【作者】 陈波见；

【导师】 王宇翔； 付世建；

【作者基本信息】 重庆师范大学 ， 水生生物学， 2011， 硕士

【摘要】 为了考察温度对中华倒刺鲃Spinibarbus sinensis,鳊鱼Parabramis pekinensis,草鱼Ctenopharyngodon idellus,花鲢Aristichthys nobilis,白鲢Hypophthalmichthys molitrix以及建鲤Cyprinus carpiovar Jian的幼鱼常规代谢率（RMR）、临界氧压(P_crit)以及鳃部形态结构的影响,首先将6种幼鱼分别驯化在10℃、15℃、20℃、25℃、30℃条件下2周。之后分别用密闭呼吸室测定代谢率并以双线法计算P_crit。在每个温度组分别选取每种实验鱼3条,取右侧第二鳃弓做扫描电镜检查。旨在揭示栖息于不同水层的温水性鲤科鱼类其耐低氧能力受环境温度的影响的机制,为三峡库区鱼类资源保护提供有价值的资料。研究结果:1.温度和鱼种对常规代谢率的影响温度和鱼种对6种鲤科鱼类幼鱼的常规代谢率有显著影响（交互作用P<0.05）。所有实验鱼的常规代谢率随温度上升（10℃、15℃、20℃、25℃、30℃）而上升,且上升速率和幅度因种而异。在大多数温度条件下,各实验鱼种之间常规代谢率差异显著（P<0.05）;仅在25℃时,除花鲢以外,各鱼种的常规代谢率处于同一水平。同一鱼种内,温度对常规代谢率的影响显著（P<0.05）,且影响因鱼种的不同而表现出不同规律。2.温度和不同鱼种类对P_crit的影响温度和不同鱼种类的实验鱼对P_crit影响显著存在交互作用（P<0.05）。在各个温度下,P_crit表现出高低两种水平;不同鱼种对P_crit的影响显著（P<0.05）:在绝大多数温度组（10℃、15℃、20℃、25℃）,花鲢、白鲢和建鲤的P_crit显著低于中华倒刺鲃,鳊鱼和草鱼;在30℃时,除了中华倒刺鲃以外,所有实验鱼的P_crit处于一个相近的水平。在同一鱼种内,温度对P_crit的影响表现出3种类型:随着温度的升高,1)中华倒刺鲃的P_crit从17.05±1.25 （torr）升高至24.82±1.80 （torr）,表现出明显上升的趋势（P<0.05）;2)鳊鱼和草鱼的P_crit分别从29.20±4.33 （torr）和21.70±2.51 （torr）下降至16.70±0.91 （torr）和15.37±1.09 （torr）,呈显著下降特征（P<0.05）;3)白鲢和建鲤的P_crit虽然在整个温度区间不受温度变化的影响（P>0.05）,但在不同温度区间内有着不同的变化趋势:20℃之前,其P_crit随温度升高而上升;20℃之后,其P_crit随温度升高而降低。花鲢的P_crit变化趋势与白鲢及鲤鱼类似,然而在整个温度区间其P_crit变化差异显著（P<0.05）。3.温度对鳃部形态结构的影响我们首次发现草鱼、白鲢和花鲢的鳃部在变化的温度中具有可塑性。在低温时（10℃）它们的鳃丝都埋藏在间质细胞中,而使整体鳃丝表现出“棒状”的外形;随着温度上升,间质细胞逐渐凋亡,使鳃丝暴露,渐渐转变为正常的鳃丝结构特征。而中华倒刺鲃,鳊鱼以及建鲤的鳃部则不具备类似的可塑性;随着环境温度的升高,它们的鳃丝没有出现明显的变化。以上结果表明:1.鲤科鱼类的常规代谢水平率随环境温度的升高而上升;但升高的幅度和速率与鱼种的生活习性有关。绝大多数实验鱼的常规代谢率在25℃时处于同一水平。这说明温水性鲤科鱼类的最适温度可能为25℃。2.实验中的6种鲤科鱼类P_crit对温度的反应各不相同,呈现出随温度升高而升高;降低及相对保守等3种类型;而且这些鱼类在自然界分布与P_crit无关;3.鳃部的可塑性与P_crit的变化无明显关联,摄氧与维持离子平衡的权衡可能是促使鱼类进行低温下鳃部结构改变的重要因素。更多还原

【Abstract】 To investigate the temperature effect on RMR, P_crit and gill morphology in junvenile Spinibarbus sinensis, Parabramis pekinensis, Ctenopharyngodon idellus, Aristichthys nobilis, Hypophthalmichthys molitrix and Cyprinus carpiovar Jian. We firstly randomly allocated fishes at 5 rearing temperatures （10℃、15℃、20℃、25℃、30℃） for 2 weeks. Then determined RMR by using sealed respirometry, calculated P_crit by“two-line”regression method. The second gill arch from the right hand side of 3 fish from species at each rearing temperature was carefully dissected out, rinsed and fixed for later scanning electron microscopy. We hope that our study could explore the hypoxia tolerance mechanism in warm water carp from different vertical habitants and provide practical information for protection of fish resources in the Three Gorges reservoir region.The results are:1. Effect of temperature and genus on RMRTemperature and genus together have significant effect on RMR in juvenile carps （ interaction effect P<0.05）. The RMR of all experimental species elevated along with rearing temperature （10℃、15℃、20℃、25℃、30℃）. The magnitude and rising pace was in accordance with species characteristics. At most rearing temperature, there were significant differences in RMR among species （P<0.05）; only at 25℃, all except Aristichthys nobilis reached to a similar zone in RMR level. Put the genus factor aside, temperature has profound effect on RMR within species （P<0.05）, the effect was represented in different patterns.2. Effect of temperature and genus on P_critTemperature and genus together have significant effect on P_crit in juvenile carps （interaction effect P<0.05）. At each rearing temperature, genus has significant effect on P_crit （P<0.05）, two levels were revealed: at most temperature groups （10℃, 15℃, 20℃,25℃）, the P_crit of Aristichthys nobilis, Hypophthalmichthys molitrix and Cyprinus carpiovar Jian were significant lower than that of Spinibarbus sinensis, Ctenopharyngodon idellus and Parabramis pekinensis. P_crit value of all species reach a similar level at 30℃, except Spinibarbus sinensis. Within species, the temperature effect on P_crit represented 3 types: Temperature had significant effect on P_crit in Spinibarbus sinensis, Parabramis pekinensis and Ctenopharyngodon idellus （P<0.05）. With ascending temperature, Spinibarbus sinensis had its P_crit increased from 17.05±1.25 （torr） to 24.82±1.80 （torr）; the P_crit values of Parabramis pekinensis and Ctenopharyngodon idellus decreased from 29.20±4.33, 21.70±2.51 to 16.70±0.91, 15.37±1.09, separately. Hypophthalmichthys molitrix and Cyprinus carpiovar Jian’P_crit values showed a firstly increased, then dropped pattern, with a peak P_crit values at 20℃. Though temperature had significant effect on P_crit in Aristichthys nobilis （P<0.05）, its P_crit changing type was similar to Hypophthalmichthys molitrix and Cyprinus carpiovar Jian’s, of which was not affected by temperature change.3. Effect of temperature on gill morphology in carps.We first found that the gill plasticity existed in Ctenopharyngodon idellus, Aristichthys nobilis, and Hypophthalmichthys molitrix due to temperature changes. At lower temperature, the lamellae were embedded with a large interlamellar cell mass （ILCM）, resulting in a sausage-like morphology. As temperature went higher, through a apoptosis and cell cycle arrest process, the gills transformed into‘normal’gills with protruding lamellae. However, Spinibarbus sinensis, Parabramis pekinensis and Cyprinus carpiovar Jian didn’t have such gill remodeling potential.In conclusion:1. The RMR in carps elevated along with rearing temperature grew; the magnitude and rising pace was in accordance with species characteristics. Most carp’s RMR reached a similar zone at 25℃, which suggested 25℃might be the optimal temperature for warm water carps.2. The P_crit responses towards temperature varied among species, which revealed 3 patterns: increasing, decreasing and being conservative along with temperature elevation. The wild distribution has no relation with P_crit.3. The gill plasticity has no relation with P_crit. The oxygen acquisition and ion endogenous balance trade off might be the driven force of gill remodeling.更多还原