Institute of Zoology, National Taiwan University, Taipei 106, Taiwan, ROC.
Fish Shellfish Immunol. 2010 May-Jun;28(5-6):837-44. doi: 10.1016/j.fsi.2010.01.012. Epub 2010 Feb 6.
In this study, the probiotic, Bacillus subtilis E20, isolated from the human health food, natto, was used for white shrimp, Litopenaeus vannamei, larvae breeding to improve the larval survival rate and development by adding probiotic to the rearing water at (control), 10(8), and 10(9) cfu L(-1) salt water once every 3 days during the 14 days of breeding experiment. Thereafter, stress tolerance and immune status of postlarvae were evaluated. Shrimp larval development was significantly accelerated after adding the probiotic to the larval rearing water at a level of 10(9) cfu L(-1). The survival rate of larvae was significantly higher in the treatment with 10(9) cfu L(-1) compared to the control and the treatment with 10(8) cfu L(-1) after all larvae had metamorphosed to postlarvae. Adding the probiotic to the shrimp larvae rearing water produced a weak inhibition of bacterial growth by an analysis of the total bacterial count and presumptive Vibrio count. For stress tests, no postlarvae died when they were reared in water in which the temperature was decreased from 30 to 2 degrees C at a rate of 0.1 degrees C min(-1). Postlarvae had significantly lower cumulate mortality in the treatments with 10(8) and 10(9) cfu L(-1) compared to the control when they were suddenly exposed to fresh water and 60 per thousand salt water. A significant decrease in the cumulative mortality of postlarvae treated with the probiotic at a level of 10(9) cfu L(-1) was recorded after the sudden transfer to 300 mg L(-1) nitrite-N compared to the control and treatment with 10(8) cfu L(-1). The analysis of immune-related gene expressions showed that the gene expression of prophenoloxidase I, prophenoloxidase II, and lysozyme of larvae were significantly increased after being reared in probiotic-containing water at the levels of 10(8) and 10(9) cfu L(-1). However, no significant difference in serine proteinase or glutathione peroxidase gene expressions was recorded in this study. It is therefore suggested that 10(9) cfu L(-1) of probiotic, B. subtilis E20 adding to rearing water for shrimp larva breeding.
在这项研究中，从人类保健品纳豆中分离出的益生菌枯草芽孢杆菌 E20 被用于白虾凡纳滨对虾幼虫养殖，通过在养殖水中添加益生菌来提高幼虫的存活率和发育速度，在 14 天的养殖实验中，每 3 天用 10(8)和 10(9)cfu/L(-1)盐水添加一次益生菌。此后，评估了幼虾的应激耐受力和免疫状态。在幼虫养殖水中添加益生菌至 10(9)cfu/L(-1)水平后，虾幼体发育明显加快。与对照组和 10(8)cfu/L(-1)处理组相比，在所有幼虫变态为幼虾后，10(9)cfu/L(-1)处理组的幼虫存活率显著更高。在养殖水中添加益生菌会导致总细菌计数和推定弧菌计数的细菌生长受到微弱抑制。对于应激测试，当水温以 0.1°C/min(-1)的速度从 30°C降至 2°C时，在养殖水中的幼虾不会死亡。与对照组相比，在突然暴露于淡水和 60/千盐水中时，10(8)和 10(9)cfu/L(-1)处理组的幼虾累积死亡率显著降低。与对照组和 10(8)cfu/L(-1)处理组相比，在突然转移到 300mg/L(-1)亚硝酸盐-N时，用 10(9)cfu/L(-1)益生菌处理的幼虾的累积死亡率显著降低。分析免疫相关基因表达显示，在用 10(8)和 10(9)cfu/L(-1)益生菌水平养殖的幼虫中，原酚氧化酶 I、原酚氧化酶 II 和溶菌酶的基因表达显著增加。然而，在本研究中未记录到丝氨酸蛋白酶或谷胱甘肽过氧化物酶基因表达的显著差异。因此，建议在虾苗养殖中，将 10(9)cfu/L(-1)益生菌枯草芽孢杆菌 E20 添加到养殖水中。
