Chhorn Lim, H. Ako, C. L. Brown, K. Hahn-1997
Aquaculture, 151: 143-153
Abstract:
A study was conducted to evaluate the effects of feeding various
sources of dietary lipid on weight gain, feed conversion, survival and
fatty acid composition of juvenile Penaeus vannamei. Seven
semi-purified diets (35% protein and 3400 kcal of metabolizable
energy/kg) containing , defatted, freeze-dried shrimp meal, 1.0%
soybean lecithin and 0.5% cholesterol were supplemented with 6.5%
of either stearic acid, coconut, safflower, corn, soybean, linseed or
menhaden fish oils. Each diet was fed to shrimp (1.00 +/- 0.03 g
average weight) in four replicate aquaria four times daily for 10
weeks. Weight gain, feed conversion and survival were best for
shrimp fed the diet containing menhaden fish oil. Shrimp fed the
linseed oil diet had the second highest weight gain, followed by
shrimp on soybean oil, corn oil, stearic acid, coconut oil and
safflower oil diets, respectively. Feed conversion values were a
reflection of weight gain. Results of this study show that both n-6 and
n-3 fatty acids are dietary essential for juvenile Penaeus vannamei,
although n-3 fatty acids promoted faster growth than n-6. However,
highly unsaturated fatty acids (HUFA) (20:5n-3 and 22:6n-3) had
better growth-promoting effect than 18:3n-3, due probably to the
limited ability of shrimp to bioconvert fatty acids to polyenoic forms
of longer chain length. The fatty acid composition of the shrimp
generally reflected that of the dietary lipids, especially for the diets
containing unsaturated fatty acids. Shrimp fed stearic acid and
coconut oil diets low in polyunsaturated fatty acids accumulated high
levels of 16:1 n-7 and 18:1 n-9.
(Tropical Aquaculture Research Unit, USDA-ARS-PWA, Hawaii
Institute of Marine Biology, P.O. Box 1346, Kaneohe, Hl 96744,
USA)
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