枯草芽孢杆菌对三疣梭子蟹免疫指标、生长性能及养殖水质的影响

摘要

[Objective]Effect of Bacillus subtilis on feeding performance of Portunus trituberculatus were studied to pro-vide reference for healthy culture of P. trituberculatus and promoting application of probiotics in crab culture.[Method]With P. trituberculatus being research target,experiment group(EG,adding 2×1010 CFU/g B. subtilis)and control group(CK,adding no probiotics). The experiment cycle was 28 d,during the period,growth indexes and water quality factors were measured at regular intervals. After the experiment,activities of alkaline phosphatase(AKP),acid phosphatase(ACP),peroxidase(POD), total superoxide dismutase(T-SOD)and lysozyme(LZM)in hemolymph of P. trituberculatus.[Result]B. subtilis could signifi-cantly improve AKP activity in hemolymph of P. trituberculatus(P<0.05,the same below). AKP activity gradually increased as culture time extended;ACP and POD activities gradually increased and reached the peaks on day 21(6.47U/100ml and 45.93U/ml),which were significantly higher than CK. The use of B. subtilis had no significant effects on T-SOD activity(P>0.05), but it had obvious influence on LZM content. LZM content reached the maximum on day 21(3.81 μg/mL),and then it remained at a stable level. B. subtilis did not obviously promote the growth of P. trituberculatus,but greatly improve the livability. Until the end of experiment,livability of P. trituberculatus in EG increased by 17.78%compared with CG. In addition,B. subtilis could veffectively reduce the content of NH3-N and NO2-N in cultured water,however,the effects was decreased after day 21.[concultion]Bacillus subtilis can significantly improve immunization-related enzyme activities,improve livability and re-ducing NH3-N and NO2-N contents in culture water to purify water quality.%[目的]探讨枯草芽孢杆菌对三疣梭子蟹饲养效果的影响,为开展三疣梭子蟹高效健康养殖和促进益生菌在蟹类养殖领域的推广应用提供参考依据.[方法]以三疣梭子蟹为研究对象,分别设试验组(EG,添加2×1010 CFU/g枯草芽孢杆菌)和对照组(CK,不添加任何益生菌),试验周期28 d,期间定期检测生长指标和水质因子,试验结束时测定三疣梭子蟹血淋巴中的碱性磷酸酶(AKP)、酸性磷酸酶(ACP)、过氧化物酶(POD)、总超氧化物歧化酶(T-SOD)和溶菌酶(LZM)等相关酶活力.[结果]枯草芽孢杆菌可显著提高三疣梭子蟹血淋巴中的AKP活力(P<0.05,下同),随着养殖时间推移,AKP活力逐渐升高;而ACP和POD活力均呈先升高后降低的变化趋势,于第21 d时达最高值,分别为6.47 U/100 mL和45.93 U/mL,显著高于CK组;枯草芽孢杆菌对三疣梭子蟹血淋巴T-SOD活力无显著影响(P>0.05),但对LZM含量有明显影响,也于第21 d时达最高值(3.81μg/mL),此后LZM含量维持在相对较稳定的水平.枯草芽孢杆菌对三疣梭子蟹的生长促进作用不明显,但能显著提高其存活率,至试验结束时三疣梭子蟹存活率较CK组提高了17.78%(绝对值).枯草芽孢杆菌对三疣梭子蟹养殖水体氨氮(NH3-N)和亚硝态氮(NO2--N)有显著的降低作用,但在21 d后作用效果略有下降.[结论]枯草芽孢杆菌能显著影响三疣梭子蟹免疫相关酶活力,提高其存活率,且能有效降低养殖水体中的NH3-N和NO2--N含量,进而达到净化养殖水质的效果.