地衣芽孢杆菌复合桑叶提取物对虾夷扇贝的益生作用

Health-Promoting Effects of the Bacillus licheniformis and Mulberry Leaf Extracts Compound Preparations on the Yesso Scallop Patinopecten yessoensis

为探明地衣芽孢杆菌复合桑叶提取物对虾夷扇贝的益生作用,试验共设4个投喂组:对照组中虾夷扇贝投喂基础饲料,地衣芽孢杆菌添加组中投喂添加地衣芽孢杆菌的基础饲料,桑叶添加组中投喂添加桑叶提取物的基础饲料,联合添加组中投喂同时添加地衣芽孢杆菌、桑叶提取物2种物质的基础饲料。投喂试验共持续30 d,每10 d取样测定虾夷扇贝的消化酶和免疫酶活性。投喂试验结束后,通过注射哈维氏弧菌的方式对各组虾夷扇贝进行攻毒试验。投喂试验结果显示,联合添加组虾夷扇贝的消化酶及免疫酶活性最高,而对照组最低。表明联合添加组虾夷扇贝的消化能力、磷酸酶响应能力以及抗氧化能力明显高于其他处理组。攻毒试验结果显示:联合添加组虾夷扇贝的累积死亡率最低,对照组虾夷扇贝的累积死亡率最高,地衣芽孢杆菌添加组和桑叶添加组虾夷扇贝的累积死亡率差异不显著;联合添加组虾夷扇贝消化道中弧菌最少,对照组虾夷扇贝消化道中弧菌最多,联合添加组虾夷扇贝对弧菌的抑制效果更明显。试验结果表明,地衣芽孢杆菌与桑叶提取物联合施用时协同增效,对虾夷扇贝的益生作用更明显。

This study was conducted to investigate the health-promoting effects of the Bacillus licheniformis and mulberry leaf extracts compound preparations on the Yesso scallop Patinopecten yessoensis.Yesso scallops were divided into different groups and fed with the basal diets(CK group),basal diets supplemented with B.licheniformis(B.licheniformis treatment group),basal diets supplemented with mulberry leaf extracts(mulberry leaf extracts treatment group),or both of the two(combination treatment group).During the 30-day feeding period,the activities of digestive and immune-related enzymes were determined every ten days respectively.The results suggested that the scallops fed with supplementary diets of B.licheniformis and mulberry leaf extracts in combination produced the maximum digestive and immune activities,while the minimum values occurred in the control group.Dietary B.licheniformis and mulberry leaf extracts in combination might be more capable of improving nutrient digestion,sharpening responses to phosphatase and promoting the antioxidant abilities.The results of the challenge experiment showed that the cumulative mortality rate was the lowest in the combination treatment group,while the highest mortality occurred in the control group.No significant differences were observed between the B.licheniformis treatment and mulberry leaf extracts treatment groups.Furthermore,the combination treatment group showed the lowest counts of Vibrio,while the maximum values occurred in the control group,suqqesting that the combination treatment group could be more efficient at eliminating Vibrio in digestive tracts compared with others.These data collectively confirmed that a synergistic system was produced when subject to dietary supplementation of B.licheniformis and mulberry leaf extracts in combination,leading to more obvious health-promoting effects.