中文摘要：

在实验室条件下，探讨了一种复合乳酸菌拌饲口服后对草鱼（Ctenopharyngodonidellus）的安全性评价，同时进行了复合乳酸菌对草鱼肠炎病的预防试验和治疗试验。复合乳酸菌按2％‰、10‰、20‰、30‰、40‰的添加量拌饲投喂草鱼进行肠炎病的预防试验。结果显示：与阳性对照组比，试验组攻毒后的平均死亡率分别为36．7％、41．7％、41．7％、40．0％、38．3％，预防保护率分别为63．3％、58．3％、58．3％、60．0％、61．7％。草鱼攻毒后投喂添加量分别为2‰、4‰、6‰、8‰、10‰的复合乳酸菌饲料进行肠炎病的治疗试验。结果显示：与阳性对照组相比，试验组平均死亡率分别为93．3％、91．7％、96．7％、95％、95％，治疗保护率分别为6．7％、8．3％、3．3％、5．0％、5．0％。由试验结果可知：（1）试验期内复合乳酸菌对试验草鱼无不良影响，具有安全性。（2）复合乳酸菌对草鱼肠炎有一定的预防效果，治疗效果不明显，但能推迟肠炎的发病时间和减少试验鱼的死亡数。（3）在草鱼养殖的临床试验中，试验组使用复合乳酸菌后，水体中的氨氮、亚硝酸盐、硫化氢等物质含量下降，溶氧量和水体透明度增加。

英文摘要：

The present study was to evaluate the safety of muhiple-lactobacillus used in Grass carp （Cetenpharyngodon idellus ）by oral administration. Meanwhile, the multiple-lactobacillus was used for prevention and treatment tests of Grass carp Baterial enterritis. Five experimental diets were formulated in different muhiple-laetohaeillus levels （2‰, 10‰, 20‰, 30‰, 40‰） for prevention tests of Grass carp Baterial enterritis,and the average mortality rate were 36.7% , 41.7% , 41.7% , 40.0% , 38.3% , the protection rate were 63.3% , 58. 3% , 58. 3% , 60. 00/0 , 61. 7%. Same to the prevention tests, five experimental diets were formulated in different muhiple-lactobacillus levels （2‰, 4‰, 6‰, 8‰,10‰） for treatment tests. The average mortality rate were 93.3% ,91.7% ,96.7% ,95% ,95% ,the protection rate were 6.7% ,8.3% ,3.3% ,5.0% ,5.0%. The results showed that： （1）the muhiple-laetobacillus had no harmful effects on Grass carp （ Ctenopharyngoden idellus ） ; （ 2 ） the multiple-lactobacillus had some preventive effects on Grass carp baterial enteritis, while the treatment effect was not obvious, it just delayed the onset time of the disease and reduced mortality rate of the test group ; （ 3 ） as the content of NO2-N reduced, the content of NH3- N and S2- as harmful substance in water reduced effectively, the content of dissolved oxygen, water transparency increased after using the muhiple-lactobacillus.