Meeting Abstract
Aquaculture feeds, especially those for marine shrimp, utilize a major proportion of the global production of fish meal. Plant proteins are readily available, economical, and sustainable potential alternatives to fish meal. However, feeds containing high levels of plant proteins without marine protein have reduced attractability and palatability. The goal of our study was to identify chemical mixtures that increase the attractability and palatability of feed, substituting for fish meal. Our approach uses information about mechanisms of chemosensory processing and discrimination in marine crustaceans. We formulated a series of feed attractant mixtures (FAM) of varied composition, complexity, and cost, and we tested their efficacy in two laboratory assays, using krill meal as a comparator, on Pacific white shrimp, Litopenaeus vannamei. An attractability assay measured if shrimp moved toward, probed, and grabbed the release site of FAM. A palatability assay tested the ability of FAM, when incorporated into feed pellets, to increase ingestion. We found that FAM was highly attractive to shrimp, and that aqueous extracts of pellets containing FAM could be as attractive as pellets containing krill meal. FAM increased the amount of feed ingested above control levels and was sometimes as effective as krill meal; the increase varied with the amount and/or type of animal protein in the pellets. Our results demonstrate that chemical mixtures can be highly attractive to shrimp, and when incorporated into high-soy pellets, can increase feed palatability. Future directions include developing formulations with optimal efficacy:cost ratios and validating these results in grow-out experiments. Supported by Soy Aquaculture Alliance/United Soybean Board.
