Edgar Zapata Vívenes

Universidad Técnica de Manabí (UTM) · Departamento de Acuicultura Pesca y Recursos Naturales Renovables

Polychaetes, Eurythoe complanata, from the Gulf of Cariaco,Venezuela, were exposed to 0.3, 1.6, and 3.3% water-soluble fraction (WSF) of used crankcase oil during 15 and 21 days. The antioxidant enzymes glutathione peroxidase (GPX), glutathione reductase (GR), catalase (CAT), and glutathione-S-transferase (GST) were assayed in the body wall tissue....

We evaluated the capacity of metallothioneins (MT) in maintaining anaerobic metabolism in the green lipped mussel Perna viridis during experimentally induced oxidative stress. Mussels were exposed to 50 μg/L of cadmium during seven days, followed by recuperation in the sea during 35 days. Other groups of cadmium pre-exposed organisms and their resp...

La fagocitosis es una respuesta celular de primera línea mediada por células especializadas denominadas celomocitos-amebocitos. Este proceso permite englobar partículas extrañas o microorganismos, los cuales son eliminados a través de la generación de especies reactivas del oxígeno (ERO). Con la finalidad de evaluar el sistema de defensa antioxidan...

Antioxidant defenses, lipid peroxidation and endogenous energy substrates in black sea urchin Echinometra lucunter during gonadal development.Antioxidant substances (glutathione reduced-GSH, total thiols -SH, catalase activity-CAT), lipid peroxidation (TBARS) and endogenous energetic substrates (protein, carbohydrate and lipid) were determinedfrom...

Used vehicle crankcase oils are a source of contamination in Caribbean marine environments and may alter the oxidative balance of organism that inhabiting coastal ecosystems. This paper aims to evaluate effects of a water-soluble fraction of used vehicle crankcase oils (WSF-UVCO) on the antioxidant responses of the flame scallop Ctenoides scaber. T...

The effect of exposure to water-soluble fractions of used automobile crankcase oils (WSF-AUCO) on haematology parameters, immune system, stability of lysosomal membranes of hemocytes and lipid peroxidation in the digestive gland of the pearl oyster Pinctada imbricata was evaluated in this study. The oysters were exposed to 0, 1, 10 and 20 % v/v of...

Un estudio reciente realizado en Ecuador, el cual compara la calidad de larvas del camarón Penaeus vannamei, inicialmente alimentadas con microalgas producidas con luces LED y con luces fluorescentes, comprueba un notable rendimiento de las larvas alimentadas con microalgas producidas con luces LED.

Atlantic pearl oyster Pinctada imbricata is a bivalve with high potential for cultivation in tropical and subtropical environments. In this study, P. imbricata energetic metabolism was analyzed throughout a culture cycle at Gulf of Cariaco, Venezuela. Juvenile individuals (shell length 27.40 ± 2.70 mm) were cultured in a long line at 3 m depth betw...

Abrupt drops in salinity that occur in tropical estuaries during the equatorial rainy season led to hyposaline conditions which may reduce the populational density of oysters. To assess the effect of saline stress on physiological and metabolic responses of the Manabi oyster (Crassostrea cf. corteziensis) was exposed to 35, 30, 20,10 and 5‰ concent...

La extracción activa del erizo de mar Lytechinus variegatus en el noreste de Venezuela podría conllevar a una reducción de su densidad poblacional. Por consiguiente, el conocimiento sobre el crecimiento somático y la producción gonadal es de importancia para la explotación racional y el manejo sustentable de sus poblaciones. Durante un ciclo anual,...

Atlantic pearl oyster Pinctada imbricata is a bivalve with high potential for cultivation in tropical and subtropical environments. In this study, P. imbricata energetic metabolism was analyzed throughout a culture cycle at Gulf of Cariaco, Venezuela. Juvenile individuals (shell length 27.40 ± 2.70 mm) were cultured in a long line at 3 m depth betw...

Active extraction of sea-urchin Lytechinus variegatus from the northeast of Venezuela could cause a reduction in the populational density. Therefore, knowledge about somatic growth and gonadal production is relevant for the rational exploitation and sustainable management of sea-urchin populations. During an annual cycle, this study examined the re...

The nutritional quality of microalgae used as feed in larviculture is essential to improve shrimp production. Penaeus vannamei larvae were fed with the microalga Thalassiosira pseudonana produced with irradiation by light-emitting diode (LED) or fluorescent lights and evaluated for survival, weight, and molting time from Nauplius V to Zoea III. At...

The nutritional quality of microalgae used as feed in larviculture is essential to improve shrimp production. Penaeus vannamei larvae were fed with the microalga Thalassiosira pseudonana produced with irradiation by light-emitting diode (LED) or fluorescent lights and evaluated for survival, weight, and molting time from Nauplius V to Zoea III. At...

Tras un gran esfuerzo organizativo, en el XI Foro Iberoamericano de los Recursos Marinos y la Acuicultura, XI FIRMA 2021 online, se presentaron y discutieron temas de gran relevancia con exposiciones de más de 60 especialistas en el área de los recursos acuáticos y la acuicultura, con 7 conferencias magistrales y 12 sesiones de discusión. Esto perm...

The nutritional quality of microalgae used as feed in larviculture is essential to improve shrimp production. The shrimp Penaeus vannamei (zoea) larvae were fed with the microalga Thalassiosira pseudonana produced with light-emitting diode-LED or fluorescent lights irradiated and evaluated for survival, weight, and molting time from Nauplius V to Z...

In the search for complementary diets to improve performance in bivalve farming, the use of terrestrial plants with nutritional and nutraceutical properties has been proposed as an alternative. The effectiveness of moringa leaf meal Moringa oleifera (Mo) was evaluated under controlled laboratory conditions (30 days), as a dietary supplement during...

The mangrove cockle (Anadara tuberculosa) is considered overharvested. Therefore, its spat production in hatchery is needed for aquaculture and restocking of natural banks. However, larval settlement and metamorphosis are critical phases that need to be further explored. The use of different substrates on the settlement and two photoperiods on spat...

In this work we studied the health status of wild populations of the black shell Ana-dara tuberculosa, haemocyte parameters (viability, total and differential count, ly-sosomal stability, osmotic fragility) and blood chemistry (haemoglobin-Hb, proteins, triglycerides, glucose, lactate dehydrogenase-LDH and catalase-CAT). Haemolymph was extracted fr...

The used automobile crankcase oils are potential sources of contaminant elements for the coastal-marine ecosystems, affecting mainly the immunological system of organisms that feed by filtration, e. g. scallops. This study examined the effects of a water-soluble fraction of used automobile crankcase oils (WSF-UACO) on innate cellular- and humoral i...

The water used in aquaculture requires excellent microbiological quality, in order to guarantee a successful production. Some methods of treatment such as filtration, chlorination, UV-light among others, are frequently used in the aquaculture industry, which is expensive and may generate toxic compounds. In order to search for alternative methods t...

This study aims to evaluate whether taurine (an antioxidant amino acid) is able to protect developing rat skeletal muscle from the cytotoxic effects of postnatal hyperoxia. For this, two groups of newborn Sprague-Dawley strain rats were exposed to hyperoxia together with their mother, from birth until day P6, P9 and P12. The mother of one group dra...

Tropical estuaries have been considered excellent environments to develop the oyster culture Crassostrea gigas; however, there are limiting factors during the rainy season that modulate changes in physiological and cellular responses, which affect oyster survival. In this study, cellular and immunological biomarkers, growth and survival of C. gigas...

Moringa (Moringa oleifera L.) is an arboreal species native to India, adaptable to various climates. This species provides benefits for human health as it is a source of vitamins, minerals and polyunsaturated fatty acids, although its use in aquaculture is scarce. In this research, the lipid and amino acid profiles of dehydrated moringa leaf meal w...

The sea urchin Arbacia stellata can be found within estuarine ecosystems, but the critical salinity in the initial stages of life for its cultivation is unknown. Therefore, the percentage of fertilization, embryonic development and survival of A. stellata was evaluated in four salinities (ups): 5, 10, 20 and 32 (control). Gametes were obtained from...

El erizo de mar Arbacia stellata puede habitar en ecosistemas estuarinos, pero se desconoce la salinidad crítica en las etapas iniciales de vida para su cultivo. Para ello se evaluó el porcentaje de fertilización, desarrollo embrionario y supervivencia de A. stellata en cuatro salinidades (ups): 5, 10, 20 y 32 (control). Los gametos se obtuvieron d...

La moringa (Moringa oleifera L.) es una especie arbórea originaria de la India, adaptable a diversos climas. Esta especie otorga beneficios para la salud humana por ser fuente de vitaminas, minerales y ácidos grasos polinsaturados, aunque su uso acuícola es escaso. En esta investigación se analizó el perfil lipídico y aminoacídico de harina de hoja...

Echinometra lucunter (Echinometriae) is an echinoid with potential for cultivation in Venezuela that, in the northeastern region of the country, it is subject to environmental variability caused by coastal upwelling and stratification. The use of physiological indices such as the filling index and the condition index (Kn), allows to quickly know th...

Marcadores de estrés oxidativo e índices moleculares (ARN: ADN y Proteína: ADN) en Donax denticulatus (Linné, 1758) colectado en zonas impactadas post-derrame petrolero Markers of oxidative stress and molecular indices (ARN: ADN y Protein: ADN) in Donax denticulatus (Linné, 1758) collected in impacted areas post-oil spill RESUMEN | Se evaluó el est...

The sea urchin Lytechinus variegatus is considered a good candidate for aquaculture, but bacterial diseases are a major challenge in culture conditions. The innate immunological defenses of L. variegatus to bacterial challenges were assessed through hematology parameters, in vitro phagocytosis, lysozyme activity and total plasma protein concentrati...

Within the framework of the generation of research studies in applied biology for the diversification of aquaculture in Ecuador, the native sea urchin Arbacia stellata was considered with potential for its aquaculture and extraction of macroenergetic biomolecules usable for the nutraceutical and pharmaceutical industries. A total of 150 sea urchins...

En el marco de la generación de estudios de investigación en biología aplicada para la diversificación de la acuicultura en Ecuador, se consideró al erizo de mar nativo Arbacia stellata con potencial para su acuicultura y extracción de biomoléculas macroenergéticas utilizables para las industrias nutracéutica y farmacéutica. Se recolectaron 150 eri...

Las variaciones físico-químicas pueden perturbar los mecanismos de defensa inmune innatos en ostras (Chainy et., 2016), vinculados a la acción de hemocitos, responsables del reconocimiento, fagocitosis y eliminación vía degradación enzimática de microorganismos o material invasor foráneo (Canesi et al., 2002; Fisher, 1986) y producción de especies...

Effect of LED and fluorescent lights on growth and biomass of Thalassiosira pseudonana (Cleve, 1873) Resumen En búsqueda de mejorar la producción de la microalga Thalassiosira pseudonana, utilizada frecuentemente como alimento para larvas y juveniles de diversas especies de interés acuícola, en este estudio se evaluó la incidencia de diodos emiso...

La formación de la larva prima fue observada entre las 18-19 h posterior a la fertilización en los tratamientos de 32 y 20 UPS, respectivamente. Un retardo en su formación fue encontrado a bajas salinidades (<10 UPS), con una concomitante reducción de la supervivencia, especialmente a 5 UPS. Los resultados muestran escasa supervivencia de los estad...

Los objetivos del Foro Iberoamericano de los Recursos Marinos y la Acuicultura (FIRMA) siempre han constituido un reto para la organización en cualquier país donde se ha desarrollado, y siempre un puñado de voluntades ha generado, junto con los participantes, una ola académica llena de hermandad que ha conllevado al éxito, el IX FIRMA Manabí, 2019,...

To evaluate the levels of heavy metals (Cd, Pb, Cu y Zn) in edible tissue, as well as some molecular biomarkers of oxidative stress, in the digestive gland of the triagonal clam Tivela mactroides from Caicara beach (Venezuela) during different pluviometric seasons, we proceeded to collect between 90 and 100 organisms during August and December 2007...

Dunaliella salina (Chlorophyceae) es una microalga que contiene un porcentaje considerable de pigmentos, en especial acumula niveles significativos de β-carotenos; compuestos que poseen alto poder antioxidante. En esta investigación, se evaluó la capacidad antioxidante de un aceite vegetal de soya enriquecido con D. salina. La biomasa de una cepa h...

Palabras clave aceite antioxidante β-caroteno microalga Keywords oil antioxidant β-carotene microalgae RESUMEN | Dunaliella salina (Chlorophyceae) es una microalga que contiene un porcentaje considerable de pigmentos, en especial acumula niveles significativos de β-carotenos; compuestos que poseen alto poder antioxidante. En esta investigación, se...

Cell viability, total coelomocytes count (TCC), phagocytosis and lysozymes activity, lysosomal membrane stability, and micronucleus frequency were determined in coelomocytes of the polychaete Eurythoe complanata exposed to 3% of water-soluble fraction of crankcase oil (WSFCO) or to 200 µg Cd/L, during 21 days. Additionally. Body mass and molecular...

Some antioxidant responses and molecular index of growth (protein:DNA and RNA:DNA) were determined in the polychaete Eurythoe complanata collected from Gulf of Cariaco (Venezuela) during December 2009 (26.03 ± 0.64°C), February (23.96 ± 0.67°C), June (27.82 ± 0.50°C) and October 2010 (29.93 ± 0.37°C). Also, the number of individuals with signs of t...

Biochemical biomarkers are widely used for the monitoring environmental quality since they can act as early warning signals, for potential ecosystem degradation caused by contaminants. In order to investigate the acute and chronic effects of a commercial formulation of glyphosate on antioxidant defenses (glutathione peroxidase, GPx; glutathione-S-t...

Some antioxidant responses and molecular index of growth (protein:DNA and RNA:DNA) were determined in the polychaete Eurythoe complanata collected from Gulf of Cariaco (Venezuela) during December 2009 (26.03 ± 0.64°C), February (23.96 ± 0.67°C), June (27.82 ± 0.50°C) and October 2010 (29.93 ± 0.37°C). Also, the number of individuals with signs of t...

Some antioxidant responses and molecular index of growth (protein:DNA and RNA:DNA) were determined in the polychaete Eurythoe complanata collected from Gulf of Cariaco (Venezuela) during December 2009 (26.03 ± 0.64°C), February (23.96 ± 0.67°C), June (27.82 ± 0.50°C) and October 2010 (29.93 ± 0.37°C). Also, the number of individuals with signs of t...

The cadmium (Cd) bioaccumulation on metallothioneins (MT), total proteins (TP), sulfhydryl groups (-SH) and tiobarbituric acid reaction substances (TBARS) levels were determined in medium-anterior (MA) and medium-posterior (MP) corporal regions of the earthworm Eisenia andrei. The organisms were exposed to concentrations of 0; 2.50 and 10.30 mg Cd/...

The effects of malathion and chlorpyrifos on immune responses of Eisenia sp. were assessed using standard toxicity assays. In plastic containers with natural soils as substrate, mature sexually earthworms were exposed to malathion (300 mg kg-1of soil) and chlorpyrifos (300 mg kg-1of soil) during 7 and 21 days. After exposure periods, cellular viabi...

Several species of sea urchins are a potential resource for the production of gonads for consumption in Venezuela. We studied the gametogenic cycle and the gonadosomatic index (GSI) of the rock boring urchin Echinometra lucunter between June 2010 and November 2011 in northeastern Venezuela (Isla Lobos, Península de Araya and Turpialito, Gulf of Car...

Echinometra lucunter is relatively abundant in the Venezuela coast, however no details are known about its diet. We compare the stomach contents and repletion index of E. lucunter with macroalgae available in their environment (June 2010-August) and the nutrient cycle at the Golfo de Cariaco. Seventy-one species of macroalgae were identified: Rhodo...

Echinometra lucunter is relatively abundant in the Venezuela coast, however no details are known about its diet. We compare the stomach contents and repletion index of E. lucunter with macroalgae available in their environment (June 2010-August) and the nutrient cycle at the Golfo de Cariaco. Seventy-one species of macroalgae were identified: Rhodo...

Several species of sea urchins are a potential resource for the production of gonads for consumption in Venezuela. We studied the gametogenic cycle and the gonadosomatic index (GSI) of the rock boring urchin Echinometra lucunter between June 2010 and November 2011 in northeastern Venezuela (Isla Lobos, Península de Araya and Turpialito, Gulf of Car...

Este estudio evaluó el efecto de dosis subletales de cadmio (Cd) sobre los niveles de zinc (Zn), ácido gamma aminobutírico (GABA), glicina, glutamato, taurina, peroxidación de lípidos de membrana y actividad de lactato deshidrogenasa (LDH) en la retina de ratas macho, Sprague-Dawley. Se emplearon cuatro grupos de ratas: uno de control y tres tratad...

Used crankcase oil of automobiles is a potential source of hazardous contaminants, which upon reaching coastal ecosystems may affect adversely the biota. The bivalve associated to coralline reefs have been recognized as biological sensors to assessing the impact of stressing chemical substances in these marine ecosystems by means of use of biomarke...

Se estimó la sobrevivencia a la anoxia del mejillón verde Perna viridis después de siete días de exposición a 50 μg L-1 de cadmio (Cd), seguido de un período de recuperación en el mar durante 21 días. En la glándula digestiva de los organismos experimentales se determinó los niveles de Cd acumulados, y marcadores de estrés oxidativo tales como: met...

The survival to anoxia was measured from green-lipped mussel Perna viridis after of exposure to 50 μg L-1 cadmium (Cd) during seven days, followed by a recuperation period in the sea during 21 days. The levels of Cd, and oxidative stress biomarkers as metallothioneins (MT), reduced glutathione (GSH) and lipid peroxidation (TBARS), and maximal activ...

The green mussel Perna viridis has been used as a sentinel organism in marine and coastal ecosystem health assessments. In this study the degree of contamination at three sites on the coast of Sucre State (Venezuela) was analyzed using molecular, cellular, and immunological biomarkers in P. viridis. Specimens were collected from Chacopata-Guayacán...

The green mussel Perna viridis has been used as a sentinel organism in marine and coastal ecosystem health assessments. In this study the degree of contamination at three sites on the coast of Sucre State (Venezuela) was analyzed using molecular, cellular, and immunological biomarkers in P. viridis. Specimens were collected from Chacopata-Guayacán...

The green mussel Perna viridis has been used as a sentinel organism in marine and coastal ecosystem health assessments. In this study the degree of contamination at three sites on the coast of Sucre State (Venezuela) was analyzed using molecular, cellular, and immunological biomarkers in P. viridis. Specimens were collected from Chacopata-Guayacán...

This work concerns the effects of cadmium exposure on the anaerobic and oxidative metabolism in tissues of the hypoxia-tolerant green mussel Perna viridis from Venezuelan coastal waters. The mussels were exposed to different Cd concentrations (0, 20, 40 and 60 mu g/L Cd) for 7 days, and were subsequently exposed to anoxia. Prior to anoxia exposure....

This work concerns the effects of cadmium exposure on the anaerobic and oxidative metabolism in tissues of the hypoxia-tolerant green mussel Perna viridis from Venezuelan coastal waters. The mussels were exposed to different Cd concentrations (0, 20, 40 and 60 mg/L Cd) for 7 days, and were subsequently exposed to anoxia. Prior to anoxia exposure, C...

We determined the relationship among concentrations of mercury (Hg), total proteins (TP) and thiol groups (-SH), in blood of 60 school-age children, in the city of Cumaná, Venezuela. In Addition, clinical and nutritional data were recorded for each child. Mercury concentrations were determined by cold vapor atomic absorption spectrophotometry, TP c...

We compared the ichthyofauna in two distinct reef ecosystems, one with rocky coralline substrate (stony) and another structured with soft corals (octocorals). Visual counts were made along 40 m x 2 m transects, identifying all species observed. A total of 5,655 individuals in 32 families and 84 species were censused in the two reefs. Eighty species...

Resumen. Se evaluó la ictiofauna presente en dos ecosistemas de arrecifes, uno de sustrato rocoso-coralino (pétreo) y el otro estructurado por corales blandos (octocorales). Se aplicaron censos visuales sobre transeptos de 40 m x 2 m, identificando todas las especies observadas. Se censó un total de 5.655 individuos entre los dos arrecifes evaluado...

With the aim of investigate the acute effects of two concentrations (25 and 100%) of orimulsion (80:30; 70:20) and No. 6 fuel oil-water–accommodated fraction (OWAF) on antioxidant enzyme activities and immunological responses, fishes Thalassophryne maculosa were sampled from the La Restiga Lagoon, Margarita island, in eastern Venezuela. The antioxi...

Polychaetes exposed to 0.4 mg Cu +2 L -1 (2.14 mg CuSO4 5H2O L -1 ; 30% 96 h-LC50) for seven days and control individuals were divided into three groups: the first two were sensitized and non-sensitized with Micrococcus lysodeikticus, and the third was sensitized with heat-killed yeast. Lysozyme activity was tested in the first two groups and phago...

Polychaetes exposed to 0.4 mg Cu+2 L–1 (2.14 mg CuSO4 5H2O L–1; 30% 96 h-LC50) for seven days and control individuals were divided into three groups: the first two were sensitized and non-sensitized with Micrococcus lysodeikticus, and the third was sensitized with heat-killed yeast. Lysozyme activity was tested in the first two groups and phagocyto...

Se evaluó las respuestas inmunológicas y de sistemas enzimáticos antioxidantes que participan en el control de toxicidad de oxidoradicales en la ostra perla Pinctada imbricata, después de la exposición aguda (7d) a 25 y 100% de la fracción soluble de Fuel Oil Nº6 (FSA), una fuente de hidrocarburos poliaromáticos y de metales pesados en ecosistemas...

The immune and antioxidant enzyme defenses in pearl oyster Pinctada imbricata were evaluated after shot-term (7d) exposure to 25 and 100% water-soluble fraction (WSF) of Fuel Oil N°6, a source of polyaromatic hydrocarbon and heavy metal contamination of marine ecosystems. Lysozyme activity in the digestive gland and the phagocytic activity of hemoc...