Oxygen consumption and ammonia excretion of juvenile pink shrimp (Farfantepenaeus paulensis) in culture: temperature effects

We evaluated oxygen consumption and ammonia excretion by juveniles of the pink shrimp Farfantepenaeus paulensis at three different temperatures (15, 20 and 25 °C). The shrimp were collected in the coastal region of Cananéia, São Paulo State, Brazil. The selected temperatures are the limits recorded in aquaculture tanks in the coastal region of Cananéia. We measured oxygen consumption and ammonia excretion as proxies for metabolic activity. Oxygen consumption and ammonia excretion increased with increasing temperature, but no change was observed at 15 and 20 °C. It is possible that within this temperature range, there is thermal independence in juvenile F. paulensis do not need to allocate additional energy to compensate for temperature changes because they are physiologically adapted for this range.     

The effects of different temperature and salinity levels on the acute toxicity of zinc in the Pink Shrimp (Farfantepenaeus paulensis)

The purpose of this study was to measure the acute toxicity of zinc (Zn) on Farfantepenaeus paulensis at different salinities and temperatures by monitoring oxygen consumption. This aspect of the effect of zinc has not been studied in this important commercial species before. First, we examined the acute toxicity of zinc in F. paulensis at 24, 48, 72, and 96?h medium lethal concentration (LC₅₀). One hundred and fifty shrimp were employed for the routine metabolism measurement utilizing sealed respirometers. Ten shrimp were subjected to oxygen consumption measurements in one of the four concentrations of zinc (control, 0.5, 1.0, 2.0, and 3.0 mg?L^?1) at three salinities (36, 20, and 5) and three temperatures (25°C, 20°C, and 15°C). Zinc was significantly more toxic at a salinity of 5 than at 20 or 36. The oxygen consumption was estimated through experiments performed on each of the 12 possible combinations of three temperatures (25°C, 20°C, and 15°C) and three salinities (36, 20, and 5). The shrimp showed a significant reduction in oxygen consumption at a salinity of 5. The results show that the oxygen consumption decreases with respect to the zinc concentration in all temperatures studied. At the highest zinc concentration employed (3.0?mg?L^?1), the salinity 5 and the temperature at 25°C, oxygen consumption decreases 60.92% in relation to the control. The results show that zinc is more toxic to F. paulensis at lower salinities. The significance of the findings for the biology of the species close to sources of zinc is discussed.     

温度和盐度突变对菲律宾蛤仔斑马蛤耗氧率和排氨率的影响

为研究温度和盐度对蛤仔新品种斑马蛤耗氧排氨的影响,以野生蛤仔为对照,实验设置15、20、25、30和35℃五个温度梯度和20、25、30、35和40五个盐度梯度,结果表明:温度和盐度对斑马蛤的耗氧率和排氨率影响显著（P < 0.05）。在温度15-35℃内,随着温度的增加,耗氧率和排氨率整体上呈增加的趋势。在20-40盐度内,耗氧率随着盐度的升高先减少后增加,排氨率随着盐度的升高先增加后减少,在盐度为30时达到最高值。在水温为15℃,盐度20-40内,斑马蛤的O:N为9.534-62.008;在盐度为35,水温在15-35℃内,斑马蛤的O:N是20.700-74.138。与野生蛤仔比较,斑马蛤的耐高温能力要强于野生蛤仔,从Q₁₀的变化反映出斑马蛤对温度的敏感性相对较弱,适应温度变化的能力比较强;斑马蛤的耐低盐和耐高盐能力强于野生蛤仔。研究结果为进一步完善蛤仔斑马蛤的人工养殖技术提供参考。     

Spermatozoa ultrastructure of the pink shrimp Farfantepenaeus paulensis (Decapoda: Dendrobranchiata)

Braga, A.L., Nakayama, C.L., Suita de Castro, L.A. and Wasielesky, W. 2011. Spermatozoa ultrastructure of the pink shrimp Farfantepenaeus paulensis (Decapoda: Dendrobranchiata). —Acta Zoologica (Stockholm) 00 : 1–6. The spermatozoa ultrastructure of the pink shrimp Farfantepenaeus paulensis was investigated in this morphological study. Spermatophores and spermatozoa were analyzed by electron microscopy. The pink shrimp spermatophore is divided into two regions: the appendage and the spermatophore main body, where spermatozoa are grouped in a spermatic mass. Pink shrimp spermatozoa are unistellate and are composed of main body and single spike. The spermatozoa body comprises a perinuclear cytoplasmic band, nucleus, acrosomal cap, and subacrosomal region. The spermatozoa cell mean total length was 10.71 μm, the mean body diameter was 5.56 μm, and the mean spike length and diameter were 5.15 μm and 0.85 μm, respectively.     

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...     

Effects of temperature and salinity fluctuation on the ammonium excretion and osmoregulation of juveniles of Penaeus vannamei,Boone

This study assesses the effect of temperature and fluctuations in salinity on the nitrogen excretion and osmoregulation of Penaeus vannamei juveniles to determine the lowest stress combination so that these can be used to optimize production of the Mexican strain in culture. The ammonium excretion rate of juveniles acclimated to 20, 24, 28 and 32°C was measured. Fluctuating salinity levels were applied to these animals in a sequence of 40%o, 33, 25, 18, 11, 18, 25, 33 and back to 40%o. The results indicate that when the salinity was reduced from 40 to 11%> the ammonium excretion of the shrimp was reduced. The osmotic concentration of the animals was hyposmotic as the salinity decreased from 40 to 25%o, hyperosmotic during the 18–11–18 in %> interval and hyposmotic as the salinity increased from 25 to 40%> again. The range of isomotic points over this range of salinity was 712–777mmol Kg^‐1. The ammonium excretion of P. vannamei exposed to these experimental conditions can be attributed to the process of osmoregulation because excretion was increased when the shrimp were hyper‐regulating and reduced when they were hypo‐regulating. Based on our results, the animals experience the lowest stress in a temperature between 27 to 30°C and a salinity close to the isosmotic point between 25 ‐ 27%o. We propose that this should prove to be the optimal temperature and salinity regime for culturing the Mexican strain of P. vannamei.     

Acute Toxicity of Arsenic under Different Temperatures and Salinity Conditions on the White Shrimp Litopenaeus vannamei

The aim of this study was to determine acute toxicity in the post larvae of the white shrimp Litopenaeus vannamei after 96 h of exposure to dissolved arsenic under three different temperatures and salinity conditions. Recent reports have shown an increase in the presence of this metalloid in coastal waters, estuaries, and lagoons along the Mexican coast. The white shrimp stands out for its adaptability to temperature and salinity changes and for being the main product for many commercial fisheries; it has the highest volume of oceanic capture and production in Mexican shrimp farms. Lethal concentrations (LC₅₀–96 h) were obtained at nine different combinations (3?×?3 combinations in total) of temperature (20, 25, and 30 °C) and salinity (17, 25, and 33) showing mean LC₅₀–96 h values (±standard error) of 9.13?±?0.76, 9.17?±?0.56, and 6.23?±?0.57 mgAs?L^?1(at 20 °C and 17, 25, and 33 salinity); 12.29?±?2.09, 8.70?±?0.82, and 8.03?±?0.59 mgAs?L^?1 (at 25 °C and 17, 25, and 33 salinity); and 7.84?±?1.30, 8.49?±?1.40, and 7.54?±?0.51 mgAs?L^?1 (at 30 °C and 17, 25, and 33 salinity), respectively. No significant differences were observed for the optimal temperature and isosmotic point of maintenance (25 °C–S 25) for the species, with respect to the other experimental conditions tested, except for at 20 °C–S 33, which was the most toxic. Toxicity under 20 °C–S 33 conditions was also higher than 25 °C–S 17 and 20 °C (S 17 or 25). The least toxic condition was 25 °C–S 17. All this suggests that the toxic effect of arsenic is not affected by temperature changes; it depends on the osmoregulatory pattern developed by the shrimp, either hyperosmotic at low salinity or hiposmotic at high salinity, as observed at least on the extreme salinity conditions here tested (17 and 33). However, further studies testing salinities near the isosmotic point (between 20 and 30 salinities) are needed to clarify these mechanisms.     

Toxic effect of DDT and endosulfan in white shrimp postlarvae Litopenaeus vannamei (Decapoda: Penaeidae) from Chiapas, Mexico

We analized acute toxicity in white shrimp (Litopenaeus vannamei) postlarvae exposed to two chlorinated pesticides, DDT and endosulfan, under laboratory conditions during 168 hours, with controlled temperature (29 +/- 1 degrees C), salinity (3 +/- 1%o) and pH (8 +/- 1). Median lethal concentrations (LC50), "incipient" LC50, median lethal time (LT50) the "maximum acceptable concentration of the toxic compound" (MACT) and "the safety level" (SL) were determined. The concentration of the compounds at which organism growth was reduced by 5 and 50% (EC5 and EC50), as well as changes in oxygen consumption patterns were determined in the surviving postlarvae. They were very sensitive to both compounds and DDT was thrice as toxic as endosulfan. Growth rate decreased 50% and 80% with endosulfan and DDT, respectively, at the experimental pestice concentration. The low resistance of postlarvae to DDT and endosulfan suggests that additional inflow of these pesticides into the aquatic system could affect the rate of shrimp production in the area.     

Effects of salinity on physiological conditions in juvenile common snook Centropomus undecimalis

This study describes the effects of different salinities on oxygen consumption, ammonia excretion, osmotic pressure, apparent heat increment, postprandial nitrogen excretion, and oxygen:nitrogen ratio in juvenile common snook Centropomus undecimalis. Oxygen consumption of fish fasting and fish feeding was statistically different in relation with salinity. Fish maintained at 0, 25, and 35 ppt invested more energy processing feed than fish maintained at 12 ppt. Fasting fish had lower ammonia excretion than feeding fish and excretion was reduced at high salinities. Snook can change the energetic substrate in function with salinity, from a mixture of protein and lipids and carbohydrates at 35 ppt to a more acute preference for proteins at lower salinities. This species changes osmotic plasma concentrations at extreme experimental salinities. The different salinities were the snook inhabits (0-36 ppt), have a direct effect on the physiology, inducing changes on the oxygen consumption, nitrogen excretion, changes on the energetic substrate and plasma osmotic pressure.     

Excretion and respiration rates of Neomysis integer (Mysidaceae): effects of temperature,sex and starvation

The combined effects of temperature, sex and length of pre-experimental starvation period on respiration, ammonia and inorganic phosphate excretion of the mysid shrimp Neomysis integer were studied in laboratory experiments. Of these variables, temperature had the strongest effect. A rise in experimental temperature from 6 to 16 °C increased the metabolic rates by a factor of 2 to 3.Weight-specific respiration rates of females were slightly lower than those of males. However, these differences could be attributed to differences in size. Sex did not significantly affect ammonia and inorganic phosphate excretion.A prolongation of the pre-experimental starvation period from 6 to 30 h reduced ammonia excretion of Neomys integer, but had no impact on oxygen consumption rates. Accordingly, the atomic O : N ratio increased in starved specimens. There were no discernables effects of the variables studied on atomic O : P and N : P ratios.     

Review of salinity effects on abundance,growth, and survival of nearshore life stages of pink shrimp (Farfantepenaeus duorarum)

The pink shrimp (Farfantepenaeus duorarum) has been selected as an ecological indicator to assess ecological effects on estuaries of implementation of the Comprehensive Everglades Restoration Plan that seeks to restore historical freshwater flows and nearshore salinity regimes in southern Florida. Concern over altered freshwater delivery impacts on pink shrimp productivity was expressed as early as the 1960s. The present review assessed pink shrimp scientific literature of the past 75+ years (>500 publications) to glean information relevant to understanding potential influence of freshwater management on pink shrimp productivity. The review was organized around “Essential Fish Habitat” metrics concerning abundance, growth, survival, distribution, productivity, and behavior. It summarizes previous pink shrimp field, laboratory, and modeling studies. Where possible, statistical analyses and meta-analyses of previously published data were performed to investigate consistency among independent findings. Pink shrimp occur in a wide range of salinities (0.5–67 ppt). A majority of studies (53.3%) reported maximal abundance between ∼20 to 35 ppt salinities. One laboratory study reported maximal growth at 30 ppt. Meta-analysis of reported growth rates did not yield results due to non-convergence of regression models. Reported survival was maximal at ∼30 ppt and remained high (>80% survival) across salinities of ∼15 to 40 ppt. A regression model that combined survival data across studies confirmed a previously reported parabolic relationship between salinity and survival; in this regression, 35 ppt maximized survival. Productivity, conditional upon survival and growth, was maximized at polyhaline (18–30 ppt) conditions. Inshore hypersalinity (>40 ppt) may elicit young pink shrimp behavioral cues counterproductive to settlement in nearshore areas. Virtually no information exists regarding postlarval pink shrimp movement or preference relative to salinity gradients. Realization and preservation of nearshore polyhaline conditions and elimination of hypersalinity should maximize growth, survival, and density, thus improving pink shrimp productivity. New and updated statistical models predicting pink shrimp distribution, abundance, growth, survival, and productivity relative to salinity conditions are needed to better guide freshwater management decisions.     

Oxygen consumption and ammonia excretion rates in Octopus maya,loligo forbesi and Lolliguncula brevis (Mollusca: Cephalopoda)

Oxygen consumption and ammonia excretion rates were investigated in young Octopus maya (hatching to 139 days old; 0.11–81.23 g wet body weight, BW; 22.5–23.9°C), young squids of Loligo forbesi (hatching to 45 days old; 9.4–115.3 mg BW; 12.3–13.1°C) and young squids of Lolliguncula brevis (2.00–39.98 g BW; 23.8–24.7°C). Except at hatching, oxygen consumption and ammonia excretion rates on an individual basis (M) of these three cephalopods increased linearly with increasing body weight (BW) expressed as M = aBW^b . Values of b for oxygen consumption were 0.900, 0.910 and 0.848 and for ammonia excretion were 0.744, 0.809 and 0.751 for O. maya, L. forbesi and L. brevis, respectively. Among the three species the value a varied widely, while b was similar for both oxygen consumption and ammonia excretion rates. Based upon these data, metabolism for hatchlings of O. maya and L. forbesi was estimated to be relatively lower than that of older juveniles. The O/N ratios for hatchlings of O. maya and L. forbesi were relatively high and indicate an apparent dependence upon lipids in the immediate post‐hatching period, followed by standard protein energy utilization thereafter.     

Respiration and ammonia excretion of the shrimpCrangon crangon L.: Metabolic response to prolonged starvation

Summary Oxygen consumption and ammonia excretion were measured simultaneously in 25 individual shrimps (C. crangon) every two days during a 30-day imposed starvation.The first response to starvation was a 10% decrease in O₂ consumption and a 25% decrease in ammonia excretion. Following this, O₂ consumption decreased sharply while ammonia excretion tended to rise. From the 14th day until the end of the experiment, the rates of each remained steady, the respiratory rate being about 60% below and rate of excretion about 30% above control values.From the O:N ratio it appeared that carbohydrate reserves were quickly exhausted (3–4 days) and that lipids and proteins were the main substrates oxidized to meet the energetic requirements ofC. crangon. After 2 weeks of starvation the O:N ratio remained constant near a value of 8, indicating that only proteins were being utilised; a 50% loss of body protein after 30 days suggested that structural proteins were heavily catabolized. The meatabolic response ofCrangon to starvation (although seasonal variations must be considered) appears to depend mainly on high nitrogen requirements.     

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.     

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.     

Accumulation of urea in the haemolymph and ammonia excretion of Penaeus japonicus exposed to ambient nitrite

Penaeus japonicus (15.7 ± 1.4 g) were exposed individually in 30 ppt seawater to 0.01 (control), 5, 10, 20 and 50 mg/l nitrite-N for 24 hr. Haemolymph ammonia, urea, nitrite and whole shrimp ammonia-N excretion and nitrite-N uptake were then determined. Ammonia excretion of P. japonicus increased with increased ambient nitrite, and with a concomitant decrease of haemolymph ammonia, as occurring increased concentrations of nitrite. Concentrations of nitrite-N and urea-N in the haemolymph of shrimp increased with increased ambient nitrite-N. However, no urea-N excretion was observed for shrimp exposed to any nitrite treatments.     

阿特拉津和林丹对紫贻贝生长与繁殖净能的影响

本研究评估了亚致死浓度的林丹(1/2的60dLC50,0.935mg/L)和阿特拉津(1/2的60dLC50,3.585mg/L)对海洋性贝类影响的生理学反应。林丹和阿特拉津是已被公认的环境污染物质。56d的实验表明,这两种农药在贝类体内具有积累作用,而且在体内各器官的积累程度与其作用的靶器官相一致。林丹在体内的积累浓度(每克干重372μg)比阿特拉津(每克干重137μg)更高。该贝类在林丹中暴露56d,其氧的消耗比对照组降低10%,而在阿特拉津中则比对照组提高了29%。经林丹和阿特拉津暴露后,增加了氨排泄物。但是,两种农药均使贝类的取食率和吸收率下降。林丹会降低贝类的取食率、氧消耗、氨排泄、食物吸收率以及生长范围。在形式上,阿特拉津对贝类的影响与林丹的影响有不同之处,它会降低贝类的取食率和食物吸收率,但与林丹不同的是,它会提高贝类的氧消耗和氨排泄。总之,阿特拉津会明显地减小贝类繁殖净能。因此,阿特拉津暴露与林丹暴露的毒性症状是一致的。结合组织化学分析,贝类的生理学反应可作为一种理想的环境监测工具。研究结果表明,在二分之一的半致死浓度下暴露两个月,不仅能有效地证明林丹和阿特拉津在贝类组织内具有积累作用,而且对这些积累能产生生理反应。     

卵形鲳鲹幼鱼耗氧率和排氨率的初步研究

运用封闭流水式实验方法对不同体重和放养密度的卵形鲳鲹(Trachinoms ovatus)幼鱼耗氧率和排氨率进行了初步的研究。结果表明,卵形鲳鲹幼鱼的耗氧率随着鱼体重的增加而逐渐下降,排氨率总体上也呈降低的趋势,体重对卵形鲳鲹耗氧率、排氨率的影响均达到显著水平(P0.05);光照对卵形鲳鲹幼鱼的耗氧率和排氨率影响非常显著(P0.01),幼鱼在遮光条件下的耗氧率和排氨率分别比在自然光照条件下要低25.18%～40.76%和16.28%～40.28%;随着放养密度的增加,卵形鲳鲹幼鱼的耗氧率逐渐降低,排氨率随着密度的增加呈先上升后下降的趋势,放养密度对卵形鲳鲹耗氧率、排氨率的影响均达到显著水平(P0.05)。卵形鲳鲹的耗氧率和排氨率具有明显的昼夜变化,白天的耗氧率和排氨率均高于夜间值,耗氧率的低谷值为高峰值的69.68%,排氨率的低谷值为高峰值的30.91%。卵形鲳鲹幼鱼的窒息点溶解氧含量为(0.991±0.058)mg/L。     

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.     

Oxygen consumption and ammonia excretion of herbivorous chironomid larvae in Lake Balaton

The oxygen consumption and ammonia excretion of a herbivorous midge larva,Chironomus sp., inhabiting Lake Balaton was measured at two different temperatures. The loss of energy through respiration and that through ammonia excretion were calculated. The daily respiratory energy loss amounted to 655.5 ± 123.8 J g^–1 at 17 °C and to 1 160.0 ± 168.4 J g^–1 (dry weight) at 25 °C. Mean energy loss through ammonia excretion was about 40% less than through respiration.