Zhi Yong Ju

Use of Fish Hydrolysates and Fish Meal Byproducts of the Alaskan Fishing Industry in Diets for Pacific White Shrimp Litopenaeus vannamei

Abstract We determined the suitability of four fish hydrolysates and two fish meals (Pacific halibut Hippoglossus stenolepus and arrowtooth flounder Atheresthes stomias; all derived from byproducts of the Alaskan fishing industry) as replacements for menhaden fish meal in shrimp diets. A control diet (30% crude protein; 8.5% crude lipid) was produced with menhaden meal (13% of diet). Experimental diets were manufactured by using each hydrolysate or fish meal to replace 50% of the menhaden meal on an isonitrogenous basis. Each diet was fed to Pacific white shrimp Litopenaeus vannamei in an outdoor, zero-water-exchange system for 8 weeks. Final weight, survival, feed efficiency, and growth rate were compared among treatments by analysis of variance. The final weights and growth of Pacific white shrimp fed two of the hydrolysates (one acidified to pH 3.8 and left in a liquid state; the other acidified, then neutralized to pH 6.5 and drum-dried) and the two fish meals were not different from those of shrimp f...

Classification and Quantification of Phospholipids and Dietary Effects on Lipid Composition in Pacific White Shrimp Litopenaeus vannamei

Abstract The phospholipid (PL) composition of Pacific white shrimp Litopenaeus vannamei and the diets on which they were reared during an 8-week indoor feeding trial was characterized. Nine PL classes, including phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidic acid, and phosphatidylserine, were detected and quantified in shrimp, diets, and feed ingredients by high-performance liquid chromatography. Total PL comprised the majority of total lipid—over 69.5% in shrimp tail muscle and over 60.1% in the shrimp whole body. The PC, PE, and PI classes were the most abundant, comprising over 40, 35, and 15%, respectively, of the PL in shrimp tails. Cardiolipin and ceramides were also detected in the shrimp whole body. Dietary crude protein content (40% versus 35%) significantly affected the PL composition of the shrimp whole body. Addition of shrimp floc (suspended particles from shrimp culture) to a 40% crude protein diet yielded higher Pacific white shrimp growth a...