Abstract
White sturgeon (Acipenser transmontanus) are a niche species within the aquaculture industry. Sturgeon are highly prized for caviar production which represents this industry’s largest source of income. Sturgeon are a long-lived species with maturity taking up to 10-15 years. Previous research efforts focused on yearling sturgeon and caviar producing females due to these being seen as high impact areas. However, nutritional guidelines for juvenile sturgeon in the grow out phase are not well documented or understood. This phase begins at year 1 and continues until year 3 or 5 when they can be sexed and sorted. This phase represent a significant cost investment for farmers as all fish must be kept on until sexing can occur, but only females are desired due to their ability to produce caviar later in life. The overarching goal of this dissertation is to determine the macronutrient requirements of sturgeon during the growout period, develop diets based on alternative ingredients that offer potentially lower costs with minimal degradation of growth performance. To approach this problem, we are utilizing a novel experimental design called mixture design to examine constraints in diet formulation and how they relate to growth performance and other desired metrics. Secondarily, we are validating the use of mixture design in white sturgeon, a lesser studied species, and in rainbow trou, a well-studied species. The results from this work agree with previous work carried out on white sturgeon near the grow out phase, but with the recommendation of higher protein and lower fat levels in the diets. Sturgeon appear to grow well on blends containing poultry, corn, and soy products with some antagonism towards growth in diets with higher levels of both corn and soy. The predicted diet blend formulation has a lower cost and FCR than the fishmeal control diets, indicating that commercial diets can be improved based on this research. The study performed with rainbow trout showed that even with lower inter-individual variation and an unfavorable diet design landscape the mixture design approach can still produce valid predicted blend formulations to enhance growth.