Nutritional
evaluation of fatty acids for the open thelycum shrimp, Litopenaeus
vannamei: I. Effect of dietary linoleic and linolenic acids at different
concentrations and ratios on juvenile shrimp growth, survival and fatty acid
composition
M.L. González-Félix, A.L. Lawrence, D.M.
Gatlin III, M. Perez-Velazquez-2003
Aquaculture
Nutrition, 9(2): 105
Abstract:
A 6-week feeding trial was conducted to
evaluate the nutritional value of dietary linoleic (18:2n-6, LOA) and
linolenic (18:3n-3, LNA) acids for juvenile Litopenaeus vannamei by
determining their effects on growth, survival and fatty acid composition of
hepatopancreas and muscle tissue. Diets were formulated to contain 5% total
lipid. A basal diet contained only palmitic and stearic acids, each at 2.5%
of diet. Six diets contained one of three levels (0.25, 0.5 and 1%) of
either LOA or LNA, and three diets had different ratios of LNA/LOA (1, 3, 9)
at a combined inclusion level of 0.5% of diet. An additional diet contained
0.5% of a mixture of n-3 highly unsaturated fatty acids (HUFA). The fatty
acid profile of hepatopancreas and muscle of shrimp reflected the profile of
the diets. HUFA of the n-3 family showed higher nutritional value than LOA
or LNA for juvenile L. vannamei by producing significantly (P < 0.05)
higher final weight and weight gain. Neither LOA nor LNA, alone or in
combination, improved growth significantly compared with shrimp fed the
basal diet. Thus, dietary requirements for LOA and LNA were not demonstrated
under these experimental conditions.
(TAES Shrimp Mariculture Project, Texas A & M University System, Port
Aransas, TX, USA)