had noinhibitory effect on Salmonella;the combination of tea polyphenols and berberine hydrochloride had anadditive effect on the inhibitory of bovine E. coli.