|The effects of soybean-based diets, with and without amino acid supplementation, on growth and biochemical composition of juvenile American lobster, Homarus americanus|
Floreto, E.A.T.; Bayer, R.C.; Brown, P.B. (2000). The effects of soybean-based diets, with and without amino acid supplementation, on growth and biochemical composition of juvenile American lobster, Homarus americanus. Aquaculture (189): 211-235
In: Aquaculture. Elsevier: Amsterdam; London; New York; Oxford; Tokyo. ISSN 0044-8486, more
|Authors|| || Top |
- Floreto, E.A.T.
- Bayer, R.C.
- Brown, P.B.
The feasibility of feeding soy-based diets for the pound culture of the American lobster was investigated in a factorial study using diets (40% protein) containing various proportions of extruded-expelled, low-fat soybean meal (SBM) (0%, 25%, 50%, 75%, 87.5% and 100% of dietary protein) and fish meal (FM), with and without amino acid supplementation (arginine, leucine, methionine and tryptophan), in a 60-day feeding trial using late Stage 5 juveniles. The supplemental amino acids were added at levels to simulate the essential amino acid (EAA) profile of juvenile lobsters. The 0% SBM diet approximated salted fish and fish racks, the industry diet for pounded lobsters. A diet of fresh blue mussel, a component of the lobster's natural diet, was included for comparison. Supplementation and SBM levels of not more than 50% of dietary protein significantly resulted in higher body weight gains (BWGs) than diets without supplementation or with higher SBM levels. Survival was not significantly different for juveniles fed the supplemented diets and the non-supplemented diets containing FM. Juveniles fed the non-supplemented 100% SBM diet suffered early mortality. Supplementation significantly shortened molting cycles and was crucial for survival in juveniles fed the 100% SBM diet. Interactions between supplementation and level of dietary SBM on survival, BWG and duration of the molting cycle were significant. Growth performance of juveniles fed blue mussel were comparable to those of juveniles fed the supplemented 50% SBM diet. The levels (% of protein) of arginine, phenylalanine and tryptophan were significantly higher in juveniles fed the supplemented diets, while tyrosine, aspartate, glutamate and serine were significantly higher in juveniles fed the non-supplemented diets. Arginine levels in juveniles fed the supplemented diets were nearly twice those of juveniles fed the non-supplemented diets. Interactions between SBM level and supplementation on lobster amino acid profile were not significant. Supplementation and decreasing levels of dietary SBM (lower content of 18:2n-6, the major polyunsaturated fatty acid (PUFA) in SBM) were associated with better growth and resulted in increasing proportions (% of total) of 20:5n-3, 22:6n-3 and n-3/n-6 PUFA ratios in juvenile carcass. Based on weight gain, replacement of fish protein with SBM in practical diets at no more than 50% of dietary protein appears feasible, with multiple amino acid supplementation significantly enhancing growth performance.