Feeding juvenile Artemia enriched with ascorbic
acid improves larval survival in the spiny lobster Jasus edwardsii
G.G.
Smith, M.R. Brown, A.J. Ritar-2004
Aquaculture Nutrition, 10(2): 105-112
Abstract:
Newly
hatched Jasus edwardsii phyllosoma were fed unenriched Artemia
[endogenous ascorbic acid (AA) concentration of 166 µg g-1
dry weight (dw)], Artemia supplemented with algae (AA concentration
594 µg g-1 dw) or with ascorbyl-2-polyphosphate
(A2P) (AA concentration 11 737 µg g-1 dw) to
examine possible benefits of AA enhancement on culture. Plain or
algal-enriched Artemia were fed continuously for 28 days in two
treatments during the study. Four other treatments received A2P-enriched Artemia
on a progressive basis starting from the commencement of the trial (D-0),
the third (D-3), sixth (D-6) or ninth day (D-9) of Stage I (14 days)
and similarly during Stage II (14 days). Prior to the commencement of
A2P supplementation, plain Artemia were supplied to these animals. By
Stage III (28 days feeding), algal, D-0 and D-3 phyllosoma had attained
the largest size. The uptake and retention of AA by Stage III phyllosoma
appeared to be dose-dependent with the highest concentration of AA
incorporation evident in D-0 phyllosoma (1816 µg g-1
dw), while algal and plain phyllosoma contained the lowest concentrations
(600 and 300 µg g-1 dw, respectively). Survival
at Stage III was highest in D-0 phyllosoma (89%) and lowest in plain
phyllosoma (51%). There was a positive relationship between phyllosoma AA
concentration and larval survival (R2 = 0.8328, P < 0.0001).
D-0 phyllosoma had the lowest stress index when subjected to an
osmotic/temperature activity test, indicative of better survival in culture
compared to plain, algal and D-9 phyllosoma, which had consistently higher
indices. A negative relationship existed between phyllosoma AA concentration
and stress indices at Stage III (R2 = 0.9263, P < 0.0001),
suggesting that AA from the Artemia diet conferred stress resistance.
(Marine
Research Laboratories, Tasmanian Aquaculture and Fisheries Institute,
University of Tasmania, Nubeena Crescent, Taroona, Tasmania 7053, Australia.
E-mail: ggsmith@utas.edu.au)