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1.
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。 相似文献
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阐述了铜陵市旅游业发展现状,在对铜陵发展旅游业所具有的优势、机会、劣势及挑战因素的SWOT分析和总结的基础上,提出相应解决方法和对策。 相似文献
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In order to realize the real-time appetite-based feeding in aquaculture, a novel and practical method, based on the quantification of the spontaneous collective behaviors, was proposed in this study to assess the real-time appetite of the swimming fish in a recirculating aquaculture system. First, foreground feature points of fish school were extracted using an improved complex network. Then, covariance, a modified social force model and a kinetic energy model were used to analyze the collective behaviors of the school from perspectives of dispersion degree, interaction force and the changing magnitude of the water flow field, respectively. Finally, the quantified behavioral characteristics were integrated and used to assess the appetite of fish school. The presented method shows its good performance in the expression of the collective behaviors representing five typical appetites (0.01, 0.52, 1.28, 2.26 and 2.92), and the assessing accuracy of the appetite of the school is also maintained at a low non-match rate ((2.19 ± 0.81)% best) in the context of ten different sampling durations. 相似文献
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The present study aimed to provide preliminary data on the prevalence of oral stereotypic, locomotory stereotypic, and redirected behaviors as well as their associations with stable management and feeding practices. In this cross-sectional study, a total of 207 working horses used for leisure riding, equestrian sport, polo, endurance, and patrolling were selected from seven equine facilities. Data on the stable management and feeding practices were obtained through the stable records, interviews, and on-site monitoring visits, whereas the prevalence of abnormal behaviors in the studied population was determined using the instantaneous scan sampling method. Most horses in the present study worked for more than 8 hours per week (n = 93). In addition, more horses were fed three times per day (n = 65) with different amounts of hay, concentrate, and chaff. Among the study population, oral stereotypic behaviors had the highest prevalence (n = 281; 54%), followed by redirected behavior (n = 181; 34%), and locomotory stereotypic behaviors had the lowest prevalence (n = 63; 12%). The oral stereotypic behavior was found to be significantly influenced (P < .05) by the working hours, amount of hay, and amount of concentrate. Both locomotory stereotypic and redirected behaviors were found to be influenced (P < .05) by the number of feedings per day and the amount of hay. In summary, the present study has proven that the stable management and feeding practices could influence the prevalence of different abnormal behaviors in the majority of working horses, with oral stereotypy being the most common abnormal behavior in this country. 相似文献
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2009年9月26日—10月6日对人工养殖环境棘腹蛙(Paa boulengeri)非繁殖期摄食行为进行了观察。结果显示:非繁殖期,棘腹蛙幼蛙早于成蛙出来觅食,雄蛙早于雌蛙出来觅食;棘腹蛙摄食高峰期出现在19:00—20:00。在整个摄食过程中,棘腹蛙的行为可划分为静止、跳跃、转向、捕食、侵占、驱赶、打斗、爬行。棘腹蛙幼蛙与成蛙、雌性成蛙与雄性成蛙之间在摄食行为上存在差异,其中幼蛙与成蛙之间在跳跃、转动、捕食、侵占、驱赶、打斗行为上存在显著差异(P<0.05);成年雌蛙与雄蛙之间在侵占、驱赶、打斗行为上存在显著的差异(P<0.05)。 相似文献
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研究以国家自然科学基金项目支持的入境旅游市场调查数据为基础,以入境游客旅游决策行为为切入点,通过对西安入境欧洲游客的问卷调查,对其旅游决策行为及其影响因素进行分析研究,对西安欧洲旅游客源市场的拓展提出针对性的建议和对策。 相似文献