Techniques for maturation, spawning and larval rearing of Pacific yellowtail, Seriola mazatlana, ... more Techniques for maturation, spawning and larval rearing of Pacific yellowtail, Seriola mazatlana, were developed in Ecuador during the last five years. Using the methodology described in this paper, we were able to obtain continuous and sustainable year-round spawning of both wild and captive reared broodstock fish in maturation tanks. After collection from the wild and acclimation for about one year at the hatchery facilities, one group of twelve broodstock fish was producing about 400, 000 fertilized eggs twice a week over a 18-month period. Another group of ten wild broodstock fish spawned 4, 500, 000 fertilized eggs per month from February to October, 1997. Similar results were achieved with a third group of twelve wild caught broodstock fish in another commercial hatchery in Ecuador. During 1997, 50 months after hatching, we were able to get a hatchery grown group of brood fish (first generation in captivity) to spawn about 200, 000 fertilized eggs twice a week in captivity. Larval husbandry was conducted using three different techniques: intensive, semiintensive and extensive. Results have been highly variable. Depending upon the egg quality from the different batches, survival rates ranging from 0-70% were achieved throughout larval rearing of Seriola until metamorphosis. High mortalities of fingerlings and early juveniles after metamorphosis have been lowering the average survival rates through the juvenile stage to 0.5-2.0%. Epitheliocystis has been shown to be the most important disease to occur during early developmental stages. Epizootics of this disease have caused mass mortalities of fingerlings. Other factors directly or indirectly related to the high mortality rates observed are broodstock nutrition, variability in egg quality among different batches, larval nutrition, weaning from live feeds onto artificial diets, as well as high levels of cannibalism after metamorphosis. Commercial production of Pacific yellowtail in Ecuador and other Latin American countries has been hampered exclusively by high mortalities of fingerlings and early juveniles. All other technicalities related to their aquaculture are thought to be mastered. The technological feasibility of Pacific yellowtail aquaculture has been proven. The commercial, eco-nomical viability of the operation remains uncertain.
Maturation,spawning and larval rearing techniques of pacific yellowtail,Seriola mazatlana (第2回国際学術講演会講演要旨集:水産養殖の新たなパラダイム)
水産増殖, Sep 20, 1998
Spawning and larval husbandry of flounder (Paralichthys woolmani) and pacific yellowtail (Seriola mazatlana), new candidate species for aquaculture
Aquaculture, Sep 1, 1997
... species for aquaculture Daniel D. Benetti ab'*l 11 Mariculture Project, Cinco, P. 0. Box... more ... species for aquaculture Daniel D. Benetti ab'*l 11 Mariculture Project, Cinco, P. 0. Box 10229, Guayaquil, Ecuador b Rosenstiel School of Marine and Atmospheric Science, Division of Marine Biology and Fisheries, University of Miami. 4600 Rickenbacker Causeway, Miami, FL ...
Consideracoes sobre desova e alevinagem da tainha (Mugil liza Valenciennes, 1836) em laboratorio
Base de dados : REPIDISCA. Pesquisa : 147364 [Identificador único]. Referências encontradas : 1 [... more Base de dados : REPIDISCA. Pesquisa : 147364 [Identificador único]. Referências encontradas : 1 [refinar]. Mostrando: 1 .. 1 no formato [Detalhado]. página 1 de 1, 1 / 1, REPIDISCA, seleciona. para imprimir. Id: 147364. Autor: Benetti, Daniel D; Fagundes, Eduardo B. ...
Cardiovascular performance is altered by temperature in larval fishes, but how acute versus chron... more Cardiovascular performance is altered by temperature in larval fishes, but how acute versus chronic temperature exposures independently affect cardiac morphology and physiology in the growing larva is poorly understood. Consequently, we investigated the influence of water temperature on cardiac plasticity in developing mahi-mahi. Morphological (e.g. standard length, heart angle) and physiological cardiac variables (e.g. heart rate f H , stroke volume, cardiac output) were recorded under two conditions by imaging: (i) under acute temperature exposure where embryos were reared at 25°C up to 128 h post-fertilization (hpf) and then acutely exposed to 25 (rearing temperature), 27 and 30°C; and (ii) at two rearing (chronic) temperatures of 26 and 30°C and performed at 32 and 56 hpf. Chronic elevated temperature improved developmental time in mahimahi. Heart rates were 1.2-1.4-fold higher under exposure of elevated acute temperatures across development (Q 10 ≥2.0). Q 10 for heart rate in acute exposure was 1.8-fold higher compared to chronic exposure at 56 hpf. At same stage, stroke volume was temperature independent (Q 10 ∼1.0). However, larvae displayed higher stroke volume later in stage. Cardiac output in developing mahi-mahi is mainly dictated by chronotropic rather than inotropic modulation, is differentially affected by temperature during development and is not linked to metabolic changes.
This study examined potential interactive effects of co-exposure to Deepwater Horizon (DWH) crude... more This study examined potential interactive effects of co-exposure to Deepwater Horizon (DWH) crude oil (∼30 μg L −1 ΣPAHs) for 24 h and either hypoxia (2.5 mg O 2 L −1 ; 40% O 2 saturation) or elevated temperature (30°C) on the swimming performance of juvenile mahi-mahi (Coryphaena hippurus). Additionally, effects of shorter duration exposures to equal or higher doses of oil alone either prior to swimming or during the actual swim trial itself were examined. Only exposure to hypoxia alone or combined with crude oil elicited significant decreases in critical swimming speed (U crit) and to a similar extent (∼20%). In contrast, results indicate that elevated temperature might ameliorate some effects of oil exposure on swimming performance and that effects of shorter duration exposures are either reduced or delayed.
With aquaculture steadily expanding, the need for suitable space has been followed by the develop... more With aquaculture steadily expanding, the need for suitable space has been followed by the development of more efficient, cost-effective, and environmentally sustainable methodologies. Avoiding possible conflicts between the development of commercial aquaculture operations and the environmental impact in coastal areas, utilizing the offshore environment offers the greatest potential for expansion of the industry in most regions throughout the world. Although currents and greater depths generally increase the assimilation capacity and energy of the offshore environment and offer many advantages for aquaculture, a number of challenges associated with developing any activity in the open ocean environment must be taken into consideration. This article summarizes these advantages and challenges, focusing on the first and most crucial step for project development: site selection criteria for open ocean aquaculture. Although most of the concepts and criteria are common to other marine net pen aquaculture operations, we review and present those conditions that are inherent to the open ocean environment and must be considered before developing any offshore aquaculture activity. These encompass basic premises; assumptions; logistics; infrastructure; availability of manpower, services, and materials; legal framework; socioeconomic and political issues; and oceanographic, biological, environmental, and technological criteria. There are no defined set of criteria, as most are interacting and not fixed but interdependent (e.g., depth vs. current velocity). However, suitable sites must meet basic crucial standards summarized here. Site selection is one of the most important decisions for the establishment of a fish farm operation. Satellite images, hydrographic charts, maps, Google Earth, and Geographic Information Systems can all provide important information for preliminary work on site assessment; however, a very careful in situ survey is mandatory to evaluate the suitability of the area.
Bioenergetics and growth of dolphin, Coryphaena hippurus
Metabolism, growth and energy utilization of dolphin were studied at 26$\sp\circ$C during all lif... more Metabolism, growth and energy utilization of dolphin were studied at 26$\sp\circ$C during all life stages. Experimental organisms included wild and cultured adult fish (0.9-4.2 kg) and eggs, larvae and juvenile (1.5-43 g) from $F\sb1$, and $F\sb7$ generations inbred in captivity. The mean rates of oxygen consumption (VO$\sb2$ = $\mu$l O$\sb2$ indiv.$\sp{-1}$ h$\sp{-1}$) by eggs and 1-18 day-old larvae were 0.25
Journal of the World Aquaculture Society, Sep 21, 2018
This research examined the effect of initial stocking density and feeding regime on larval growth... more This research examined the effect of initial stocking density and feeding regime on larval growth and survival of Japanese flounder, Paralichthys olivaceus. Larval rearing trials were conducted in nine 50-L tanks with different initial stocking densities combined with different feed rations (20 larvae/L with standard feed ration [LD], 80 larvae/L with standard feed ration [HD], and 80 larvae/L with four times the standard feed ration [HD+]). Larvae were stocked on 0 days posthatch (DPH) following hatching of the fertilized embryos. Larval total length (TL), survival rates, and final densities were observed on larval settlement (32 DPH) to evaluate larval rearing performance. At 32 DPH, there were no significant differences (p > .05) in TL or survival rates between the LD (46.5 AE 17.0%) and HD+ (40.3 AE 9.4%). The TL and survival rate of HD (23.1 AE 3.5%) were significantly lower than that of LD and HD+ (p < .05). However, the larval density of HD was significantly higher than that of LD (p < .05). HD+ achieved the best larvae production (32.27 AE 7.51 larvae/L), supported by sufficient food source, high water exchange, and proper water quality management (routine siphoning, surface skimming). The larval-rearing protocols and larval development from hatching to metamorphosis is described in detail, with corresponding photographs taken during the experiment.
Evaluating the potential bioextractive capacity of South Florida native macroalgae Agardhiella subulata for use in integrated multi-trophic aquaculture (IMTA)
Aquaculture
Abstract With the expansion of marine aquaculture throughout the world comes a need for solutions... more Abstract With the expansion of marine aquaculture throughout the world comes a need for solutions to improve the economic viability and environmental sustainability of farming operations. Integrated multi-trophic aquaculture (IMTA) has been identified as a promising method of farming that typically combines multiple cultured species in connected systems in an effort to decrease the concentration of nutrients expelled as waste products from intensive finfish culture while also increasing commercial profits via subsequent extractive biomass production. This study examined the effectiveness of South Florida native red macroalgal species Agardhiella subulata for use as a productive, nutrient-extracting species for IMTA in the Atlantic, Gulf of Mexico, and Caribbean regions. When cultured in a pilot-scale, land-based IMTA system for replicated 15 day trials with American red snapper, Lutjanus campechanus, A. subulata grew up to 14.4% d−1 and significantly decreased the concentration of all measured dissolved inorganic nutrients in the effluent water. The average percent (% ± SE) removal of nutrients were: 68.8 ± 4.8 ammonia, 94.5 ± 1.3 nitrate, 96.6 ± 2.0 nitrite, and 93.2 ± 3.1 phosphate from primary culture effluents. Further evidence of A. subulata fitness for commercial IMTA practices is shown through significantly high bulk nitrogen tissue concentration of experimental (nutrient-enriched) compared to control (un-enriched) groups. Results of this study demonstrate the efficient growth and nutrient removal capabilities of A. subulata when used in IMTA applications with marine finfish production in warm water environments, as may be encountered in marine aquaculture projects in the Atlantic, Gulf of Mexico and Caribbean regions.
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Sustainable Developments by Artificial Intelligence and Machine Learning for Renewable Energies
How a deepwater oil spill provided a new perspective on fish egg vertical distribution
AGU Fall Meeting Abstracts, Dec 1, 2019
Enhanced oxygen unloading in two marine percomorph teleosts
Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, 2021
Teleost fishes are diverse and successful, comprising almost half of all extant vertebrate specie... more Teleost fishes are diverse and successful, comprising almost half of all extant vertebrate species. It has been suggested that their success as a group is related, in part, to their unique O2 transport system, which includes pH-sensitive hemoglobin, a red blood cell β-adrenergic Na+/H+ exchanger (RBC β-NHE) that protects red blood cell pH, and plasma accessible carbonic anhydrase which is absent at the gills but present in some tissues, that short-circuits the β-NHE to enhance O2 unloading during periods of stress. However, direct support for this has only been examined in a few species of salmonids. Here, we expand the knowledge of this system to two warm-water, highly active marine percomorph fish, cobia (Rachycentron canadum) and mahi-mahi (Coryphaena hippurus). We show evidence for RBC β-NHE activity in both species, and characterize the Hb-O2 transport system in one of those species, cobia. We found significant RBC swelling following β-adrenergic stimulation in both species, providing evidence for the presence of a rapid, active RBC β-NHE in both cobia and mahi-mahi, with a time-course similar to that of salmonids. We generated oxygen equilibrium curves (OECs) for cobia blood and determined the P50, Hill, and Bohr coefficients, and used these data to model the potential for enhanced O2 unloading. We determined that there was potential for up to a 61% increase in O2 unloading associated with RBC β-NHE short-circuiting, assuming a - 0.2 ∆pHa-v in the blood. Thus, despite phylogenetic and life history differences between cobia and the salmonids, we found few differences between their Hb-O2 transport systems, suggesting conservation of this physiological trait across diverse teleost taxa.
Overview on advanced technologies of marine finfish aquaculture in the Americas
Rachycentron canadum (cobia) is a species that has attracted the interest of the marine fish farm... more Rachycentron canadum (cobia) is a species that has attracted the interest of the marine fish farming industry due to displaying numerous traits favorable to cultivation. The species is characterized by its large size, rapid growth, robustness and established technological support for cultivation. Cobia shows sexual size dimorphism (SSD) as adults, with females being significantly larger than males. In fish, sexual dimorphism related to morphology can be the result of ecological, functional, or adaptive selection. Methodologies that allow the application of monosex cultures increase both the biotechnological and production potential of a species. With a view to establishing parameters for early sex determination in R. canadum, morphological analyses were conducted in juveniles aged 139 days (4.6 months) using geometric morphometrics. Sexual shape dimorphism (SShD) in female cobia is expressed by an elongated body and extended space between pectoral and anal fins, suggesting fecundity-related morphological adaptations. The results are promising and indicate a high index of early sex discrimination using geometric morphometrics, demonstrating the possibility of developing routine protocols that can be applied to increase species production.
Improvement of Water Chemistry with <i>Bacillus</i> Probiotics Inclusion during Simulated Transport of Yellowfin Tuna Yolk Sac Larvae
North American Journal of Aquaculture, 2011
The effects of adding a probiotic Bacillus spp. blend on shipping bag water quality and survival ... more The effects of adding a probiotic Bacillus spp. blend on shipping bag water quality and survival of yolk sac larvae of yellowfin tuna Thunnus albacares during a 24‐h mock shipment were investigated. To better detect effects on water quality, the trial was designed without the utilization of available chemical water quality or temperature modulators. Shipping water salinity (30.7–31.0‰) and temperature (24.0–26.7°C) reflected conditions utilized during larval rearing. Probiotic incorporation (15 mL/L, about 1.5 × 106 colony‐forming units/mL) resulted in significantly lower final concentrations of total ammonia nitrogen and un‐ionized ammonia in comparison with the control. Significantly higher final mean dissolved oxygen concentration observed in the probiotic treatment could have resulted from stress reduction. Although no statistical difference was detected in larval survival upon termination of the trial, improvements in water quality (reduced total ammonia nitrogen and increased dissolved oxygen) resulting from incorporation of Bacillus probiotics would yield added levels of safety during shipping and would reduce the chances of negative results while incurring minimal increases in shipping costs.Received January 28, 2010; accepted May 1, 2010
Per uoroalkyl substances (PFAS) are highly persistent organic pollutants that have been detected ... more Per uoroalkyl substances (PFAS) are highly persistent organic pollutants that have been detected in a wide array of environmental matrices and, in turn, biota including humans and wildlife wherein they have been associated with a multitude of toxic, and otherwise adverse effects, including ecosystem impacts. In the present study, we developed a toxicity assay for embryonic stages of mahi-mahi (Coryphaena hippurus), as an environmentally relevant pelagic sh species, and applied this assay to the evaluation of the toxicity of "legacy" and "next-generation" PFAS including, respectively, per uorooctanoic acid (PFOA) and several per uoroethercarboxylic acids (PFECA). Acute embryotoxicity, in the form of lethality, was measured for all ve PFAS toward mahi-mahi embryos with median lethal concentrations (LC 50) in the micromolar range. Consistent with studies in other similar model systems, and speci cally the zebra sh, embryotoxicity in mahi-mahi generally (1) correlated with uoroalkyl chain length and hydrophobicity, i.e., log P, of PFAS, and thus, aligned with a role of uptake in the relative toxicity; and (2) increased with continuous exposure, suggesting a possible role of developmental stage speci cally including a contribution of hatching (and loss of protective chorion) and/or differentiation of target systems (e.g., liver). Compared to prior studies in the zebra sh embryo model, mahi-mahi was signi cantly more sensitive to PFAS which may be related to differences in either exposure conditions (e.g., salinity) and uptake, or possibly differential susceptibility of relevant targets, for the two species. Moreover, when considered in the context of the previously reported concentration of PFAS within upper sea surface layers, and co-localization of buoyant eggs (i.e., embryos) and other early developmental stages (i.e., larvae, juveniles) of pelagic sh species to the sea surface, the observed toxicity potentially aligns with environmentally relevant concentrations in these marine systems. Thus, impacts on ecosystems including, in particular, population recruitment are a possibility. The present study is the rst to demonstrate embryotoxicity of PFAS in a pelagic marine sh species, and suggests that mahi-mahi represents a potentially informative, and moreover, environmentally relevant, ecotoxicological model for PFAS in marine systems.
The effects of acute temperature change and digestive status on in situ cardiac function in mahi-mahi (Coryphaena hippurus)
Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, 2021
In this study, we investigated the effect of acute increases in temperature on cardiovascular fun... more In this study, we investigated the effect of acute increases in temperature on cardiovascular function of mahi-mahi (Coryphaena hippurus). We also describe, for the first time, an artery that supplies the gastrointestinal tract that originates from the fourth branchial artery. We used vascular casting to verify the anatomical location of this unique celiaco-mesenteric artery. We predicted that blood flow in this vessel would be correlated with the digestive state of the animal. Increasing water temperature from 25.0 to 30.5 °C resulted in a linear increase in heart rate (fH) from 165 ± 4 beats∙min-1to 232 ± 7 beats∙min-1. Over this temperature range, fH strongly correlated with water temperature (R2 = 0.79). At 31 °C fH no longer correlated with water temperature, and at 34 °C fH had dropped to 114 ± 19 beats∙min-1. Furthermore, we found that mahi are capable of maintaining constant cardiac output over a temperature range from 25 to 31 °C. Cardiac function appeared to be compromised at temperatures >31 °C. In fed anesthetized fish, blood flow was pulsatile in the celiaco-mesenteric artery and was not in fasted fish. In fed fish, blood flow in the left celiaco-mesenteric artery was 1.99 ± 0.78 ml·min-1·kg-1 compared to the total cardiac output of 168.6 ± 12.7 ml·min-1·kg-1. The data suggest that mahi can differentially regulate gastric blood flow based on feeding state, which may explain the high digestive efficiency and very high growth rates of these pelagic predators.
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