Stanislaus Sonnenholzner

• Ph.D.
• Docente Investigador at Escuela Superior Politecnica del Litoral

Acute Hepatopancreatic Necrosis Disease (AHPND), caused by various species of Vibrio, results in significant mortality rates in global penaeid shrimp aquaculture. While antibiotics are commonly employed to combat this disease, concerns about the rapid emergence of resistant strains and their potential adverse effects on human health and the environ...

Penaeus vannamei is the main species of shrimp farmed worldwide, and for Ecuador it is the first non-oil economic sector. However, various pathogens, including white spot syndrome virus (WSSV), threaten the sustainability of shrimp farming. P. vannamei larvae are susceptible to WSSV infection via vertical or horizontal transmission. To decrease...

The bacterial community of the intestinal microbiota influences many host functions, and similar effects have been recently reported for the fungal community (mycobiota). Cobia is a tropical fish that has been studied for its potential in marine aquaculture. However, the study of its bacterial community has been underreported and the mycobiota has...

The median lethal concentration (LC 50 ) of unionized ammonia (NH 3 ‐N) in longfin yellowtail, Seriola rivoliana juveniles was assessed after 96 h of exposure using a semistatic water system. Experimental fish were exposed in triplicate to different ammonia concentrations: 0.55 ± 0.00; 0.94 ± 0.02; 1.18 ± 0.00; 1.72 ± 0.02, and 1.97 ± 0.09 NH 3 ‐N...

Some yeast strains have been proposed as probiotics to improve the health of cultured fish. Cobia is a tropical benthopelagic fish species with potential for marine aquaculture; however, one of the main limitations to its large-scale production is the high mortality of fish larvae. In this study, we evaluated the probiotic potential of autochthonou...

The biochemical nature and composition of fatty acids (FA's) in microalgae influence the nutritional quality and efficiency of this food source in bivalve larviculture. This research analyses the effect FA's content of Chaetoceros gracilis and Tisochrysis lutea on the FA's composition, growth and survival of Striostrea prismatica larvae. We analyse...

Pathogenic vibrios of farmed shrimp have acquired resistance to antibiotics commonly used in aquaculture, leading to a constant search for new, effective products to control them. In vitro methods currently used to evaluate possible solutions are expensive, tedious, and time-consuming. In contrast, the methyl thiazole tetra�zolium (MTT) reduction...

Hypoxia is a common concern in shrimp aquaculture, affecting growth and survival. Although recent studies have revealed important insights into hypoxia in shrimp and crustaceans, knowledge gaps remain regarding this stressor at the molecular level. In the present study, a gas chromatography–mass spectrometry (GC–MS)-based metabolomics approach was...

Some genera of bivalve molluscs have an iconic ancestral history that predominates in the culture of a civilization through time. The Pacific thorny oyster Spondylus crassisquama is a living example of this. This study presents the description of the early life cycle until obtaining juveniles; and, for the latter, different types of substrates were...

Its an error

The interest in developing a more diverse mollusk aquaculture in the tropical eastern Pacific has increased in recent years. In this region, the rock oyster Striostrea prismatica is being extracted and consumed massively. The species lives attached to large rocks, which offer firmness and stability in their high-energy environment. For aquacultural...

The use of probiotics, prebiotics and dietary fiber has become a common practice in shrimp aquaculture as alternatives to antibiotic treatment. However, not much is known about the metabolic mechanisms underlying the effects of probiotics and immunostimulant used in shrimp aquaculture. In this study, a gas chromatography−mass spectrometry (GC−MS) b...

The vibrios carrying the pirA and pirB toxin genes cause acute hepatopancreatic necrosis disease (AHPND) in cultivated shrimp, significantly affecting the yield. The use of probiotic strains is a promising strategy to prevent vibriosis in shrimp cultures. The microbial consortium formulated with three strains, Vibrio diabolicus (Ili strain), Vibrio...

Natural populations of the edible mangrove cockle (Anadara tuberculosa) are threatened by overexploitation and environmental degradation due to anthropogenic activities. The indoor production of larvae and early spat of mangrove cockles requires knowledge regarding the evolutionary characteristics of their larval morphology, associated with the app...

Outbreaks of white spot syndrome virus (WSSV) have caused serious damage to penaeid shrimp aquaculture worldwide. Despite great efforts to characterize the virus, the conditions that lead to infection and the infection mechanisms, there is still a lack of understanding regarding these complex virus-host interactions, which is needed to develop cons...

Vibrio parahaemolyticus is a causative agent of the acute hepatopancreatic necrosis disease (AHPND) that leads to massive mortalities in penaeid shrimp aquaculture worldwide. Mitigation of the significant economic losses caused by AHPND are hampered by knowledge gaps in the pathogenic mechanism of V. parahaemolyticus infection in shrimp. To provide...

Monoalgal and bialgal diet were tried in 2 stages of larval development of Striostrea prismatica: phase I from mixotrofic to early umbonated veliger larva and phase II until eyespot larvae. The monoalgal diets in phase I were Tisochrysis lutea, Pavlova lutheri and Nannochloropsis sp. In phase II, Tetraselmis suecica, T. chuii, Chaetoceros gracilis...

The emergence of new virulent Vibrio strains resistant to common antibiotics has caused significant economic losses to shrimp farming worldwide. It is mandatory to adopt new strategies to control shrimp farming related vibriosis. Essential oils (EOs) have several biological properties among of which the quorum sensing (QS) inhibitory activity is ap...

La ostra del Pacífico Crassostrea gigas es uno de los moluscos con mayor producción a escala global y el éxito de su cultivo depende principalmente de la producción de semillas bajo condiciones controladas, siendo la calidad del agua utilizada un factor preponderante. Se evaluó la producción de postlarvas, tanto en el desarrollo larvario como en et...

The bivalve Nodipecten subnodosus is one of the largest scallop species and has been selected as an appropriate species for mariculture, adapting the culture technology for production in equatorial waters of the eastern Pacific Ocean. A study of its larval development was performed, comparing standard technology with different treatments in terms o...

El cultivo de camarón es una de las principales actividades acuícola a nivel mundial, y para Ecuador representa el primer producto de exportación no petrolero. A pesar de su crecimiento expansivo, la industria camaronera es frecuentemente amenazada por brotes de enfermedades. Recientemente, varios vibrios han sido asociados a la enfermedad de necro...

White spot syndrome virus (WSSV) is one of the most virulent pathogens of cultured penaeid shrimp. Several control strategies are used commonly to mitigate the economic losses caused by the pathogen, such as application of antiviral products at farm level. One of the most practical method for the screening of potential anti-WSSV products is through...

In the search for probiotic bacteria from marine environments to control pathogenic Vibrio of cultivable marine species, this study focused on members of the genus Pseudovibrio. Based on its symbiotic features and antibacterial capacity, the genus Pseudovibrio could be used as probiotic to control vibriosis in shrimp culture. Fortythree isolates of...

The effects of mono- and bi-microalgal diets on shell length, organic tissue, and survival of Spondylus limbatus juveniles were tested in two separate feeding experiments. The first examined nine single species of microalgae: Chaetoceros gracilis, C. muelleri, Isochrysis aff. galbana (T-ISO), Tetraselmis chuii, T. maculata, Pavlova lutheri, Dunalie...

Antibiotics have been used massively for aquatic organism production. However, their use should be limited given the problems of increased antibiotic resistance, and new alternatives should be attempted, such as the use of plants extracts with antibacterial properties. The effect of the essential oil of oregano (Origanum vulgare) compared with thre...

The marine biodiversity program of CENAIM-ESPOL focuses on sessile invertebrates from the “‘El Pelado’ marine reserve”. The present study aims at understanding the different hierarchical levels of biodiversity found at the “El Pelado” and to guide biodiscovery initiatives. Generated biodiversity data were systematized in a database (Darwin Core sta...

This study investigated the effect of intermittent feeding on the water quality, occurrence of skin parasites, feed consumption, and growth performance of juveniles (102.7 ± 5.1 g) longfin yellowtail, Seriola rivoliana. Fish were exposed for 89 days to six different feeding regimes: continuous daily feeding fed one or twice a day (treatment 24R1 an...

The Pacific or Japanese oyster, Crassostrea gigas, was introduced into Ecuador in 1990; however, little is known about its cultivation in the Eastern Tropical Pacific. This study analyzes growth and the influence of environmental factors on two cohorts of C. gigas held in pearl nets suspended from a long line, in Ayangue Bay, Santa Elena Province,...

The rock oyster Striostrea prismatica is one of the most abundant species in the rocky coastal ecosystems of the tropical and subtropical eastern Pacific; however, natural banks are overexploited or depleted, so production by culture is recommended. Adult S. prismatica obtained from natural banks were conditioned for gonad maturation and spawning....

The growth, survival and influence of environmental factors were analysed in two cohorts of cultured Pteria sterna in Ayangue Bay, Province of Santa Elena, Ecuador (tropical Eastern Pacific). Juveniles representing cohorts I and II (8.4 ± 0.54 and 5.0 ± 0.17 mm in dorso-ventral axis) were deployed in November 2015 and February 2016, and grown in pe...

Treatment of upflow anaerobic sludge blanket (UASB) effluent from a paper mill in aerated activated sludge reactors involves high aeration costs. Moreover, this calcium-rich effluent leads to problematic scale formation. Therefore, a novel strategy for the aerobic treatment of paper mill UASB effluent in microalgal bacterial floc sequencing batch r...

Members of the bivalve molluscan family Spondylidae were very important elements in the world view of pre- Hispanic cultures of America, and today remain as symbols of culture heritage in contemporary society. In recent decades, given the importance they have for crafts and jewelry, as well as for fisheries and gastronomy, their exploitation has ca...

To replace costly mechanical aeration by photosynthetical aeration, upflow anaerobic sludge blanket (UASB) effluent of food-industry was treated in an outdoor MaB-floc raceway pond. Photosynthetic aeration was sufficient for nitrification, but the raceway effluent quality was below current discharge limits, despite the high hydraulic retention time...

The reproductive cycle of the rock oyster Striostrea prismatica was determined at two fishing areas, General Villamil and Ayangue (located on the southern coast of Ecuador), between May 2012 and April 2013. Monthly sampling campaigns were performed at both locations. The tissues were histologically examined to determine gonadal index (GI), oocyte d...

An alternative larval shrimp feeding regime, in which umbrella-stage Artemia were constituting the first zooplankton source was evaluated in the culture of Litopenaeus vannamei. In a preliminary experiment, umbrella-stage Artemia were fed to larvae from zoea 2 (Z2) to mysis 2 (M2) stages to identify the larval stage at which raptorial feeding start...

The tropical rock oyster Striostrea prismatica is a commercially valuable bivalve mollusc found along the Pacific tropical coast. A laboratory study was conducted to investigate broodstock acclimation at two temperatures (28.3 +/- 0.9 degrees C and 22.2 +/- 0.9 degrees C) fed a combined microalgae diet (Chaetoceros gracilis and Isochrysis galbana a...

The hypothesis that intraspecific competition affects survival and growth during the culture and harvest at extensive/semi-intensive Penaeus vannamei shrimp ponds was evaluated. Thus, the effect of stocking density on the biomass, shrimp average weight, survival, and economic performance during the culture (133 days) and at the harvest of the P. va...

The tolerance of Litopenaeus vannamei larvae to increasing concentrations of total ammonia nitrogen (TAN) using a short-term static renewal method at 26°C, 34 g L−1 salinity and pH 8.5 was assessed. The median lethal concentration (24 h LC50) for TAN in zoea (1-2-3), mysis (1-2-3) and postlarvae 1 were, respectively, 4.2-9.9-16.0; 19.0-17.3-17.5 an...

In recent years, some Ecuadorian shrimp farmers have reported several cases of muscle necrosis in P. vannamei grow out cultures, associated to low mortalities at harvest. This abnormal condition is characterized by focal to extensive necrotic areas in striated tail muscle tissues, displaying a white, opaque appearance. Furthermore, histological ana...

The main task of this research was to test certain health management strategies for cultured shrimp in order to improve overall production variables (yield, survival rate, weight and feed conversion ratio-FCR). To do so, four thorough studies were conducted with an emphasis on the use of three factors: the probiotic Vibrio alginolyticus (Ili strain...

The bivalve genus Spondylus, with its large and magnificent shells, has played an important cultural and economic role in coastal Ecuador that reaches back to Valdivian and Incan times. At least 2 of the 3 occurring species lately faced exploitation rates that the populations could not sustain, and a fishing ban for Spondylus calcifer and Spondylus...

Diseases are among the greatest threats affecting the sustainability of shrimp aquaculture. In Ecuador, diseases of cultured shrimp have been quickly transmitted from one region to another. Therefore, an early detection system of impending epidemics could serve as an important management tool for the aquaculture sector. We developed a system for th...

Experimentaciones en la Estación Experimental del CENAIM en Palmar El CENAIM concluyó en enero del 2005 la construcción de 38 estanques de 500 metros cuadrados cada uno para la experimentación con camarones (Litopenaeus vannamei), peces (Seriola rivoliana), y moluscos (Scallop y Ostras). Veinte de estos estanques tiene cubierta de invernadero, y do...

Supervivencias de Camarón Cultivado en el Ecuador antes de la Mancha Blanca La aparición del virus de la “Mancha Blanca” a mediados de 1999 ocasionó elevadas mortalidades (supervivencias < 20%) en los sistemas de cultivo de camarón.

Determinación de tasas de nitrificación en Biofiltros Los sistemas intensivos de acuacultura con reuso y recirculación del agua requieren de mecanismos físicos y biológicos para la remoción de los productos metabólicos originados por el ecosistema.

Ensayo de remoción de amonio por mineral zeolita: efecto del radio del soluto (amonio) con respecto al absorbente (zeolita) En el boletín informativo 107 reportamos la reducción de la capacidad de absorción (intercambio catiónico) del amonio por parte de un mineral de zeolita al incrementarse la salinidad del medio.

Ecuador Develops GIS Alert System for Shrimp Farming

Puede el bokashi alterar la calidad del suelgo, agua y camarón

EFECTO COMBINADO DE UNA PRECRIA EN HIPERTERMIA E INMUNOESTIMULACION. UNA ALTERNATIVA PARA INCREMENTAR LA PRODUCCION DE CULTIVOS SEMI-INTENSIVOS EN CONDICIONES DE WSSV En 1998, Ecuador alcanzó las máximas producciones de camarón de su historia 153,729 TM (CNA 1999) en una superficie de 175, 000 ha (CNA, 2000), es decir 1,923 lbs/ ha año (769 lbs/cic...

Efecto de la aplicación de material calcáreo sobre la calidad de agua y producción en estanques salinos de L.V. Los estanques de aquacultura deben ser encalados para corregir problemas de alcalinidad, dureza o acidez del agua y suelo basicamente. Para acuacultura se recomienda alcalinidades totales superiores a 20 mg/L (como CaCO3) para reducir la...

Comparación de la calidad de agua de los efluente de monocultivo y policultivos DB05 (mg/L) La sostenibilidad de la acuicultura ha sido cuestionada entre otras razones por los problemas que pueden causar la descarga de los efluentes de los estanques de cultivo en cuerpos de aguas naturales, debido a su carga de nutrientes, sólidos en suspensión, qu...

Balance de nitrógeno y fósforo en estanques de producción de camarón en Ecuador Balance de nitrógeno y fósforo en estanques de producción de camarón en Ecuador

Calidad de agua en un sistema de recirculación con biofiltros para la producción intensiva de postlarvas de camarón Litopenaeus vannamei La industria de la Acuicultura está enfrentando serios cambios técnicos con la finalidad de desarrollar formas económicas y efectivas de mejorar su producción. La producción de postlarvas de camarón Litopenaeus va...

Invernaderos: Seguimientos de Temperatura y Oxígeno Entre diciembre del 2001 y mayo del 2002 se realizaron dos series de experimentos para evaluar el efecto de las temperaturas altas en la supervivencia y el crecimiento del camarón utilizando invernaderos.

Resultados de la fase de engorde en invernaderos Continuando con la serie de experimentos que se están desarrollando en la estación experimental Pesglasa para evaluar el efecto del tratamiento térmico en la supervivencia del camarón, se realizó la fase de engorde en invernaderos.

WSSV y temperatura, inmunoestimulantes, vitaminas... ¿Cómo se relaciona todo? Los experimentos desarrollados a la fecha indican que a temperatura de 33°C disminuye tanto la prevalencia (porcentaje de animales positivos) como la intensidad de la infección en juveniles y en larvas (Boletín Septiembre 15).

Evaluación de materiales calcáreos utilizados en el cultivo de camarón en Ecuador Evaluación de materiales calcáreos utilizados en el cultivo de camarón en Ecuador

Chemical and physical analyses were conducted on bottom soil samples from 74 brackish-water ponds representing 40 shrimp farms in Ecuador. Most ponds had soils with pH > 6 and total carbon concentrations < 2.5%. Carbon was mostly in organic form, for the average concentration of carbonate carbon was 0.06%. The C: N ratio was 8 to 10 in soils with <...

— Total carbon concentration and respiration rate were greater in the upper 0.5-cm or 1.0-cm layers of pond soil than in deeper layers. The respiration rate expressed on either a dry soil weight basis or a soil carbon basis decreased with increasing soil depth. This suggests that the ratio of labile to refractory organic matter also declines with i...

Managing the accumulation of organic matter deposited on the bottom of shrimp ponds.. Do chemical and biological probiotics really work?

Ensayo de láminas plásticas para invernaderos en la Estación Experimental del CENAIM en Palmar: Transmisión de luz visible El uso de invernaderos para elevar la temperatura del agua y atenuar las infecciones por el virus de la “mancha blanca” en cultivos de camarón Litopenaeus vannamei fue implementado por la Fundación Centro Nacional de Acuacultur...

Ensayo de abosorción de amonio disuelto en agua por un mineral zeolita a diferentes salinidades Las zeolitas pertenecen a un gran grupo de silicatos hidratados constituídos por estructuras de aluminiosilicato y presencia de Na y Ca. A diferencia de los feldespatos que también estan constituídos por estructuras tetrahedricas de AlO4 y SiO4, las estr...

Carga de nutrientes en efluentes durante la cosecha de camarón cultivado en sistemas mono y policultivo con tilapia La liberación directa de efluentes de acuacultura hacia cauces de agua naturales genera continuamente la atención del público y de entidades gubernamentales y no-gubernamentales por el impacto que estos efluentes pueden tener sobre el...

Tolerancia de Temperatura La especie Litopenaeus (Penaeus) vannamei es un camarón tropical cultivado mundialmente en un amplio rango de temperaturas del agua (18º – 33ºC), sin embargo el valor óptimo descrito por varios autores para su cultivo se encuentra entre 28º a 31ºC.

Desafío con WSSV bajo fluctuaciones de temperatura En trabajos anteriores sobre el efecto de la temperatura del agua sobre la supervivencia del camarón infectado con el virus de la Mancha Blanca, se demostró que una temperatura constante de 33ºC por 8 días genera una respuesta inmune en el camarón correlacionada a una supervivencia superior al 90%,...

Pruebas de campo de varias estratégias de manejo para incrementar la producción camaronera Los experimentos de laboratorio muestran que a 33°C el virus de la Mancha Blanca no afecta la supervivencia del camarón.

Bioensayos de desafío al virus "Mancha Blanca" en camarones juveniles Penaeus vannamei bajo diferentes temperaturas del agua Desde la aparición del virus "Mancha Blanca" en el Ecuador hace dos años, el sector productor de camarón ha ensayado varias metodologías técnicas y no técnicas para controlar o disminuir las mortalidades del camarón en los es...

CULTIVO DE CAMARÓN: EXPERIENCIAS Y DESAFIOS EN EL USO DE INVERNADEROS Los estudios realizados por el CENAIM durante el año 2001, demostraron que con temperaturas del agua de 33°C el virus de la Mancha Blanca no provoca la muerte del Litopenaeus vannamei.

Cultivos experimentales de camarón en invernaderos Cultivos experimentales de camarón en invernaderos

El uso de los invernaderos como una alternativa de producción camaronera en Ecuador El uso de los invernaderos como una alternativa de producción camaronera en Ecuador

Supervivencia y respuesta inmune de camarones juveniles LV desafiados por via oral a WSSV a diferentes temperaturas

CENAIM Study examines effects of Transport on Shrimp Postlarvae Survival

Experiencias y desafíos en el uso de invernaderos

Greenhouse systems promising technique against WSSV in Ecuador

Chemical and Physical Properties of Shrimp Pond Bottom Soils in Ecuador