Recipient Organization
CHEYNEY UNIVERSITY OF PENNSYLVANIA
1837 UNIVERSITY CIRCLE, BOX 200
CHEYNEY,PA 19319
Performing Department
Aquaculture Research and Education Center
Non Technical Summary
The cost for feed can represent from 50-60% of the total rearing cost for fish reared in captivity. These rates can vary significantly depending upon the size of the fish, the temperature in the rearing environment, and the amount of energy in the feed. Historically, however, the rates at which fish are fed have been determined using subjective criteria that can lead to either underfeeding (resulting in reduced growth) or overfeeding (resulting in low feed efficiencies). Two previous studies in our laboratory have helped with the determination of a mathematical formula to accurately determine the amount of feed to be fed daily to juvenile rainbow trout which will take into account the three important factors listed above and will maximize growth while minimizing waste and have evaluated the comparative feeding efficiency and weight gains obtained with several other published feeding formulas for trout. The data from this second study, though variable, indicates that feeding formulas which take into account all three of the parameters above outperform those which only take into account one or two, but the results were highly variable and did not address the impact of different feed formulations. Three studies will be conducted to better explain the results we have seen in previous studies: AREC-09-01: Impact of Fish Density on the Calculated "F" Factor in the Smith Feeding Equation. This study will assess the differences in individual fish feeding behaviors and the impact of different fish densities on the amount of food consumed. The data from this study will allow for the determination of the impact of fish group dynamics and will begin to provide data on the impact of fish density on feeding rates AREC-09-02: Effect of Feed Processing Method on Weight Gain, Carcass Composition, and Digestible Energy Values for Rainbow Trout. Anecdotal information indicates that altering the processing methods for the same feed formulation may lead to distinct differences in fish performance. The objective of this study will be to determine if extrusion processing leads to an increase in the available calories for fish fed a specific formulation when contrasted with fish fed the same formulation pelleted with a more standard compression method. Two groups of fish will then be fed these formulae for twelve weeks to determine the impact on weight gain, feed efficiency, and carcass composition. AREC-09-03: Effect of Rearing Temperature on the Caculated "F" Factor in the Smith Feeding Equation. Fish feeding rates are directly related to the temperature of the water in which they are being reared. Though the Smith Feeding Equation does take temperature into account in its calculations, this study will further test this relationship and may allow for calculated feeding amounts to be adjusted even more precisely so as to provide the most efficient feeding rates which will minimize food waste and maximize growth.
Animal Health Component
30%
Research Effort Categories
Basic
50%
Applied
30%
Developmental
20%
Goals / Objectives
The first project will involve assessing the impact of fish rearing density on feeding formulae for rainbow trout with the aim of reducing the cost of growth for this species in intensive culture. The second study builds on previous anecdotal data from our laboratory which indicated that the processing method used to create the pelleted feed may have significant impacts on energy availability and on the weight gain and carcass composition of farmed fish. The last study will begin to refine the calculated impact of rearing temperature on the Smith Feeding Formula which we are attempting to validate in our laboratory. The overriding goal for all three of these projects is to improve the economic efficiency and profitability of aquafarming in Pennsylvania and throughout the region. Expected outputs for this grant will include at least two peer reviewed publications and one oral/poster presentation at a national/international conference.
Project Methods
This grant will provide support for three related projects: AREC-09-01: Impact of Fish Density on the Calculated "F" Factor in the Smith Feeding Equation. This study will assess the differences in individual fish feeding behaviors and the impact of different fish densities on the amount of food consumed. The data from this study will allow for the determination of the impact of fish group dynamics and will begin to provide data on the impact of fish density on feeding rates. AREC-09-02: Effect of Feed Processing Method on Weight Gain, Carcass Composition, and Digestible Energy Values for Rainbow Trout. Anecdotal information indicates that altering the processing methods for the same feed formulation may lead to distinct differences in fish performance. The objective of this study will be to determine if extrusion processing leads to an increase in the available calories for fish fed a specific formulation when contrasted with fish fed the same formulation pelleted with a more standard compression method. Two groups of fish will then be fed these formulae for twelve weeks to determine the impact on weight gain, feed efficiency, and carcass composition. AREC-09-03: Effect of Rearing Temperature on the Caculated "F" Factor in the Smith Feeding Equation. Fish feeding rates are directly related to the temperature of the water in which they are being reared. Though the Smith Feeding Equation does take temperature into account in its calculations, this study will further test this relationship and may allow for calculated feeding amounts to be adjusted even more precisely so as to provide the most efficient feeding rates which will minimize food waste and maximize growth.