Efecto de la salinidad sobre la fisiología energética del camarón blanco Litopenaeus vannamei (Boone)

The energy balance was determined with in Litopenaeus vannamei, juveniles acclimated to salinity where they were hyperosmotic (20 ups), isosmotic (26 ups), and hypo-osmotic (32 ups). Also O:N atomic ratio was calculated. The ingestion rate, oxygen consumption, ammonium excretion and scope for growth were affected significantly (p < 0.05) when the organisms were acclimated at 20, 26 and 32 ups. The highest energy contained from the food consumed was obtained in the organisms maintained in 26 ups. The lowest energy expense derived to routine metabolism, and excretion of nitrogenous products was obtained in the animals maintained at 26 ups. The high quantity of energy channeled to the scope for growth (671.1 J g-1 day-1 d.w.) was obtained in the shrimps acclimated to salinity of 26 ups. The O:N atomic ratio calculated for the juveniles indicated a catabolism of carbohydrates for the organisms maintained in the isosmotic condition. The apparent heat increment, the feces production, and energy lost by exuviae, not were significantly different (p > 0.05) in the shrimps exposed to the three salinities. We recommend maintaining Litopenaeus vannamei juveniles at the salinity level which is isosmotic (26 ups), where they are free of environmental stress, these conditions for white shrimp juveniles would enhance production in the cultivation of this species.Se determinó el balance energético en juveniles de Litopenaeus vannamei, aclimatados a la salinidad como hiperosmóticos (20 ups), isosmóticos (26 ups), o hiposmóticos (32 ups). Además, se calculó la razón atómica O:N. La tasa de ingestión, el consumo de oxígeno, la excreción de amonio y el campo de crecimiento fueron afectados significativamente (p < 0.05) cuando los organismos fueron aclimatados a 20, 26 y 32 ups. La mayor cantidad de energía ingerida contenida en el alimento se determinó en los organismos mantenidos en condiciones de 26 ups de salinidad. El menor gasto energético derivado a metabolismo de rutina y la excreción de productos nitrogenados se obtuvo en los animales mantenidos con 26 ups. La mayor cantidad de energía canalizada al campo de crecimiento (671.1 J g-1 dia1 p.s.) se encontró en los camarones aclimatados a la salinidad de 26 ups. La razón O:N calculada para los juveniles indicó un catabolismo de carbohidratos para los organismos mantenidos en la condición isosmótica. El incremento de calor aparente, la producción de heces y la energía derivada hacia la formación del exoesqueleto, no fueron diferentes significativamente (p > 0.05) en los camarones expuestos a las tres salinidades. Para optimizar las condiciones de cultivo de Litopenaeus vannamei se recomienda mantener a los juveniles en la salinidad para la cual es isosmótico (26 ups), evitando el estrés ambiental, lo que desde el punto de vista fisiológico se canaliza en una mayor cantidad de energía hacia el campo de crecimiento

Fisiología energética de Cherax quadricarinatus (von Martens) alimentado con dos dietas, expuesto a un regimen constante y fluctuante de temperatura

The energy budget of the redclaw juveniles Cherax quadricarinatus feed with two diets (Rangen with 35% protein and Purina with 32%) was determined. The organisms were exposed to two regimens of temperature, constant 28 ºC and fluctuating 25-33 ºC. The highest energy from the food consumed by the organisms was obtained from the fluctuating regime of temperature and the Rangen diet. The oxygen consumption routine of the redclaw juveniles fed with both diets and exposed to the fluctuating temperature regime was 3.5 to 7.1% less than the organisms acclimated to the constant temperature regime. In the crayfish maintained with the fluctuating temperature regime the apparently heat increase (AHI) caused by the food ingestion was the lowest value. The high quantity of potential energy derived to the scope for growth (1949 Joules g-1 day-1 d.w.) was obtained in the juveniles of redclaw fed with the Rangen diet and the fluctuating regime. With the results obtained in this study we recommended in order to optimize the redclaw crayfish culture (Cherax quadricarinatus) in controlled conditions, to use a similar diet, which has the nutrients as Rangen. Also the organisms to be maintained in a fluctuating temperature regime because the exposition to this cycle allows maximizing the energy, which the crayfish will canalize for the scope of growth.El balance energético de juveniles de quelas rojas Cherax quadricarinatus alimentados con dos dietas (Rangen con 35% de proteína y Purina con 32%) se determino al exponer a los organismos a dos regímenes de temperatura uno constante 28 ºC y otro fluctuante 25-33 ºC. La mayor cantidad de energía ingerida contenida en el alimento consumido se obtuvo en los organismos alimentados con la dieta Rangen y aclimatados al régimen fluctuante de temperatura. El consumo de oxígeno de rutina de los acociles de quelas rojas alimentados con ambas dietas y expuestos al régimen fluctuante de temperatura fue de 3.5 a 7.1% menor que los aclimatados al régimen constante de temperatura. En los acociles mantenidos en el régimen fluctuante de temperatura el incremento de calor aparente causado por la ingestión del alimento tuvo el valor mas bajo. La mayor cantidad de energía derivada al campo de crecimiento (1949 joules g-1 día -1 p.s.) se obtuvo en los juveniles del acocil de quelas rojas alimentados con la dieta Rangen y expuestos al régimen fluctuante de temperatura. Los resultados de este trabajo permiten recomendar que para optimizar el cultivo del acocil de quelas rojas C. quadricarinatus en condiciones controladas, se use una dieta con los componentes nutrimentales como la Rangen y que los organismos se mantengan en un régimen fluctuante de temperatura ya que la exposición de los acociles al régimen cíclico de temperatura, permite que se maximice la energía que canalizaran al campo de crecimiento

Effect of hydrosoluble polysaccharides of Macrocystis pyrifera on physiological and metabolic responses of Litopenaeus vannamei infected with Vibrio campbellii

Adult white shrimp Litopenaeus vannamei between 23 and 32 g of wet weight were injected or submerged in a hydrosoluble polysaccharides extract from Macrocystis pyrifera and infected with Vibrio campbellii. The infection decreased the oxygen consumption rate to 24 mg O2 h-1 kg-1 w.w., in shrimps of the control group, which were only infected with V. campbellii. Immunestimulated shrimps did not decrease their oxygen consumption rate at any hour p.i. (46 mg O2 h-1 kg-1 w.w.) maintaining it similar to the pre-injection group. Glucose level in the hemolymph of V. campbellii infected shrimps at two hours p.i. was significantly higher (p > 0.05) than the level of the pre-injection group. L. vannamei injected with the extract showed a significant decrease (p > 0.05) in their glucose level at 12 hours p.i., but at 24 hours p.i. it returned to normal level. Shrimps submerged in the extract showed no significant glucose level difference (p < 0.05). Lactate concentration in the hemolymph of the pre-injection group was 11.4 mg dL-1 , but adults injected with the extract had the lowest lactate levels throughout the experiment. Shrimps submerged in the extract decreased lactate levels at 6 and 12 hours p.i. but at 24 hours p.i. the level returned to 9.0 mg dL-1 . The total protein concentration in the hemolymph of pre-injection group was 115.3 mg mL-1 , shrimp injected with saline solution showed no significant differences (p < 0.05) compared to basal control; shrimps injected with V. campbellii had the lowest values of total proteins 6 hours p.i (p > 0.05) immunoestimulated shrimps showed an increase in their total proteins levels. This study concluded that administration of extract of M. pyrifera via injection and immersion in adult white shrimp can be used for immunostimulation purposes

Comparison of Aerobic Scope for Metabolic Activity in Aquatic Ectotherms With Temperature Related Metabolic Stimulation: A Novel Approach for Aerobic Power Budget

Considering that swim-flume or chasing methods fail in the estimation of maximum metabolic rate and in the estimation of Aerobic Scope (AS) of sedentary or sluggish aquatic ectotherms, we propose a novel conceptual approach in which high metabolic rates can be obtained through stimulation of organism metabolic activity using high and low non-lethal temperatures that induce high (HMR) and low metabolic rates (LMR), This method was defined as TIMR: Temperature Induced Metabolic Rate, designed to obtain an aerobic power budget based on temperature-induced metabolic scope which may mirror thermal metabolic scope (TMS = HMR—LMR). Prior to use, the researcher should know the critical thermal maximum (CT max) and minimum (CT min) of animals, and calculate temperature TIMR max (at temperatures −5–10% below CT max) and TIMR min (at temperatures +5–10% above CT min), or choose a high and low non-lethal temperature that provoke a higher and lower metabolic rate than observed in routine conditions. Two sets of experiments were carried out. The first compared swim-flume open respirometry and the TIMR protocol using Centropomus undecimalis (snook), an endurance swimmer, acclimated at different temperatures. Results showed that independent of the method used and of the magnitude of the metabolic response, a similar relationship between maximum metabolic budget and acclimation temperature was observed, demonstrating that the TIMR method allows the identification of TMS. The second evaluated the effect of acclimation temperature in snook, semi-sedentary yellow tail (Ocyurus chrysurus), and sedentary clownfish (Amphiprion ocellaris), using TIMR and the chasing method. Both methods produced similar maximum metabolic rates in snook and yellowtail fish, but strong differences became visible in clownfish. In clownfish, the TIMR method led to a significantly higher TMS than the chasing method indicating that chasing may not fully exploit the aerobic power budget in sedentary species. Thus, the TIMR method provides an alternative way to estimate the difference between high and low metabolic activity under different acclimation conditions that, although not equivalent to AS may allow the standardized estimation of TMS that is relevant for sedentary species where measurement of AS via maximal swimming is inappropriate

Ensayo de diferentes lecitinas en la dieta de juveniles de Penaeus vannamei (Crustacea: Decapoda)

Para comparar diferentes niveles y calidades de lecitina se hizo un bioensayo nutricional con dietas isoenergéticas; para medir el crecimiento, la tasa de conversión alimenticia y sobrevivencia de juveniles de P. vannamei (290 mg ± 0.02). Las lecitinas experimentales fueron de calamar, lecitina liquida de soya (7%), lecitina desaceitada de soya (3.48%) en combinación con aceite de pescado o lípidos neutros de calamar, en una formula parcialmente desaceitada. Las cinco dietas fueron administradas ad libitum con cuatro replicas (estanques) de 15 camarones cada uno (5 x 4 x 15), durante 28 días. La mayor ganancia en peso fue (191%) y FCR (1.69±0.041) fueron obtenidos con la dieta que contenía 7% de lecitina cruda de soya como única fuente de lípidos, seguida por la dieta que contenía 3.94% de lecitina desaceitada y 2.24% de aceite Menhaiden (172% y 2.03±0.054 respectivamente). Como se esperaba los resultados menos propicios fueron con la dieta que no contenía lecitina (121% y 2.42±0.129). La lecitina cruda de soya, cubrió los requerimientos de fosfolípidos y de lípidos neutrales, tanto como la dieta con lecitina desaceitada de soya con aceite de pescado o aceite de calamar<br>The effect of different lecithin sources and presentations on growth, food conversion ratio and survival of P. vannamei (290 mg ± 0.02) was studied. The bioassay was designed in order to compare different dietary levels and different quality of lecithin. Squid lecithin, crude soybean (7%), deoiled soybean lecithin (3.48%) in combination with fish oil or squid neutral lipids, in a partially dilapidate formula. The isoenergetic diets were fed ad libitum to four replicate groups (tanks) of 15 shrimps each (5 x 4 x 15), during 28 days. The result of the bioassay with the partially dilapidate formulas was; the best growth rate (191%) and FCR (1.69±0.041) were obtained with the diet containing 7% of soybean crude lecithin as the unique lipid source. Followed by the diet countering 3.94% deoiled lecithin and 2.42% Menhaden oil (172% and 2.03±0.054 respectively). As expected, the worst results were obtained without the dietary lecithin 121% and 2.42±0.129). Crude soybean lecithin alone covered the phospholipid and neutral lipids requirements as well as the combination of deoiled soybean lecithin with fish or squid oi

Oxygen consumption, ammonium excretion and osmoregulatory capacity of Litopenaeus stylirostris (Stimpson) exposed to different combinations of temperature and salinity

The physiological responses of the blue shrimp were determined by exposing the organisms to temperatures of 23ºC, 28ºC and 33ºC, and salinities of 10, 15, 20, 25, 30, 35 and 40‰. Oxygen consumption of Litopenaeus stylirostris exposed to experimental salinities increased in direct relationship with temperature, even though at 28ºC the metabolic rate was steady. The ammonium excretion rate in juvenile shrimp acclimated at 23ºC and 33ºC was related to the pattern of osmoregulation, increasing when the shrimp were hyper-regulators and decreasing when they were hypo-regulators. The ammonium excretion rate remained constant in shrimp kept at 28ºC. The osmoregulatory capacity of the juveniles indicated that they were hypo-regulators and hyper-regulators in salinities above and below the isosmotic point, this capacity decreasing in organisms kept at 33ºC and exposed to higher salinities. The isosmotic point obtained ranged from 676.8 to 700.7 mmol kg–1 (23.7–24.6‰). The values of the slopes between the osmotic concentration of the external medium and the hemolymph of shrimp acclimated at 23ºC, 28ºC and 33ºC were 0.25, 0.17 and 0.3, respectively; the lowest value was obtained for juveniles maintained at 28ºC, being strong regulators in this condition. To optimize the culture of L. stylirostris under controlled conditions, we propose that it be cultivated in salinities of 25‰ and temperatures of 28ºC, considered the optimum conditions because in these environments the organisms are free of stress and their growth therefore increases

Anti-oxidant defence mechanisms and oxidant damage indicators measured in adults of Octopus maya exposed at optimal (24°C) and high (30°C) temperatures

There is the raw data of the evaluations of effects of temperature on males and females of Octopus maya acclimated for 30 d at 24 and 30°C. Data here are: 1. Routine metabolic rates measured in open respirometers during 24h, (RMR24h), without values, used to LMR data 2. The low oxygen consumption data (LMR) obtained from 20% lower quartile data distribution of the RMR 24h 3. High metabolic rate (HMR) measured in animals exposed to 35°C for 5 min in an intermittent respirometer. 4. Values of Q10 calculated with LMR, RMR 24h and HMR data 5. Data of activities of Catalase (CAT), superoxide dismutase (SOD), total glutathione (GSH), lipoperoxidation (LPO), Carbonylation (PO), total protein, acetyl-cholinesterase (AChE), and carboxylesterase (CbE) of hearts and muscle of males and females of O. maya. Abstract Since thermal stress enhances the energy demands, it is possible to hypothesize that the harmful effects of high temperatures observed in cephalopods are the result of the limited capacity of adults to channel more energy than those that the reproductive activity demands. In this sense, the present study was designed to know how thermal stress modulates the energy physiology of Octopus maya adults, evaluated through the relationship between temperature, respiratory metabolism (measured as thermal metabolic scope: TMS), antioxidant defence mechanisms (ANTIOX) and oxidant damage indicators (ODI). Sixty-seven males and females of O. maya were individually distributed in two different temperatures of 24, and 30°C. TMS resulted lower in females and males acclimated to 30°C than in animals maintained at 24°C. At the same time, higher values of ANTIOX and ODI were registered in the branchial hearts than in muscle arms and both octopus males and females acclimated at 30 than 24°C. Octopus Carboxyl-esterase (CbE) and acetylcholinesterase (AChE) were not affected by the acclimation temperature and by sex; however higher values in the branchial hearts than the muscle of those enzymes were observed. Results obtained in the present study demonstrated in adults of O. maya that 30°C is a temperature where animals are in a limit of energy production, probably as a result of the incapacity of animals to transport oxygen to mitochondria. Although the animals are adapted to satisfy their basic energy requirements at 30 °C, it is not enough to cover all the demands energy needed of reproduction. At 30°C, oxidative stress is present explaining the reduction in the production of eggs, viable sperm and therefore in the quality of the progeny

Thermal metabolic scope measured in adults of Octopus maya exposed at optimal (24°C) and high (30°C) temperatures

There is the raw data of the evaluations of effects of temperature on males and females of Octopus maya acclimated for 30 d at 24 and 30°C. Data here are: 1. Routine metabolic rates measured in open respirometers during 24h, (RMR24h), without values, used to LMR data 2. The low oxygen consumption data (LMR) obtained from 20% lower quartile data distribution of the RMR 24h 3. High metabolic rate (HMR) measured in animals exposed to 35°C for 5 min in an intermittent respirometer. 4. Values of Q10 calculated with LMR, RMR 24h and HMR data 5. Data of activities of Catalase (CAT), superoxide dismutase (SOD), total glutathione (GSH), lipoperoxidation (LPO), Carbonylation (PO), total protein, acetyl-cholinesterase (AChE), and carboxylesterase (CbE) of hearts and muscle of males and females of O. maya. Abstract Since thermal stress enhances the energy demands, it is possible to hypothesize that the harmful effects of high temperatures observed in cephalopods are the result of the limited capacity of adults to channel more energy than those that the reproductive activity demands. In this sense, the present study was designed to know how thermal stress modulates the energy physiology of Octopus maya adults, evaluated through the relationship between temperature, respiratory metabolism (measured as thermal metabolic scope: TMS), antioxidant defence mechanisms (ANTIOX) and oxidant damage indicators (ODI). Sixty-seven males and females of O. maya were individually distributed in two different temperatures of 24, and 30°C. TMS resulted lower in females and males acclimated to 30°C than in animals maintained at 24°C. At the same time, higher values of ANTIOX and ODI were registered in the branchial hearts than in muscle arms and both octopus males and females acclimated at 30 than 24°C. Octopus Carboxyl-esterase (CbE) and acetylcholinesterase (AChE) were not affected by the acclimation temperature and by sex; however higher values in the branchial hearts than the muscle of those enzymes were observed. Results obtained in the present study demonstrated in adults of O. maya that 30°C is a temperature where animals are in a limit of energy production, probably as a result of the incapacity of animals to transport oxygen to mitochondria. Although the animals are adapted to satisfy their basic energy requirements at 30 °C, it is not enough to cover all the demands energy needed of reproduction. At 30°C, oxidative stress is present explaining the reduction in the production of eggs, viable sperm and therefore in the quality of the progeny

Thermal biology of the sub-polar–temperate estuarine crab Hemigrapsus crenulatus (Crustacea: Decapoda: Varunidae)

Optimum temperatures can be measured through aerobic scope, preferred temperatures or growth. A complete thermal window, including optimum, transition (Pejus) and critical temperatures (CT), can be described if preferred temperatures and CT are defined. The crustacean Hemigrapsus crenulatus was used as a model species to evaluate the effect of acclimation temperature on: (i) thermal preference and width of thermal window, (ii) respiratory metabolism, and (iii) haemolymph proteins. Dependant on acclimation temperature, preferred temperature was between 11.8°C and 25.2°C while CT was found between a minimum of 2.7°C (CTmin) and a maximum of 35.9°C (CTmax). These data and data from tropical and temperate crustaceans were compared to examine the association between environmental temperature and thermal tolerance. Temperate species have a CTmax limit around 35°C that corresponded with the low CTmax limit of tropical species (34–36°C). Tropical species showed a CTmin limit around 9°C similar to the maximum CTmin of temperate species (5–6°C). The maximum CTmin of deep sea species that occur in cold environments (2.5°C) matched the low CTmin values (3.2°C) of temperate species. Results also indicate that the energy required to activate the enzyme complex (Ei) involved in respiratory metabolism of ectotherms changes along the latitudinal gradient of temperature