Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, 30100 Murcia, Spain.
Fish Shellfish Immunol. 2012 Jun;32(6):1032-40. doi: 10.1016/j.fsi.2012.02.025. Epub 2012 Mar 6.
The present work evaluates the effects of inulin and Bacillus subtilis, single or combined, on immune parameters, immune-related gene expression and protection against Photobacterium damselae subsp. piscicida in gilthead seabream (Sparus aurata). Three trials were conducted. In the first trial, different concentrations of inulin (10, 15 and 30 g kg(-1)) (as a prebiotic) were administered to determine the optimal concentration for stimulating the seabream's immune system. In the second trial, the optimum concentration of inulin (10 g kg(-1)) was combined with B. subtilis (as a probiotic). Following two and four weeks of the treatment, the main immune parameters, as well as the expression of seven immune-related genes, were measured. In the final trial, fish fed the same diet as in the second trial were challenged intraperitoneally with P. damselae subsp. piscicida (10(9) cfu g(-1)). Treatment groups for the second and third trial were control (non-supplemented diet), inulin (10 g kg(-1)), B. subtilis (10(7) cfu g(-1)) and inulin + B. subtilis (10 g kg(-1) and 10(7) cfu g(-1) respectively). Dietary administration of inulin or B. subtilis for two weeks stimulated the serum complement activity and the IgM level, as well as leucocyte phagocytic activity; furthermore, inulin stimulated leucocyte respiratory burst activity. When inulin and B. subtilis were administered together (as a synbiotic), only the serum complement activity and the IgM level increased in a statistically significant manner. Furthermore, the complement activity showed a significant increase in fish fed the three experimental diets for four weeks. The challenge experiment showed that the fish fed inulin or the synbiotic diet had non-significantly lower or significantly higher cumulative mortality, respectively, compared with the control group (non-supplemented diet). These results suggest that inulin and B. subtilis modulate the immune response of the gilthead seabream, although the combined administration increases susceptibility to infection by P. damselae subsp. piscicida.
本研究评估了菊糖和枯草芽孢杆菌单独或联合使用对真鲷（Sparus aurata）免疫参数、免疫相关基因表达和对杀鱼巴斯德氏菌（Photobacterium damselae subsp. piscicida）的保护作用。进行了三项试验。在第一项试验中，给真鲷投喂不同浓度的菊糖（10、15 和 30 g kg(-1))（作为一种益生元），以确定刺激真鲷免疫系统的最佳浓度。在第二项试验中，将最佳浓度的菊糖（10 g kg(-1))与枯草芽孢杆菌（作为一种益生菌）联合使用。治疗两周和四周后，测量了主要的免疫参数以及七种免疫相关基因的表达。在最后一项试验中，给真鲷投喂与第二项试验相同的饮食，然后通过腹腔内注射杀鱼巴斯德氏菌（Photobacterium damselae subsp. piscicida）（10(9) cfu g(-1))对其进行攻毒。第二项和第三项试验的处理组为对照组（未添加饲料）、菊糖（10 g kg(-1))、枯草芽孢杆菌（10(7) cfu g(-1))和菊糖+枯草芽孢杆菌（10 g kg(-1)和 10(7) cfu g(-1)）。两周的菊糖或枯草芽孢杆菌饮食添加刺激了血清补体活性和 IgM 水平，以及白细胞吞噬活性；此外，菊糖刺激了白细胞呼吸爆发活性。当菊糖和枯草芽孢杆菌一起添加（作为合生元）时，只有血清补体活性和 IgM 水平在统计学上显著增加。此外，在连续四周给真鲷投喂三种实验饲料后，补体活性显著增加。攻毒实验表明，与对照组（未添加饲料）相比，投喂菊糖或合生元饲料的真鲷的累积死亡率分别没有显著降低或显著升高。这些结果表明，菊糖和枯草芽孢杆菌调节真鲷的免疫反应，尽管联合使用会增加其对杀鱼巴斯德氏菌的易感性。
