Deste percentual, 4,9% assentaram em coletores plásticos e 43,93% em pó de concha. No primeiro experimento, recuperaram-se 48,83% de sementes em relação às larvas D utilizadas. Foi realizada a quantificação das larvas assentadas nos coletores plásticos e a taxa de recuperação e integridade das sementes após o destacamento. No primeiro experimento, testaram-se coletores de plástico arranhado consorciado com pó de concha em um tanque de assentamento, enquanto que no segundo foram utilizados dois tanques de assentamento, um contendo os coletores de plástico consorciado com pó de concha e apenas pó de concha, e, no outro tanque, utilizou-se epinefrina como estimulador da metamorfose. Foram realizados dois experimentos, o primeiro entre fevereiro e abril de 2008, e o segundo entre novembro e dezembro de 2008 no Laboratório de Moluscos Marinhos da Universidade Federal de Santa Catarina. O material foi escolhido devido à boa maleabilidade, o que facilita o destacamento das sementes. Foram utilizados coletores plásticos de polipropileno, presos a armações de bambu. O presente estudo teve como objetivo avaliar a taxa de assentamento larval e recuperação de sementes de ostras da espécie Crassostrea brasiliana, em laboratório, através do uso de coletores plásticos, epinefrina (C9H13NO3 C4H6O6) e pó de concha em tanques de assentamento. Settlement larvae Crassostrea brasiliana collectors spats Thus, the use of the collector plus shell powder resulted in a greater spat recovery when compared to the other treatments. The second experiment revealed 55.78% regarding the settled spats in comparison with the total of larvae used (using epinephrine), 78.62% in the treatment with the collector plus shell powder and 58.33% in the treatment only with shell powder. From this percentage, 4.9% settled in the plastic collectors and 43.93% in shell powder. The first experiment has shown a recovery rate of 48.83% of the spats in comparison with the D larvae used. The quantification was carried out of the larvae settled in the plastic collectors, and of the recovery and integrity of the spats after their detachment. In the first experiment, the scratched plastic collectors were tested consorting them with shell powder on the second, the plastic collectors were tested consorted with shell powder, only shell powder and epinephrine as the metamorphosis stimulator. Two experiments were carried out the first between February and April 2008, and the second between November and December 2008 at the Marine Mussel Laboratory of Santa Catarina Federal University (Laboratório de Moluscos Marinhos da Universidade Federal de Santa Catarina). The material was chosen due to its pliability - that favours the spat detachment. Polypropylene was used attached to bamboo frames. All Rights Reserved.This study aimed at the assessment, in the laboratory, of the larval settlement and spat recovery rates of oysters of the species Crassostrea brasiliana using plastic collectors, epinephrine (C9H13NO3 C4H6O6) and shell powder in settlement tanks. During this period, the water temperature was below 16☌.Ĭopyright © 2014, American Society for Microbiology. An initial increment in the number of PCR-positive oysters was reported at both field sites during the survey in the absence of significant mortality. Mass mortality was observed among oysters a few days after increases in the number of PCR-positive oysters and viral-DNA amounts were recorded. This difference may be related to earlier increases in water temperature. Although similar massive mortality rates were reported at the 4 sites, mortality was detected earlier in the pond and in the nursery than at both field sites. Mortality rates were recorded based on regular observation, and samples were collected to search for and quantify OsHV-1 DNA by real-time PCR. For this purpose, a single batch of Pacific oyster spat was deployed in 4 different locations in the Marennes-Oleron area (France): an oyster pond ("claire"), a shellfish nursery, and two locations in the field. Additional data are necessary to better describe mortality events in relation to environmental-parameter fluctuations and OsHV-1 detection. gigas in Europe have been related to the detection of a variant of OsHV-1 called μVar. Since 2008, mass mortality outbreaks among C. This virus has been classified as Ostreid herpesvirus 1 (OsHV-1) within the family Malacoherpesviridae. A particular herpesvirus was purified from naturally infected larval Pacific oysters, and its genome was completely sequenced. A number of bivalve species worldwide, including the Pacific oyster, Crassostrea gigas, have been affected by mass mortality events associated with herpesviruses, resulting in significant losses.
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