ENGINEERING SENIOR DESIGN COURSE FOR DEVELOPMENT OF A NOVEL AUTOMATED LIVE FEED SYSTEM FOR LARVAL FINFISH
This project focused on developing an automated feeder for live Artemia, by way of an integrated engineering Senior Design course. Team members came from Electrical, Computer, Mechanical, Biological and Agricultural Engineering as well as Biology and Nutrition. Hydrodynamics (i.e. interactions of fluid motion and solid bodies) affect oyster aquaculture within every phase of culture. It is also a factor that is not well understood and yet has many direct and indirect implications on the success of any particular oyster aquaculture endeavor. As the industry continues to grow, it is imperative that the influence of hydrodynamics on oyster aquaculture is thoroughly understood.
Proper siting and management of aquaculture emplacements require a comprehensive understanding of the hydrodynamics involved and its impact on the cultured oysters. Unfortunately, literature is conflicting on the influence of hydrodynamics in regard to oyster feeding and growth. Feeding and growth limiting velocities are reported that range from 1 to above 22 cm s1. This is in contrast to thriving oyster reefs in a natural setting that exist and thrive above 15 cm s-1.
Upweller aquaculture systems are particularly influenced by flow that regulates food, oxygen, and water quality within the bed of oysters being cultured. Upweller systems have reported superficial velocities that range from 0.5 to 7.1 cm s-1. In practice, higher current velocities are desirable because they increase delivery of food to the oysters, improve water quality, and enhance dispersal of biodeposits. Upweller systems consist of a culture unit with a screened bottom that supports a bed of oysters, which approximates porous media in a packed bed reactor. This allows the application of packed bed reactor theory to upflow aquaculture systems.
A series of experiments were conducted using upflow tubes constructed from 2-inch (5 cm) polycarbonate tubes packed with juvenile oysters (1-2 cm) that were subjected to 6 superficial velocities (0.5, 1, 2, 4, 8, 16 cm s-1). The upflow tubes were designed to create a predictable and repeatable flow within a porous packed bed of solid material. The tubes had sampling ports along the porous bed zone which double as ports for measurement (i.e. differential pressure). The results from the physical and physical-biological experiments were used to calibrate axial dispersion models developed from packed bed reactor theory. The development of the axial dispersion parameters will allow for the design and optimization of upweller aquaculture systems. This presentation summarizes the findings of previous studies, details experiment methodology, model development and calibration, and provides results of hydrodynamic effects on growth and feeding of juvenile oysters within a packed bed. Early life stage development is a critical time for culture of finfish. For many species, live feed such as Artemia or copepods may be required during this period, and, due to the high metabolism, feedings every few hours are required. As a result, this time period is a critical and highly labor intensive period. In this study, a live feed pumping system was developed to pump multiple different types of Artemia to customize feed for different treatment types.
Among critical aspects of the study were use of live feed (addressed in another paper); larval development of internal organs; and overall growth and health of animals fed different prebiotic and probiotic formulations. This presentation will focus primarily on the educational and pedagogical challenges and opportunities at the intersection of engineering and biology with specific focus on live feeds in larval aquaculture. Ongoing development of the system, as well as educational objectives and outcomes will be presented.
Keywords : Artemia, live feed, automation, education, engineering.
