Ecological theory as a management strategy of microbial community in microbial-based systems for culture of fish and shrimp

• Grant number: 19/17521-0
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Start date: October 18, 2019
• End date: February 17, 2020
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Aquaculture
• Principal Investigator: Rodrigo Schveitzer
• Grantee: Fabrini Copetti Temistocles de Oliveira Alves
• Supervisor: Olav Vadstein
• Host Institution: Instituto de Saúde e Sociedade (ISS). Universidade Federal de São Paulo (UNIFESP). Campus Baixada Santista. Santos , SP, Brazil
• Institution abroad: Norwegian University of Science and Technology (NTNU), Norway
• Associated to the scholarship: 17/24583-6 - Effect of different levels of bioflocs on bacterial diversity in intensive shrimp farming, BP.MS

Abstract

The use of microbial-based systems to culture aquatic organisms has increased in the last years. Inthese systems, e.g. Recirculation Aquaculture System (RAS) and the Biofloc Technology (BFT),stocking densities are high and water exchange is low. Water quality is controlled by microorganismsthat occur in great quantity and diversity. Although beneficial species are present in the system,pathogenic opportunistic organisms can also grow and interact with cultured organisms, negativelyimpacting the production. In order to control the pathogenic species, Norwegian researchers have beenused the ecological theory of r/K selection as a foundation to control pathogenic invasion. After 25years testing the use of this theory to manage RAS to the culture of marine fishes, they concluded thatmodifying the environment of culture to promote the selection of k-strategists species is an effectivestrategy of management. Although many advances have been obtained with the use of this theory inRAS, it is necessary to validate the use of this strategy in another microbial-base system, e.g. BFT.RAS and BFT are managed differently and it is necessary to consider that adjusts will be necessary inorder to apply the ecological concept in the BFT. In my master project, we are using the ecologicaltheory of r/k-selection to manipulate the microbial community and minimize the growing ofopportunistic pathogen organisms as Vibrios. The results obtained, by using metagenomics techniques,are the first to evaluate the ecological theory of selection in BFT. The amount of data to be analyzed arechallenging and in this sense, counting with the experience of the Prof. Olav Vadstein, which waspioneer in using ecological theories to manage microbial communities, will be very important in thedata analyses and manuscript writing. In addition to the activities related to my master project,participating of the laboratory activities will be very important to learn new technics (e.g. DGGE) thatwill be incorporate in our laboratory at the UNIFESP. (AU)