环境因子对卵形鲳鲹幼鱼耗氧率和排氨率的影响

运用封闭流水式实验方法研究温度、盐度、pH和流速对卵形鲳鲹(Trachinotus ovatus)幼鱼耗氧率和排氨率的影响.实验结果表明,随着温度的升高,耗氧率和排氨率均是先增大后减小,当温度为27℃时,耗氧率和排氨率达最大值,温度对卵形鲳鲹幼鱼耗氧率和排氨率的影响显著(P＜0.0l);耗氧率和排氨率随着盐度的升高均出...     

缺氧胁迫对菲律宾蛤仔(Ruditapes philippinarum)生理代谢的影响

采用苏木精-伊红(H-E)染色的方法,对菲律宾蛤仔(Ruditapes philippinarum)在缺氧(DO2 mg·L-1)胁迫20 d后组织结构进行研究,同时对菲律宾蛤仔在正常充氧(对照组)和缺氧状态下(缺氧组)的耗氧率、排氨率(NH3-N)、CO2排出率和O∶N进行研究,以期了解缺氧条件下菲律宾蛤仔生理代谢特征及其代谢变化规律。结果表明:缺氧胁迫20 d后菲律宾蛤仔组织结构与对照组相比出现差异,缺氧组个体组织中分布有零星的深紫色圆斑点,可能是由于缺氧引起菲律宾蛤仔脂质代谢发生异常,形成脂质沉积;在22℃水温条件下,随着缺氧胁迫时间的推移,缺氧胁迫对菲律宾蛤仔耗氧率、排氨率、CO2排出率影响显著;在缺氧胁迫2 d时,菲律宾蛤仔的耗氧率、排氨率和CO2排出率呈下降趋势,分别为0.566、0.079和26.236 mg·g-1·h-1,菲律宾蛤仔耗氧率和排氨率在缺氧胁迫2 d达到最低值,而CO2排出率在第20 d达到最低值,为7.422 mg·g-1·h-1,约为对照组的1/2;缺氧组的O∶N比值范围是6.25~12.11,且在缺氧20 d达到最高值,为12.11。由此可知,缺氧胁迫对菲律宾蛤仔的组织结构和生理代谢产生了影响,缺氧组的菲律宾蛤仔组织结构异常、活力下降,生理代谢功能降低,研究结果可为菲律宾蛤仔养殖的科学管理提供依据。     

盐度和温度对不同规格虎斑乌贼幼体的耗氧率、排氨率和窒息点的影响

为探究体重、盐度和温度对不同规格的虎斑乌贼(Sepia pharaonis)幼体耗氧率、排氨率以及其窒息点的影响。采用单因子试验设计和密闭静水法, 对不同体重下(0.212、0.385、0.476、0.597、0.754和0.946 g)虎斑乌贼幼体的耗氧率和排氨率, 以及不同体重(0.476、0.673、1.341、3.873和4.205 g)幼体的窒息点进行了测定, 同时研究了不同盐度(19‰、22‰、25‰、28‰和31‰)和温度(18、21、24、27和30℃)对不同规格[A: 体重(0.366±0.042) g, B: 体重(0.556±0.038) g, C: 体重(0.844±0.051) g]的虎斑乌贼幼体耗氧率(R_O)和排氨率(R_N)的影响。结果表明: (1)虎斑乌贼幼体体重对耗氧率和排氨率均影响显著(P<0.05)。随着幼体体重的增长, 耗氧率和排氨率显著下降, 个体越小耗氧率和排氨率越大; (2)盐度对幼体的耗氧率和排氨率有显著影响(P<0.05), 均随着盐度的增加呈先下降后上升的趋势, 其中, A规格和B规格的幼体在盐度25‰时, 耗氧率和排氨率显著低于盐度19‰、22‰和31‰时的3个试验组(P<0.05), 而与盐度28‰时无显著差异(P>0.05); C规格幼体的耗氧率在盐度28‰时显著低于盐度19‰组(P<0.05), 而排氨率在盐度25‰时显著低于盐度19‰和31‰两组(P<0.05)。盐度对A规格幼体的氧氮比(O/N)值有显著影响(P<0.05), 而对B规格和C规格的幼体无显著影响(P>0.05)。(3)温度对不同规格幼体的耗氧率和排氨率有显著影响(P<0.05), 均随温度的增长, 呈先上升后下降的趋势。其中, A规格和C规格幼体的耗氧率在27℃时, 显著高于18和30℃两组(P<0.05), B规格的在水温24℃时显著高于18和30℃(P<0.05); A规格和B规格幼体的排氨率分别在24和27℃时, 显著高于其他温度组(P<0.05), C规格的在温度27℃时, 显著高于18和30℃两组(P<0.05); 温度对A规格幼体的O/N值有显著影响(P<0.05), 而对B规格和C规格的幼体无显著影响(P>0.05)。(4)虎斑乌贼幼体的窒息点为0.84—1.62 mg/L, 随着体重的增加而逐渐降低。     

温度和个体大小对单齿螺耗氧率和排氨率的影响

采用静水法测定了不同温度、不同个体大小的单齿螺耗氧率和排氨率。结果表明:在16-33℃的实验温度范围内单齿螺的耗氧率(R_O)和排氨率(R_N)与软体部干重(W)都呈负相关,它们之间关系可以分别用幂函数R_O=aW^-b和R_N=a₁W^-b1表示。16～29℃温度范围内单齿螺的耗氧率和排氨率均随温度的升高而增加,29℃时耗氧率和排氨率达到最大值,当温度继续升高超过29℃后,耗氧率和排氨率则随温度的升高而下降,耗氧率、排氨率与温度之间呈显著的指数函数关系R_O=ce^dT和R_N=c₁e^d1T;不同个体大小单齿螺的O:N比在16～20℃时较大,Q₁₀取值范围0.56-3.74,平均值为1.64。方差分析表明,温度、软体部干重对单齿螺的耗氧率和排氨率均有极显著的影响(P<0.01)。     

温度对黑鱾幼鱼耗氧率和排氨率的影响

本文研究了温度对饱食和饥饿状态下黑纪(Girella melanichthys)幼鱼耗氧率和排氨率的影响.结果表明:在温度为15～30℃范围内,黑纪幼鱼在饱食状态下的耗氧率、饥饿状态下的耗氧率、饱食状态下的排氨率和摄食率均随温度的升高而增加(P＜0.01),30℃时达到最大,温度为32℃时,均下降;在温度为15～32℃范围内,黑鱾幼鱼在饥饿状态下的排氨率随温度升高而增加(P＜0.01),32℃时达到最大.多项指标表明黑纪幼鱼生长适温在30℃左右.     

鲻幼鱼耗氧率、排氨率和窒息点的研究

为探讨鲻幼鱼的耗氧率、排氨率和窒息点,采用封闭流水式实验方法,在不同体质量、光照、放养密度、水流速度以及昼夜更替的条件下,测定鲻幼鱼的耗氧率和排氨率,并且观测体质量对幼鱼窒息点和窒息时间的影响。实验期间水温为19℃±1℃,盐度30,pH7.7。研究结果显示:鲻幼鱼的耗氧率随体质量增加而上升,其变化趋势可用幂函数方程表达:Y=0.4759X0.1878(R2=0.9454);光照对耗氧率的影响较大,对排氨率无明显影响;放养密度对耗氧率的影响差异显著(P0.05),对排氨率的影响差异极显著(P0.01);幼鱼的呼吸代谢旺盛时段在中午11∶00至夜间23∶00;流速对耗氧率和排氨率的影响差异均极显著(P0.01);不同体质量幼鱼窒息点和窒息时间的差异极显著(P0.01)。     

栉孔扇贝耗氧率和排氨率的研究

1999年 4～ 6月 ,采用室内实验生态学方法对栉孔扇贝的耗氧率和排氨率进行了研究 .结果表明 ,在适宜的温度范围内 ,栉孔扇贝的耗氧率和排氨率均与温度成正比 ,而与体重呈负相关关系 .在实验室温度 (8～ 2 8℃ )条件下 ,栉孔扇贝的耗氧率为 0 .48～ 9.0 9mg·g-1·h-1,排氨率为 0 .0 5～ 1 0 1mg·g-1·h-1.其中耗氧率在 2 3℃时达到最高值 ,2 8℃时开始下降 ,而排氨率则呈持续升高趋势 .栉孔扇贝的日常代谢明显高于标准代谢 ,耗氧率和排氨率平均值分别提高约 35 .8%和 75 .9% .     

体质量和水温对太湖秀丽白虾人工驯养子代耗氧率和排氨率的影响

以太湖秀丽白虾(Exopalaemon modestus)人工驯养子代为实验样本,实验共设置6个体质量梯度及7个温度梯度,样本体质量范围为(0.12±0.01)～(1.93±0.05)g,实验温度范围为12℃～30℃,研究了体质量及水温对耗氧率和排氨率的影响。结果表明:秀丽白虾耗氧率变幅为0.1497～0.9053mg·g-1·h-1,均值为0.3901mg·g-1·h-1;排氨率变幅为0.0165～0.0866mg·g-1·h-1,均值为0.0379mg·g-1·h-1。体质量、水温及两者的交互效应均对耗氧率和排氨率具有极显著的影响(P0.01)。体质量与耗氧率和排氨率之间的回归关系分别符合幂函数方程Ro=0.3114W-0.2414(r=-0.436)和Rn=0.0307W-0.3007(r=-0.653);水温与耗氧率和排氨率之间的回归关系分别符合指数方程Ro=0.0711e0.0749t(r=0.877)和Rn=0.0113e0.0530t(r=0.747);体质量、水温与耗氧率及排氨率的二元回归方程分别为Ro=0.028T-0.147W-0.053(r=0.948)和Rn=0.002T-0.017W+0.013(r=0.922)。耗氧率和排氨率Q10变幅分别为1.17～4.20和1.15～2.29,均值分别为2.10和1.64。在实验温度范围内,氧氮比均随着水温的上升而增大,变幅为7.42～13.62,均值为10.04。秀丽白虾在低温阶段(12℃～18℃)主要以蛋白质为供能物质,在高温阶段(21℃～30℃)对脂肪的利用有所增加,中等规格个体的脂肪代谢率最高。     

西施舌的耗氧率与排氨率研究

采用室内实验生态学方法研究了不同栖息水温和不同溶解氧水平下处于标准代谢状态的西施舌耗氧率与排氨率,并测定了窒息点.结果表明,在25 ℃时,水中DO≥3.11±0.15 mg·L^-1时,西施舌的耗氧率和排氨率分别为0.7±0.05 mg·g^-1·h^-1和2.56±0.05 μmol·g^-1·h^-1,处于相对稳定状态;当DO低于此值则代谢出现异常,耗氧率随DO下降而下降,直到窒息为止,其窒息点为1.22±0.06 mg·L^-1,而排氨率也呈直线下降,但排氨停止滞后于耗氧停止.耗氧率与栖息水温呈二次线型关系:OCR=-0.0027T²+0.1367T-0.9557,R²=0.972;水温为25.3 ℃时,西施舌的耗氧率达到最大,为0.77 mg·g^-1·h^-1.处于适温状态(15 ℃和20 ℃)的O/N值要高于低温(10 ℃)和高温(25 ℃和30 ℃)时的O/N值,西施舌在适宜条件下更多地依赖于脂肪供能维持标准代谢,而在环境不适时则更多地调用机体的蛋白质来维持生理代谢需要.     

环境因子及规格对菲律宾蛤仔幼贝潜沙行为的影响

作为埋栖型滩涂贝类的典型代表种类,菲律宾蛤仔Ruditapes philippinarum具有很强的潜沙行为。为了进一步了解其生态行为学,在室内实验室条件下,模拟了常见环境因子温度、盐度、p H值以及流速和规格大小对蛤仔幼贝(6—12 mm)潜沙速度的影响。结果表明,温度10—30℃,盐度25—30,p H值在6.0—9.0范围内蛤仔幼贝均能100%潜沙;在试验观察的4—5 h内,盐度由30突变至10时没有蛤仔潜沙,突变至20时有20%—30%潜沙(20℃,庄河蛤仔)或100%潜沙(15℃,福建蛤仔);p H值由8.0突变至10.0时不能潜沙;以暂养海水的温度(15或20℃)、盐度(30)和p H值(8.0)为中心,随着各个指标向两侧突变潜沙时间延长;流速为3、4和5 cm/s时,随流速增大潜沙速度加快;在规格6、9 mm和12 mm的幼贝中,以12 mm潜沙速度最快。若以半数潜沙时间(ET_(50))为判定指标,则适宜潜沙温度为15—20℃,盐度为25—30,p H值为7—9(莆田蛤仔)和8.0(庄河蛤仔)。在适宜条件下,蛤仔幼贝1 min内开始潜沙,3 min内有半数潜沙,5 min便全部潜沙。研究发现环境突变对蛤仔潜沙有明显影响,在天然海区放养蛤仔时应该注意购买地和放养海区温度、盐度和p H值的差异,并且选取10 mm以上幼贝放养效果较好。所得结论对完善菲律宾蛤仔幼贝的行为学及其底播养殖技术提供了有意义的参考。     

Comparison of the metabolism of Acartia clausi and A. tonsa: influence of temperature and salinity

In the Marseilles region (French Mediterranean coast), A. clausi is one of the most abundant copepod species of the Gulf of Fos while A. tonsa constitutes the almost exclusive copepod species of the Berre lagoon, a neighbouring semi-closed brackish area communicating with the gulf. As different ecophysiological capabilities to stand the various temperature, salinity and food conditions could explain why these two species do not coexist in the same environment, comparative experiments were performed on metabolism and feeding. The respiration and ammonia excretion of the two species were measured in different combinations of temperature (10, 15 and 20 degrees C) and salinity (15, 25 and 35 per thousand). For each temperature, at the salinity of 35 per thousand, respiration rates were less in A. clausi than in A. tonsa, the contrary being observed at the lowest salinity. At any temperature ammonia excretion was greater at the intermediate salinity in A. tonsa and least in A. clausi. In Acartia tonsa, Q(10) of respiration and excretion were minimum at the lowest salinity, while in A. clausi they were unaffected by salinity variation. The O:N atomic ratio (from respiration and ammonia excretion rates) was significantly more elevated in A. clausi (mean 21.2; range 13.6-28.7) than in A. tonsa (mean 11.3; range 4.2-25) suggesting a more proteinic oriented metabolism in the later. Feeding experiments where Dunaliella tertiolecta30 per thousand) or lagoon (<16 per thousand) salinity. The relationships between ingestion and food concentration in the two species were not significantly different. These different results are compared to other ecophysiological information concerning these Acartia species (survival tolerances, osmotic regulation, feeding behaviour) and are discussed in relation with the characteristics of their niches in the studied region.     

Effects of low salinity on juvenile pink shrimp Farfantepenaeus paulensis (Perez-Farfante 1967, Crustacea)

It is of paramount importance to study salinity tolerance of commercially important crustaceans, such as the pink shrimp Farfantepenaeus paulensis to determine possible mortality causes in the wild and in aquaculture in oligohaline waters. The aim of this study was to determine the lethal salinity concentration (LC50) for juvenile pink shrimp F. paulensis and measure its oxygen consumption and ammonia excretion at different salinity levels. Shrimp of two length classes (49.4?±?4.3 and 78.5?±?5.5?mm) were placed in 10-L containers and exposed to salinity levels of 35, 30, 25, 20, 15, 10 and 5. The experiments were tripled, with seven shrimp in each container. The average lethal concentration (LC50s) for an exposure of 24?h was 13.33 (11.26–15.78) and 10.26 (8.60–12.64), respectively, for the two classes of juveniles. For an exposure of 48?h, LC50s were 12.71 (10.68–15.12) for the larger animals and 9.20 (7.34–11.52) for the smaller ones. There was an inverse relationship between salinity and rates of oxygen consumption and ammonia excretion. The average reduction in specific oxygen consumption in salinities 20, 25 and 30 showed a decrease in metabolic rate of 63, 80 and 82%, respectively, in relation to salinity level 0. The same occurred for the averages of ammonia excretion at salinity levels of 15, 20, 25, 30 and 35, which represented low metabolic rates of 57, 61, 70, 71 and 74% respectably in relation to salinity level 0.     

Oxygen consumption, ammonia excretion and protein use in response to thermal changes in juvenile Atlantic salmon Salmo salar

Experiments were designed to examine the effects of various temperature challenges on oxygen consumption and ammonia excretion rates and protein utilization in juvenile Atlantic salmon Salmo salar . Fish acclimated to 15° C were acutely and abruptly exposed to either 20 or 25° C for a period of 3 h. To simulate a more environmentally relevant temperature challenge, a third group of fish was exposed to a gradual increase in temperature from 15 to 20° C over a period of 3 h ( c. 1·7° C h⁻¹). Oxygen consumption and ammonia excretion rates were monitored before, during and after the temperature shift. From the ammonia excretion and oxygen consumption rates, protein utilization rates were calculated. Acute temperature changes (15–20° C or 15–25° C) caused large and immediate increases in the oxygen consumption rates. When the temperature was gradually changed ( i.e. 1·7° C h⁻¹), however, the rates of oxygen consumption and ammonia excretion were only marginally altered. When fish were exposed to warmer temperatures ( i.e. 15–20° C or 15–25° C) protein use generally remained at pre-exposure (15° C) levels. A rapid transfer back to 15° C (20–15° C or 25–15° C) generally increased protein use in S. salar . These results indicate that both the magnitude and the rate of temperature change are important in describing the physiological response in juvenile salmonids.     

Physiological energetics of the zebra musselDreissena polymorpha in lakes III. Metabolism and net growth efficiency

Oxygen consumption and ammonia excretion of the zebra musselDreissena polymorpha from 3 sites in lakes were estimated regularly over the course of 1 1/2 years at ambient temperature. They showed a pronounced annual cycle, when expressed in absolute terms (at standard shell length) and in weight specific terms (at standard tissue weight). The atomic ratio of oxygen consumed to ammonia-N released (O/N ratio) was lowest in late summer at all sites (10 to 20) and highest during winter and spring (50 to > 100). The mean body weight exponent pooled from these sites was 0.78 (95% confidence interval±0.07) for the oxygen consumption rate and 0.80 (confidence interval±0.10) for the ammonia excretion rate. Both oxygen consumption and ammonia excretion were significantly correlated with the water temperature at the 2 shallow water sites, where temperature variation was most pronounced. Correlation with seston content or gonad volume were insignificant at these sites. The quotient of filtration capacity to oxygen consumption rate was about 3 times higher at the site with the poorest food conditions compared to the other sites. Net growth efficiency was highly variable; its annual average was 35 to 40 per cent and independent of locality and animal size.     

温度对橄榄蛏蚌耗氧和氨氮排泄的影响

The respiration metabolismand excretion of marinebivalves were studied by different researchers[1—6].Themetabolic rate of bivalves is influenced by a number ofvariables,includingtemperature,body size,oxygen ten-sion,food concentration,reproductive state,activityleveland physiological condition.The excreted metabolites ofbivalves include ammonia,urea,uric acid and others,with ammonia comprising70%of the total excretion.Solenaia oleivorais a proper freshwater bivalve in China.For the consumer it has the follo...     

温、光、盐对硅藻STR01生长、总脂、脂肪酸的影响

为了优化新分离STR01的生态培养条件, 采用单因子试验和正交试验研究了不同温度、光照强度、盐度和温、光、盐三因素三水平对该藻的生长、总脂和脂肪酸组成影响。结果表明: 温、光、盐对STR01的生长、总脂和脂肪酸组成影响显著(P<0.05)。生长的适宜温度为15—35℃, 最适25—30℃(K值达0.679—0.682), 总脂含量积累的最适温度是25℃(总脂可达17.23%), 温度20℃时有利于该藻PUFA的积累, 可达34.23%。STR01生长的适宜光照强度为40—120 μmol/(m2·s), 最适光强为60 μmol/(m2·s), 光照强度40 μmol/(m2·s)有利于该藻的PUFA积累, 可达34.29%。STR01生长的适宜盐度为10—35, 最适盐度25, 盐度25时PUFA含量较高(43.42%)。正交试验结果表明温度对STR01的平均相对生长速率和总脂含量影响显著, 生长的最优组合: 温度30℃、光照强度60 μmol/(m2·s)、盐度25, 该组合下的生长速率达0.756; 总脂含量积累的最优组合: 温度30℃、光照强度60 μmol/(m2·s)、盐度20, 该组合下的总脂含量为20.00%。PUFA的最优组合: 温度25℃、光照强度60 μmol/(m2·s)、盐度20, 该组合下PUFA的含量为35.37%。综上所述: 该藻生长迅速, 总脂含量较高, PUFA丰富, 是一种可开发利用的耐高温浮游硅藻。     

Metabolic demand and growth of juveniles of Centropomus parallelus as function of salinity

The effect of salinity and time of exposure on metabolism and growth of juveniles of fat snook, Centropomus parallelus, were investigated. Food conversion efficiency (FCE), specific growth rate (SGR), oxygen consumption, ammonia excretion rate and O:N (oxygen/nitrogen) ratio were assessed on groups of fat-snook (mean weight 2 g) acclimated for 15- and 30-day periods, to 5‰, 20‰ and 30‰ salinities. For 15-day period, differences between FCEs as well as SGRs at different salinities were not significant. For 30-day period, however, these differences were significant between 5‰ and the other salinities, with the highest and lowest values at 5‰ and 30‰, respectively, for both parameters. Salinity and acclimation period exerted significant influence on the oxygen consumption, ammonia excretion and the O:N ratio of juveniles of C. parallelus. The lowest and highest oxygen consumption was at 20‰ for 15- and 30-day period, respectively. Differences in oxygen consumption between fishes maintained at 5‰ and at 30‰ were not significant, at each period, while between those maintained at 5‰ and 20‰, and at 20‰ and 30‰ differences were significant. Ammonia excretion rates were significantly different between all salinities, at each period, and between periods at each salinity, except at 30‰. The highest and lowest rates were found at 5‰ and 30‰, respectively. The highest O:N ratio for 15-day period was at 30‰ with no difference between those at 5‰ and 20‰. For 30-day period, differences of O:N ratio were significant between salinities. The effect of acclimation period on the O:N was significant only at 20‰. Although C. parallelus is a fish species adapted to face a wide variation of environmental salinity, results show that juvenile fishes kept at different salinities, in laboratory, found better condition to efficiently channel the energy of food into growth at 5‰ for both acclimation periods.