Optimization of a research diet for the Pacific white shrimp, Litopenaeus vannamei, using mixture model methodology

Two five-week growth trials were conducted using mixture methodology to optimize a reference diet for Pacific white shrimp, Litopenaeus vannamei, (0.47 g and 0.41 g initial weight in Trial 1 and Trial 2, respectively) using krill meal (Trial 1 only), menhaden fishmeal, squid meal, and soy protein isolate (SPI). In Trial 1, the combination of ingredients yielding the highest final weight was fish:squid:SPI:krill 34.1:44.9:20.2:0.8. Because of its relative ineffectiveness, krill meal was removed in Trial 2. The optimum combination of ingredients was fish:squid:SPI 0.0:80.6:19.4%. Increasing SPI beyond 20% relative inclusion rapidly reduced final weight. Both trials indicated that a blend of marine ingredients and SPI base mixes at a ratio of approximately 4:1 optimized the final weight of the shrimp. In Trial 2, fishmeal was found to be marginally lower in nutritional quality than that of squid meal. These results indicate that mixture methodology is effective in optimizing diets for shrimp.