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1.
Growth and energy budget of the polychaete, Neanthesjaponica, at various temperatures (17, 20, 23, 26 and 29℃) were investigated in this study. The growth, as indicated by final dry weight and specific growth rate (SGR), increased with increasing temperature, with the maximum level at 26℃, and then decreased significantly at 29℃. A similar trend was observed in feeding rate, food conversion efficiency (FCE) and apparent digestive rate (ADR). However, no significant differences were detected in ADR among all the temperature treatments. In the pattern of energy allocation, faeces energy was only a small component of energy budget and had little influence on the proportion of food energy allocated to growth. The metabolic energy accounted for a large portion of energy intake for each temperature treatment. The nitrogen excretion was appreciable with changing temperature. The two expenditure terms (respiration energy and excretion energy) in energy budget were the major factors influencing the proportion of food energy allocated to growth. These results revealed that temperature affected the growth of N. japonica mainly by influencing feeding rate and FCE. In addition, regression equations describing the relationship between feeding rate, faecal production, SGR, FCE and temperature were obtained. The optimum temperatures for feeding rate, FCE and SGR were estimated at 25.01 ℃, 24.24℃ and 24.73 ℃, respectively, from the regression equations. 相似文献
2.
Growth and energy budget of the polychaete, Neanthes japonica, at various temperatures (17, 20, 23, 26 and 29°) were investigated in this study. The growth, as indicated by final dry
weight and specific growth rate (SGR), increased with increasing temperature, with the maximum level at 26°C, and then decreased significantly at 29°C. A similar
trend was observed in feeding rate, food conversion efficiency (FCE) and apparent digestive rate (ADR). However, no significant differences were detected in ADR among all the temperature treatments. In the pattern of energy allocation, faeces energy was only a small component of energy
budget and had little influence on the proportion of food energy allocated to growth. The metabolic energy accounted for a
large portion of energy intake for each temperature treatment. The nitrogen excretion was appreciable with changing temperature.
The two expenditure terms (respiration energy and excretion energy) in energy budget were the major factors influencing the
proportion of food energy allocated to growth. These results revealed that temperature affected the growth of N. japonica mainly by influencing feeding rate and FCE. In addition, regression equations describing the relationship between feeding rate, faecal production, SGR, FCE and temperature were obtained. The optimum temperatures for feeding rate, FCE and SGR were estimated at 25.01°C, 24.24°C and 24.73°C, respectively, from the regression equations. 相似文献
3.
水温28±1℃条件下,投喂人工配合饲料,研究摄食水平1%、2%、3%、4%、5%(每日投喂量占初始实验鱼湿重的质量百分比)及饱食对卵形鲳鲹幼鱼(初始体重5.77±0.45g)生长及能量收支的影响。结果表明,卵形鲳鲹幼鱼特定生长率、转化效率、摄食率随着摄食水平的提高而增长,摄食水平达4%时干重特定生长率与饱食组差异无显著性(P>0.05),摄食水平达5%时,湿重、蛋白质和能量生长率与饱食组差异无显著性(P>0.05);摄食水平达4%时能值转化效率与饱食组差异无显著性(P>0.05),摄食水平达5%时,干重、蛋白质转化效率与饱食组差异无显著性(P>0.05);摄食水平达2%时干重、蛋白质表观效率与饱食组差异无显著性(P>0.05),摄食水平达4%时,能量表观效率与饱食组差异无显著性(P>0.05)。生长能分配率随摄食水平升高而显著增加(P<0.05),代谢能、排粪能及排泄能分配率的变化则相反。建立了6种摄食水平条件下卵形鲳鲹幼鱼的能量收支方程。 相似文献
4.
Metabolism of polychaete Neanthes japonica Izuka: relations to temperature, salinity and body weight
Polychaete Neanthesjaponica is a species geographically specific in China and Japan with important scientific implication and commercial value. In this study, the relations of body weight, salinity and temperature to oxygen consumption and ammonia excretion of N. japonica were determined. Threedifferent groups in body weight (large: 2.34±0.36 g, middle: 1.50±0.21 g and small: 0.62±0.12 g) were set for all experiments. Results show that the body weight is negatively related to the rates of oxygen consumption and ammonia excretion; and the relationship is significant. The oxygen consumption and ammonia excretion at 24℃ decreased at salinity from 5 to 30 and increased above 30, indicating that both lower and higher salinity are adverse and certain degree of salinity stress is necessary for enhancing the energy demand. At salinity 30, rising temperature from 18℃ to 30℃, the oxygen consumption increased before 27℃ and then decreased. However, the relation of ammonia excretion and temperature seems more complex. Two-way ANOVA shows that salinity, temperature and body weight all have a significant effect on the oxygen consumption and ammonia excretion of the worm. Moreover, interaction between salinity/temperature and body weight is also significant. O:N (oxygen/nitrogen) ratio varies greatly in this case from 5.97 to 463.22, indicating that N. japonica can regulate the type of metabolic substrate against environment changes. 相似文献
5.
在水温(28±1)℃,以配合饲料及最大摄食量的条件下,研究卵形鲳鲹(Trachinotus ovatus)幼鱼[初始体重(5.77±0.45)g]在盐度10、15、20、25、30和35下的生长及能量收支。结果表明:在盐度25时,湿重、干重、蛋白质及能量指标的特定生长率均达到最大值,分别为3.21%、2.06%、4.76%和4.66%;干重、蛋白质和能量指标的摄食率也达最大,分别为20.31%、13.57%和12.21%;干重、蛋白质和能量指标的转化效率也达最大,分别为35.61%、46.60%和52.78%。可见,盐度对卵形鲳鲹幼鱼的特定生长率、摄食率、转化效率及能量收支有显著影响。盐度对吸收效率则无显著影响,蛋白质和能量的平均吸收效率分别为94.91%和92.45%;在盐度25,卵形鲳鲹幼鱼得到最佳的能量分配模式,其收支方程为:100.00C=7.30F+10.13U+29.80R+52.77G。 相似文献
6.
Metabolism of polychaete Neanthes japonica Izuka: relations to temperature, salinity and body weight
Polychaete Neanthes japonica is a species geographically specific in China and Japan with important scientific implication and commercial value. In this
study, the relations of body weight, salinity and temperature to oxygen consumption and ammonia excretion of N. japonica were determined. Three different groups in body weight (large: 2.34±0.36 g, middle: 1.50±0.21 g and small: 0.62±0.12 g) were
set for all experiments. Results show that the body weight is negatively related to the rates of oxygen consumption and ammonia
excretion; and the relationship is significant. The oxygen consumption and ammonia excretion at 24°C decreased at salinity
from 5 to 30 and increased above 30, indicating that both lower and higher salinity are adverse and certain degree of salinity
stress is necessary for enhancing the energy demand. At salinity 30, rising temperature from 18°C to 30°C, the oxygen consumption
increased before 27°C and then decreased. However, the relation of ammonia excretion and temperature seems more complex. Two-way
ANOVA shows that salinity, temperature and body weight all have a significant effect on the oxygen consumption and ammonia
excretion of the worm. Moreover, interaction between salinity/temperature and body weight is also significant. O:N (oxygen/nitrogen)
ratio varies greatly in this case from 5.97 to 463.22, indicating that N. japonica can regulate the type of metabolic substrate against environment changes.
Supported by the National Natural Science Foundation of China (No. 30490233) and the Three-Gorge Project and the Estuarine
Environment (No. SX2004-018) from the Three Gorges Project Construction Committee 相似文献
7.
XIONG Yinghuai WANG Xin DONG Shuanglin WANG Fang YANG Jingwen ZHOU Yangen 《中国海洋大学学报(英文版)》2019,(2):509-518
This study examined the effect of different salinities(0, 5, 10, 15, 20, 25 and 30) on the growth performance and energy budget of juveniles of two different ecotypes of Oncorhynchus mykiss, landlocked rainbow trout and anadromous steelhead trout. In the 42 d experiment, fish were cultured in three replicate tanks per salinity treatment(eight fish per tank). At the end of the experiment, the growth of rainbow and steelhead trouts was significantly higher at salinities of 5 and 10, respectively, than at all other salinities. The protein, lipid and energy content of both ecotypes declined with the increase of salinity. Based on their energy budgets, the percentage of energy consumed for growth by rainbow and steelhead trouts were significantly higher at salinities of 5(34.00% ±1.69%) and 10(43.76% ± 1.29%), respectively, than at all other salinities. The percentage of energy consumed for respiration by rainbow and steelhead trouts was lower at salinities of 5(54.90% ± 1.77%) and 10(46.73% ± 0.62%), respectively, than at all other salinities. Our results indicated that the salinity adaptation ability of juvenile steelhead trout was slightly better than that of juvenile rainbow trout, and salinities of 10 and 5, respectively, were most suitable for growth of these two fishes. 相似文献
8.
半干旱夏季放牧草地能量收支和地表蒸散量变化特征 总被引:1,自引:0,他引:1
以半干旱区域典型夏季放牧草地为研究对象,采用涡动相关法,获取了2012年5月至2013年5月水汽和能量通量观测数据,分析夏季近地层能量收支特征、地表蒸散量变化及其气象控制因子。观测结果显示:生长季有效能量的分配以潜热通量为主,非生长季则以感热通量为主;地表蒸散日总量最大值为3.0mm,日蒸散量大小主要取决于土壤温度、气温和净辐射;降雨量的季节分布是地表蒸散量季节变化的一个重要的影响因子。 相似文献
9.
The effects of body weight and temperature on the carbon budget of the juvenile bastard halibut, Paralichthys olivaceus , were studied at temperature 13.5, 18, 21.5 and 24 ℃, respectively. The carbon intake, faecal and growth carbon were measured, and the carbon respiration was calculated using the carbon budget equation(CC=GC+FC+RC). The combined relationship between different components of the carbon budget, body weight and temperature could be described by regression equations: CC =1.0206 W 0.8126 e 0.1483 T; G=0.0042 W 1.4096 (-5.11 T 3+285.90 T2-5173.72 T +30314.03); FC =0.0485 W0.7711e 0.1624 T ; UC = 1.4333 W 0.6715e 0.1487 T. Body weight had no significant ffect on the carbon absorption efficiency and the conversion efficiency. 相似文献
10.
1 INTRODUCTION White shrimp Litopenaeus vannamei, a tropical species, naturally distributes along the eastern Pa- cific coast from northern Mexico to northern Peru along 20℃ isotherms, was introduced into China in 1988 (Cai and Chen, 1995). Temperature w… 相似文献
11.
温度对奥尼罗非鱼仔稚鱼生长、饲料利用和消化酶活力的影响 总被引:1,自引:0,他引:1
研究了温度22、25、28、31和34℃下奥尼罗非鱼(Oreochromis niloticus×O.aureus)仔稚鱼生长、饲料利用和消化酶活力。结果表明:1)不同温度对奥尼罗非鱼仔稚鱼生长有显著影响(P<0.05),温度为31℃时,仔稚鱼生长速度和绝对增重率最高,分别为0.08cm/d和0.035g/d;温度为22℃时最低,仅0.06cm/d和0.020g/d。2)饲料系数在28℃时最低,仅1.90;22和34℃时较高,达2.14和2.17,各组差异显著(P<0.05)。3)在仔稚鱼发育和存活率上,当温度在22~34℃时,温度越高,仔稚鱼发育越好;各组仔稚鱼的存活率介于93.7%~94.7%,差异不显著(P>0.05)。4)在消化酶活力上,胃蛋白酶、胰蛋白酶和淀粉酶活力随温度升高而升高,均在34℃时活力最高;脂肪酶活力在31℃时达到最高,22℃时活力最低。 相似文献
12.
用单因子和正交实验方法研究了温度和光照对小环藻生长和叶绿素a含量的影响。结果表明,温度对小环藻生长和叶绿素a含量有极显著影响(P<0.01),当温度在30~40℃时比增长率和叶绿素a含量分别为0.37~0.38 d-1和1 084.4~1 214.2μg.L-1,均显著高于其他温度组。光照对小环藻生长和叶绿素a含量有极显著影响(P<0.01),当光照强度从29.25~146.26μmol.m-2.s-1时比增长率最高,为0.30~0.32 d-1;而叶绿素a含量则在9.75~58.50μmol.m-2.s-1时最高,达709.7~731.8μg.L-1,极显著高于其他照度组。正交实验结果表明:在35℃、87.75μmol.m-2.s-1条件下种群增长最快,比增长率为0.4402 d-1;在30℃、29.25μmol.m-2.s-1时,叶绿素a含量最高,为1 746.6μg.L-1。 相似文献
13.
14.
ZHOU Yangen BAO Weiyang SU Yuepeng HUANG Ming WANG Xingqiang YAN Binlun MA Shen 《中国海洋大学学报(英文版)》2022,21(1):171-178
This study was to evaluate the effect of stocking densities on the nitrogen and phosphorus budgets for a polyculture of the crab Portunus trituberculatus and the Pacific white shrimp Litopenaeus vannamei.The shrimps(initial weight,0.012 g)were cultured at a density of 45 shrimp m-2,and juvenile crabs(initial weight,0.024 g)were cultured at five densities of 0,3,6,9,and 12 crabs m-2.The treatments were grouped as C0S45,C3S45,C6S45,C9S45,and C12S45,respectively.Water quality parameters,growth of shrimp and crabs,and nitrogen and phosphorus budget were measured.The results indicated that the shrimp performances in polyculture treatments C3S45 and C6S45 were superior to those in the crab-free treatment(C0S45).The crab in treatments C3S45 and C6S45 exhibited a significantly higher final mean weight and carapace width/length than those in treatments C9S45 and C12S45.The final size and survival of crabs had a negative correlation with the increasing crab stocking density.The contents of total phos-phorus and total nitrogen and the comprehensive contamination index values were higher in the C9S45 and C12S45 treatments than in the other treatments.The conversion ratios of nitrogen for crab and shrimp growth in treatment C3S45 were significantly higher than those in the crab-free treatment.These findings indicate that polyculturing shrimp with crabs at suitable densities can improve productivity,profitability,nutrient utilization,and the environmental quality.From the 60-day treatments,the optimal culture densi-ties were 3-6 crabs m-2 and 45 shrimps m-2. 相似文献
15.
吉富罗非鱼最适生长水温研究 总被引:3,自引:0,他引:3
为研究不同养殖水温对吉富罗非鱼摄食和生长的影响,了解吉富罗非鱼的最适生长水温,实验设计28℃、30℃、32℃、34℃4个不同温度梯度,周期45 d。结果表明:不同水温环境下吉富罗非鱼表现出不同的生长特性,养殖在30℃水体中的罗非鱼生长速度明显高于其他温度组;水温对吉富罗非鱼的特定生长率、绝对增重率、饲料转化率、摄食率有显著影响(P<0.05),之间的相关关系可以用二次回归曲线来描述,特定生长率(SGR)与水温的关系式为rSGR=-19.255+1.3794T-0.0235T2,摄食率(FR)与水温的关系式为rFR=-22.175+1.5901T-0.026 6 T2,饲料转化率(FCR)与水温的关系式为rFCR=34.041-2.2256T+0.0382 T2;吉富罗非鱼的最适生长水温为29.3℃,最大摄食率的水温为29.9℃,最高食物转化率水温为29.1℃。 相似文献
16.
城镇用地增长边界能够有效控制城市的无序蔓延,对城市健康持续发展具有重要意义。当前针对城镇用地增长边界划定的研究多采用较为成熟的元胞自动机(CA)模型对城市未来格局进行模拟,且研究多集中于单一的城镇用地增长边界划定,尚无对城镇用地增长的惯性边界进行定量划定,而划定惯性边界不仅能够为城市发展预留一定的用地空间,也能提高城市规划的实施效率。对此,本文以2000、2009和2015年福州中心城区土地利用数据为基础,采用FLUS模型进行土地利用模拟,并对模型精度进行了验证(2015年土地利用模拟总体精度达到0.9389,Kappa系数达0.9165),据此预测了2027年的土地利用格局,从中提取城镇用地采取形态学的膨胀与腐蚀法(MED)进行增长边界的划定。在此基础上,本文提出了一种借鉴力学动能定理划定城镇用地增长惯性边界的方法,以坡度和地类作为摩擦力参数,对福州中心城区城镇用地增长惯性边界进行了研究。结果表明,FLUS模型和MED能够有效地对土地利用进行模拟且能较好的对城镇用地增长边界进行拟合;借鉴动能定理的方法能够根据城市不同方向的扩展阻力和各个方向的扩展强度较好地划定其惯性边界,具有现实可操作性和实际参考价值。 相似文献
17.
以小球藻(Chlorella sp. CHX-1)为实验材料,采用外切中心复合设计试验法(CCC)研究了温度(16~34 ℃)和盐度(15~45)对小球藻生长的联合效应.结果表明:温度与盐度的-次、二次效应对小球藻比生长速率都有极显著影响(P 〈 0.01),温度、盐度之间的互作效应对小球藻比生长速率影响显著(P 〈 0.05),温度的效应大于盐度的效应.响应曲面法分析发现,随着温度和盐度的升高,小球藻的比生长速率呈先上升后下降的趋势.建立小球藻生长与温度、盐度的回归模型方程,该模型的决定系数0.991 7,矫正决定系数0.985 8,表明模型的拟合度极高;模型的预测决定系数0.949 8,可用于预测小球藻比生长速率的变化.通过模型优化和验证实验,得到在温度、盐度组合为25.9 ℃/28.4 时,小球藻比生长速率达到最大值0.652,满意度为0.981. 相似文献
18.
在饲料中分别添加3.0×108kg-1(A组)、1.5×108kg-1(B组)、1.0×108kg-1(C组)的嗜酸小球菌,制成3种实验饲料,以不添加嗜酸小球菌(D组)作为对照,饲养日本鳗鲡60d,以研究嗜酸小球菌对日本鳗鲡生长和免疫的影响。测定了增重率、饵料系数、成活率、血清中一氧化氮含量以及人工感染后的死亡率,并通过电镜观察了小肠壁细胞的微绒毛结构。结果表明A、B、C组和对照组的相对增重率分别为42.31%、75.42%、89.65%和40.32%,饲料系数分别为1.93、1.12、0.98和1.58,C组的相对增重率显著高于其他组,饵料系数则显著低于其他组,成活率也显著提高。电镜观察发现C组和B组的鳗鲡小肠细胞微绒毛排列整齐、细而长,吸收面积增大,从而提高了对饲料利用率,D组鳗鲡小肠细胞的微绒毛稀疏、短,排列不均匀。血清中NO的含量A、B、C组分别比对照组提高了23%、42%和73%。C组人工感染后的死亡率显著低于其他组。实验结果表明,在鳗鲡饲料中添加嗜酸小球菌可以显著促进鳗鲡的生长,降低饵料系数,增强其免疫力。 相似文献
19.
WU Jinkui DING Yongjian WANG Genxu SHEN Yongping Yusuke YAMAZAKI Jumpei KUBOTA 《中国地理科学(英文版)》2006,16(3):243-248
1 Introduction Most of the solar radiation that ecosystem seizes is con- sumed on latent, sensible and soil heat flux. Among them, latent heat flux shares the biggest part (Gutierrez and Meizer, 1994; Ham et al., 1991; Rachidi et al., 1993). The radiation budget and the energy balance are crucial to water conversion and effective water utilization. Also, they are important parts of research of water-saving ag- riculture (Mo et al., 1997). At present, the researches on radiation budget and e… 相似文献
20.
Atlantic salmon Salmo salar were reared at four stocking densities—high density D 1(final density ~39 kg/m 3), medium densities D 2(~29 kg/m 3) and D 3(~19 kg/m 3), and low density D 4(~12 kg/m 3)—for 40 days to investigate the effect of stocking density on their growth performance, body composition and energy budgets. Stocking density did not significantly affect specific growth rate in terms of weight(SGR w) but did affect specific growth rate in terms of energy(SGR e). Stocking density significantly influenced the ration level(RL w and RL e), feed conversion ratio(FCR w and FCR e) and apparent digestibility rate(ADR). Ration level and FCR w tended to increase with increasing density. Fish at the highest density D 1 and lowest density D 4 showed lower FCR e and higher ADR than at medium densities. Stocking density significantly affected protein and energy contents of the body but did not affect its moisture, lipid, or ash contents. The expenditure of energy for metabolism in the low-density and high-density groups was lower than that in the medium-density groups. Stocking density affected energy utilization from the feces but had no effect on excretion rate. The greater energy allocation to growth at high density and low density may be attributed to reduced metabolic rate and increased apparent digestibility rate. These findings provide information that will assist selection of suitable stocking densities in the Atlantic-salmon-farming industry. 相似文献