摘要
以苏云金芽胞杆菌无晶体突变株BMB304为受试菌株,对小鼠和雏鸡进行安全性测试,考察BMB304在鸡肠道中的存留情况,以探索利用苏云金芽胞杆菌S-层表面展示系统研制热稳定性禽用口服活菌疫苗的安全性和可行性。小鼠腹腔一次性注射1010CFUBMB304菌液1.0mL,观察14d,未发现有急性毒性反应。小鼠饮用含BMB304108CFU/mL、107CFU/mL和106CFU/mL的饮用水28d,各组小鼠精神和饮食正常,剖检未见异常变化,各剂量组小鼠体重变化、脏器系数、血常规指标及血液生化指标与对照组无显著性差异。雏鸡24h内灌服1010CFUBMB304芽胞液1.0mL,14d内未出现急性毒性反应。饲喂雏鸡含BMB304芽胞108CFU/g、107CFU/g和106CFU/g饲料28d,雏鸡精神和饮食正常,剖检未见异常变化,各剂量组的日增重与对照组差异不显著。饲喂雏鸡含BMB304芽胞106CFU/g饲料3d后,经测定,芽胞能在肠道中萌发并至少存留5d但不超过7d。研究表明,苏云金芽胞杆菌无晶体突变株BMB304对小鼠和雏鸡安全无毒,且能在鸡肠道内暂时定植,能被用于研制在细胞表面展示外源抗原并能常温长期保存的新型禽用口服疫苗。
The present paper is aimed to report its authors＇ experimental research on the way of evaluating the effect of Bacillus thuringiensis crystal negative strain BMB304 on the safety of mice and chickens. It has also studied the fate of strain BMB304 in the intestinal tract of chickens in hoping to determine the feasibility to use B. thuringiensis as a live vehicle in delivering heterologous antigen protein for veterinary vaccination. So far, there has not been found acute toxic reaction with the mice when 10^l0 CFU BMB304 vegetative cells in 1.0 mL of physiological saline were injected into them just for once. Furthermore, when mice were supplied with water mixed with BMB304 vegetative cells at the concentration of 10^8 CFU/mL, 10^7 CFU/mL and 10^6 CFU/mL, respectively, for 28 days, still no significant difference was found with the outlook, behavior, weight, and organ coefficients as well as the indexes of hematology and biochemistry in the mice in comparison with the control group. Pathological change has not been detected in the inherent organs of the mice above mentioned. There has not been found acute toxic reaction with the chickens after 10^10 CFU BMB304 spores in 1.0 mL of physiological saline were fed to them. Moreover, when chickens were fed with diet added with BMB304 spores at the concentration of 10^8 CFU/g, 10^7 CFU/g, and 10^6 CFU/g, respectively, for 28 days, neither toxic reaction nor pathological change has been detected in them. After 3 days of diet （containing 10^6 CFU BMB304 spores per grant） feeding to chickens, it could be found that the spore still persisted in the intestinal tract, the process can be found lasting over 5 days, but no more than 7 days. The above findings demonstrate that B. thuringiensis crystal negative strain BMB304 was harmless to mice and chickens, and BMB304 spores could colonize the avian intestinal tract for several days. Thus, it is suggestive that B. thuringieusis can be used to develop novel oral veterinary vaccine if delivered with spore.
出处
《安全与环境学报》
CAS
CSCD
2007年第5期12-15,共4页
Journal of Safety and Environment
基金
国家自然科学基金项目(30080036)
湖北省科技攻关重大专项(2006AA202A05)
农业微生物学国家重点实验室开放课题(AML02004)
