RESUMO

The use of Beneficial Microorganisms for Corals (BMCs) to increase the resistance of corals to environmental stress has proven to be effective in laboratory trials. Because direct inoculation of BMCs in larger tanks or in the field can be challenging, a delivery mechanism is needed for efficient transmission of the BMC consortium. Packaged delivery mechanisms have been successfully used to transmit probiotics to other organisms, including humans, lobsters, and fish. Here, we tested a method for utilizing rotifers of the species Brachionus plicatilis for delivery of BMCs to corals of the species Pocillopora damicornis. Epifluorescence microscopy combined with a live/dead cell staining assay was used to evaluate the viability of the BMCs and monitor their in vivo uptake by the rotifers. The rotifers efficiently ingested BMCs, which accumulated in the digestive system and on the body surface after 10 min of interaction. Scanning electron microscopy confirmed the adherence of BMCs to the rotifer surfaces. BMC-enriched rotifers were actively ingested by P. damicornis corals, indicating that this is a promising technique for administering coral probiotics in situ. Studies to track the delivery of probiotics through carriers such as B. plicatilis, and the provision or establishment of beneficial traits in corals are the next proof-of-concept research priorities.

RESUMO

Objective. It was studied the respiration and ammoniacal excretion of zoeas and mysis of Litopenaeus vannamei fed with the diet used traditionally (of microalgae and nauplios of Artemia) and another alternative (not traditional) of microalgae with rotifers. Materials and methods. After four hours the oxygen consumption and ammonia excretion in BOD bottles with 60 larvae (closed respirometers) was estimated. The concentrations of O2 and NH4+ were measured with an electrode polarográfico in the first case and with the indophenol blue technique for the second. Results. In zoea, oxygen consumption increased with development and showed statistical differences (p=0.023). In mysis, the oxygen consumption were significance in the traditional diet, whereas no differences were alternative (p=0.003). In both stages for the ammoniacal excretion increased development stage and there were detected statistical difference (p<0.001), although to the diets were not noticed significant differences. Conclusions. A higher energy absorption for zoea (I, II y III) what mysis (I, II y III) larvae was obtained, this is likely an interaction between rates of respiration and excretion caused by variations in the efficiency of absorption by the larvae. The weights obtained in both larvae were not supplied with differences between diets.

Objetivo. Se analizó la respiración (O2) y excreción amoniacal (NH4+) en larvas zoea y mysis de camarón blanco Litopenaeus vannamei, alimentadas con las dietas tradicionales (microalgas y nauplios de Artemia) y no tradicionales (microalgas y rotíferos). Materiales y métodos. A las cuatro horas de experimentación se estimó el consumo de oxígeno y la excreción de amonio en botellas BOD con 60 larvas (respirómetros cerrados). La concentración de O2 se midió con un electrodo polarográfico y la NH4+ se determinó con la técnica de azul de Indofenol. Resultados. En zoea, el consumo de oxígeno incrementó con el desarrollo y se presentaron diferencias estadísticas (p=0.023). En mysis, los consumos de oxígeno presentaron una significancia entre la dieta tradicional, mientras en la alternativa no se obtuvieron diferencias (p=0.003). La excreción en ambos estadios larvales aumentó con la fase y se detectaron diferencias estadísticas (p<0.001), aunque no se registraron diferencias significativas en las larvas respecto a las dietas suministradas. Conclusiones. Se obtuvo una absorción de energía superior para las zoea (I, II y III) que mysis (I, II y III), esto probablemente a una interacción entre las tasas de respiración y de excreción provocada por variaciones en la eficiencia de absorción de las larvas. Los pesos obtenidos en ambas larvas no resultaron con diferencias entre las dietas suministradas.

Assuntos

RESUMO

En este trabajo se reportan las especies de Brachionidae reconocidos en las muestras recogidas en octubre de 2010 en la albufera Laguna El Paraiso, Huacho (11°13' − 11° 10'S, 77° 35' − 77°40'W). Cinco especies fueron determinadas: Keratella tropica, Brachionus quadridentatus, B. urceolaris, B. angularis y B. ibericus Ciros-Pérez 2001. Este último es un nuevo reporte para el Perú y amplía su distribución a nivel mundial

This paper reports the Brachionidae species recognized in samples collected in October 2010 in the albufera Laguna El Paraiso, Huacho (11°13 − 11°10'S , 77°35' − 77°40'W). Five species were determined: Keratella tropica, Brachionus quadridentatus, B. urceolaris, B. angularis and B. ibericus Ciros-Pérez 2001, which is a new report for Peru and this report expanding its worldwide distribution

RESUMO

Zooplankton may be regarded as a sensitive tool for monitoring environmental variations in coastal lagoons due to their ability to immediately react to changes in the water column trophic features and salinity levels. As a coastal lagoon with a broad history of anthropic influence, Rodrigo de Freitas Lagoon (Rio de Janeiro, Brazil) is widely used for water sports and artisanal fishing. The present study aimed to expand the knowledge base about zooplankton in the Rodrigo de Freitas Lagoon by assessing the composition and time-spatial distribution of the major zooplankton groups. Samples were collected fortnightly from at four distinct sampling points August 2001 to July 2002. At each point, salinity, temperature, dissolved oxygen and water transparency were measured. During the study period, the lagoon behaved as an spatially homogeneous environment in what regards the abiotic variables. However, all these variables showed significant differences along the time, mainly related to seasonality (air temperature and rainy and dry periods). The zooplankton community showed low taxonomic richness, with the predominance of species commonly found in coastal lagoons, especially with mesohaline conditions, as well as those found in estuaries. An interesting fact was the rise in zooplankton abundance at all sampling points right after a fish kill event. Such increase was caused mainly by the Brachionus plicatilis O.F. Müller 1786 species. Thus, the zooplankton community was affected by physical and chemical factors, mainly by the dissolved oxygen decline event and variations in the influx of seawater into the lagoon. In addition, phytoplankton availability and fish predation pressure were suggested as important regulating factors of the zooplankton community.

RESUMO

Zooplankton may be regarded as a sensitive tool for monitoring environmental variations in coastal lagoons due to their ability to immediately react to changes in the water column trophic features and salinity levels. As a coastal lagoon with a broad history of anthropic influence, Rodrigo de Freitas Lagoon (Rio de Janeiro, Brazil) is widely used for water sports and artisanal fishing. The present study aimed to expand the knowledge base about zooplankton in the Rodrigo de Freitas Lagoon by assessing the composition and time-spatial distribution of the major zooplankton groups. Samples were collected fortnightly from at four distinct sampling points August 2001 to July 2002. At each point, salinity, temperature, dissolved oxygen and water transparency were measured. During the study period, the lagoon behaved as an spatially homogeneous environment in what regards the abiotic variables. However, all these variables showed significant differences along the time, mainly related to seasonality (air temperature and rainy and dry periods). The zooplankton community showed low taxonomic richness, with the predominance of species commonly found in coastal lagoons, especially with mesohaline conditions, as well as those found in estuaries. An interesting fact was the rise in zooplankton abundance at all sampling points right after a fish kill event. Such increase was caused mainly by the Brachionus plicatilis O.F. Müller 1786 species. Thus, the zooplankton community was affected by physical and chemical factors, mainly by the dissolved oxygen decline event and variations in the influx of seawater into the lagoon. In addition, phytoplankton availability and fish predation pressure were suggested as important regulating factors of the zooplankton community.

RESUMO

Zooplankton may be regarded as a sensitive tool for monitoring environmental variations in coastal lagoons due to their ability to immediately react to changes in the water column trophic features and salinity levels. As a coastal lagoon with a broad history of anthropic influence, Rodrigo de Freitas Lagoon (Rio de Janeiro, Brazil) is widely used for water sports and artisanal fishing. The present study aimed to expand the knowledge base about zooplankton in the Rodrigo de Freitas Lagoon by assessing the composition and time-spatial distribution of the major zooplankton groups. Samples were collected fortnightly from at four distinct sampling points August 2001 to July 2002. At each point, salinity, temperature, dissolved oxygen and water transparency were measured. During the study period, the lagoon behaved as an spatially homogeneous environment in what regards the abiotic variables. However, all these variables showed significant differences along the time, mainly related to seasonality (air temperature and rainy and dry periods). The zooplankton community showed low taxonomic richness, with the predominance of species commonly found in coastal lagoons, especially with mesohaline conditions, as well as those found in estuaries. An interesting fact was the rise in zooplankton abundance at all sampling points right after a fish kill event. Such increase was caused mainly by the Brachionus plicatilis O.F. Müller 1786 species. Thus, the zooplankton community was affected by physical and chemical factors, mainly by the dissolved oxygen decline event and variations in the influx of seawater into the lagoon. In addition, phytoplankton availability and fish predation pressure were suggested as important regulating factors of the zooplankton community.