船舶噪声声压级对大黄鱼幼鱼游泳、摄食行为及免疫生理指标的影响

通过录制大黄鱼(Larimichthys crocea)产卵场附近船舶航行时的噪声,并以此为刺激源,以大黄鱼幼鱼为实验对象,研究了船舶噪声声压级对大黄鱼幼鱼游泳、摄食行为及免疫生理指标的影响。研究发现,当噪声声压级<60 dB时,幼鱼趋避游泳行为不强烈;但随着声压级增大,开始呈现出不同强度的趋避行为,依次表现出:游泳速度加快、鱼与鱼之间及鱼与桶壁之间发生碰撞、瞬间反应无序、跳跃等行为;当声压级>200 dB时,刺激2 min后就出现了死亡个体。在120 dB和150 dB短期单次和多次刺激下,幼鱼血浆中的皮质醇、血糖、血红蛋白和乳酸这4个与应激相关的生理指标均显著上升,其中皮质醇、血糖和乳酸上升幅度尤为明显。另外,皮质醇单次刺激后即达到峰值,而多次刺激后反而较单次刺激有所下降;血糖、血红蛋白和乳酸则具有累加效益,多次刺激要高于单次刺激。在120 dB长期(30 d)刺激下,幼鱼生长明显减缓,血浆中部分免疫指标(免疫球蛋白M,干扰素-α,白介素-1β和肿瘤坏死因子-α)明显降低,肠道菌群也发生显著变化,突出表现为部分益生菌如芽孢杆菌、乳杆菌等相对丰度明显降低。摄食行为影响方面,研究发现幼鱼能准确识别噪声源的位置,并具有一定的记忆性。研究结果揭示了船舶噪声对大黄鱼幼鱼的危害,可为今后制定大黄鱼产卵场的保护措施提供数据支撑。

Effects of ship noise pressure level on swimming,feeding behaviors and immuno-physiological indicators of Larimichthys crocea juveniles

The effects of ship noises on swimming,feeding behaviors and immuno-physiological indicators of cultured Larimichthys crocea juvenilesbody length:(10.5±0.8)cm]was carried out.The results showed that when the noise intensity was less than 60 dB,the avoiding swimming behavior of juveniles was not obvious;however,with the increase of noise intensity,the avoiding behavior became increasingly intense.Specific behaviors included faster swimming,collisions between fish,between fish and barrel wall,slow and disordered reaction,and even jumping reaction.When the noise intensity was more than 200 dB,dead individuals appeared after stimulation for 2 minutes.Cortisol,blood glucose,hemoglobin and lactic acid in the plasma of juveniles increased in varying degrees under 120 dB and 150 dB short-term single and multiple stimulations.More specifically,cortisol reached its peak value after a single stimulation,but decreased after multiple stimulations;however,blood glucose,hemoglobin and lactic acid showed cumulative effects,which were higher after multiple stimulations than that after a single stimulation.While for long-term stimulation(120 dB for 30 days),the growth of juveniles slowed down significantly,and immune indicators of immunoglobulin M,interferon-α,interleukin-1βand tumor necrosis factor-αin plasma were also significantly reduced.In addition,the intestinal microbiota of stressed juveniles also changed greatly compared with those of unstressed juveniles,especially for some probiotics,such as Bacillus and Lactobacillus,which were significantly deficient in the stressed juveniles.In terms of the effects on feeding behavior,the results found that juveniles could accurately identify noise sources and had a certain degree of memory.The findings reveal the harmfulness of ship noise to Larimichthys crocea juveniles,and also provide data support for future development of protection measures for spawning grounds of Larimichthys crocea.