摘要
为探讨禽类β-防御素13(gallinacin-13,Gal-13)作为鱼用抗生素替代品的可能性,将150尾同塘同规格尼罗罗非鱼鱼种随机等分为2组:对照组喂商品罗非鱼饵料;Gal-13组在该饵料中添加100mg/kg的Gal-13。通过观测试验鱼的生长表现及其对凡隆气单胞菌BJCP-9株的抵抗力和黏附能力,并采用cell-ELISA法体外测试Gal-13对BJCP-9黏附罗非鱼肠上皮的影响。结果显示,罗非鱼饲料中添加100mg/kgGal-13可显著提高其生长表现和抗BJCP-9感染能力(P<0.05);100μg/mL的Gal-13并不能抑制BJCP-9生长,但能在体内外抑制BJCP-9对罗非鱼肠道上皮细胞的黏附。离体模拟黏附试验表明,Gal-13在25和2.5μg/mL的低浓度下有抗黏附作用(P<0.05),提示Gal-13的抗黏附作用可能是其促进动物生长和提高罗非鱼抗凡隆气单胞菌感染的机制之一,这种抗黏附作用同离子桥和/或配体-受体连接有关,同疏水性无关。
To evaluate the feasibility of the gallinacin-13（Gal-13） as substitutes for antibiotics in fish, 150 uniform Tilapia nilotica from the same pond were assigned randomly to two groups. The tilapias in control group were fed with a commercial tilapia diet,and the tilapias in experimental group were fed with the same commercial diet supplemented with Gal-13 at 100 mg/kg. After T. nilotica were fed for 21 days,growth, disease resistance, and in vivo anti-adherence were determined by weight gain（ % ）, relative percent survival and scanning electron microscope respectively. Furthermore,the inhibitory effect of Gal-13 on adhesion of Aeromonas veronii biovar, sobria（A, vbs） strain BJCP-9 to tilapia enteric epithelia in vitro was assessed by eell-ELISA system. The Gal-13 supplemented at 100 mg/kg showed significant benefit to tilapia＇s growth and its disease resistance（P〈0.05）,and the benefit may be correlated with their interfering in the contact of bacteria with host mucosal surface. Although the tested agent did not inhibit the growth of BJCP-9 in tryptic soy broth at 100 μg/mL,Gal-13 did inhibit the adhesion of A. vbs to tilapia enteric epithe lia in vivo and in vitro. In vitro mimic assays showed that Gal-13 at low concentrations of 25μg/mL and 2.5 μg/mL had the reciprocal dose-dependent anti-adherence effect. The results indicated that the anti- adherence of the Gal-13 may be one of the mechanisms in promoting tilapia＇s growth and disease resistance to A. vbs, and the inhibition of Gal-13 may be correlated with a cation bridging and/or receptor-ligand binding,but not with hydrophobicity.
出处
《中国兽医科学》
CAS
CSCD
北大核心
2009年第5期432-436,共5页
Chinese Veterinary Science
基金
国家自然科学基金项目(30471301,30800811)
国家“十一五”高技术研究发展计划(863)项目(2006AA10Z320)
安徽农业大学引进与稳定人才基金项目(yj2006-13)
关键词
鸡β-防御素13
抗黏附
生长促进
抗感染
罗非鱼
gallinacin-13
anti-adhesion
growth promotion
anti-infection
Tilapia nilotica
