Effect of Dietary Protein Sources on Growth and Body Composition of Snail, Semisulcospira gottschei

Abstract

A feeding experiment was conducted to determine a dietary protein source for juvenile snail, Semisulcospira gottschei. Eight experimental diets (designated as 1–8) were formulated to contain 31% casein, 42% fish meal, 31% blood meal, 39% meat meal, 46% corn gluten meal, 57% soybean meal, 50% cottonseed meal with 23% casein, and 50% wheat flour with 6% casein, respectively, as dietary sole protein sources. Snails (37 ± 3.4 mg/snail) were randomly distributed into 25 L aquaria (20 L water each) in a recirculating aquarium system at a density of 100 juveniles per aquarium. Three replicate groups of snails were fed one of the experimental diets ad libitum once in every 2 d for 12 wk. At the end of the feeding experiment, survival of snails ranged from 77 to 89%, and was not significantly different among the treatments. Snails fed Diet 7 containing 25.3% crude protein deriving from cottonseed meal and casein grew faster than did snails fed other diets, except for snails fed Diet 6 containing soybean meal as a protein source. Growth of snails fed diets containing blood meal, corn gluten meal, and meat meal was the least of snails fed any diet. Crude protein, crude lipid, and ash contents of whole body varied remarkably with dietary protein source. The present findings suggest that dietary protein source could affect the body weight and proximate composition of snails. Cottonseed meal and soybean meal might be a more preferable dietary protein source for snail juvenile compared with other ingredients tested.