A mixed culture of probiotics, one from the genus Bacillus and one lactic acid bacterium (LAB), was developed to be used as a feed additive for enhancing growth, innate immunity and disease resistance in Pangasius bocourti. From our earlier work, three probiotic Bacillus species, Bacillus siamensis B44v, Bacillus sp. B51f and Bacillus aerius B81e, and three probiotic LABs, Streptococcus lutetiensis L7c, Lactiplantibacillus paraplantarum (synonym. Lactobacillus paraplantarum) L34b-2 and Lactiplantibacillus plantarum (synonym. Lactobacillus plantarum) L42g, were selected for comparison. These bacteria, which express probiotic properties including bacteriocin-like activity against Aeromonas hydrophila, were subjected to in vivo screening in hybrid catfish (Clarias macrocephalus × Clarias gariepinus). A 30-day feed-trial followed by a challenge test in screening experiments resulted in the prominent B. aerius B81e and L. paraplantarum L34b-2 being selected. A mixture of these bacteria was added to a diet for P. bocourti. After 60-day feeding, the fish fed with mixed probiotics had weight gain, specific growth rate and feed conversion ratio improved significantly (p < 0.01) when compared to the control. Both humoral and cellular immunity were significantly higher in probiotic-fed fish. Following the 60-day feeding experiment, P. bocourti fed with the diet containing mixed probiotics had a higher survival rate than the control fish after injection with a virulent A. hydrophila. It can be concluded that a combination of B. aerius strain B81e and L. paraplantarum strain L34b-2 markedly improved growth performance, innate immunity and disease resistance of P. bocourti.

开发了一种益生菌的混合培养物，一种来自芽孢杆菌属和一种乳酸菌 (LAB)，可用作饲料添加剂，以增强鲶鱼的生长、先天免疫和抗病能力。从我们早期的工作中，三种益生菌芽孢杆菌属，暹罗芽孢杆菌B44v，芽孢杆菌属。B51f 和Bacillus aerius B81e，以及三种益生菌 LAB，Streptococcus lutetiensis L7c、Lactiplantibacillus paraplantarum（同义词。Lactobacillus paraplantarum）L34b-2 和Lactiplantibacillus plantarum（同义词。Lactobacillus plantarum）) L42g，被选中进行比较。这些细菌表现出益生菌特性，包括对嗜水气单胞菌的细菌素样活性，在杂交鲶鱼（大头鲇属（Clarias macrocephalus × Clarias gariepinus））中进行了体内筛选。经过 30 天的饲料试验，然后是筛选实验中的挑战测试，结果选择了突出的B. aerius B81e 和L. paraplantarum L34b-2。这些细菌的混合物被添加到P. bocourti的饮食中。饲喂60天后，饲喂混合益生菌的鱼体重增加、比生长率和饲料转化率显着提高（p< 0.01) 与对照相比。益生菌喂养的鱼的体液免疫和细胞免疫都显着提高。以下60天饲养试验，P. bocourti供给用含有混合益生菌具有更高的存活率比注射用强毒后的控制鱼饮食嗜水。可以得出结论，B. aerius菌株B81e 和L. paraplantarum菌株L34b-2 的组合显着提高了P. bocourti 的生长性能、先天免疫和抗病性。