Effect of low
salinity on growth and survival of postlarvae and juvenile Litopenaeus
vannamei
S. Laramore, C.R. Laramore, J. Scarpa-2001
Journal of the World Aquaculture Society, 32(4):
385-392 (from Current Contents)
Abstract :
The effect of low salinity on survival and growth of
the Pacific white shrimp Litopenaeus vannamei was examined in the laboratory
due to the interest of raising shrimp inland at low salinities. In three
separate experiments, individual L. vannamei postlarvae (similar to 0.1 g)
were cultured at salinities of either 0.5, 1, 1.5, 2, or 3 ppt (N = 5 or
10/treatment) for 18 to 40 d at 30 C in individual 360-mL containers. In
each experiment controls of 0 and 30 ppt were run. There was no postlarval
survival at salinities < 2 ppt. Survival was significantly different (P
< 0.01) at 2 ppt (20%) compared to 30 ppt (80%). Growth was also
significantly different (P < 0.01) at 2 and 3 ppt compared to 30 ppt
(416%, 475%, and 670%, respectively). A fourth experiment compared juveniles
(similar to 8 g) and postlarvae (similar to 0.05 and 0.35 g). Shrimp were
cultured at salinities of 0, 2, 4, and 30 ppt for 40 d at 25 C, in
individual 360-mL and 6-L containers (N = 7/treatment). There was no
postlarval survival at < 2 ppt. Postlarval survival at 4 ppt (86%) was
not significantly different (P > 0.05) from 30 ppt (10090). Juveniles
exhibited better survival at lower salinities (10090 at 2 ppt) than 0.05 and
0.35 g postlarvae (2990 and 14% respectively, at 2 ppt). The effects of
salinity on growth varied with size/age. Final growth of 0.05 g postlarvae
at 2 ppt (69390) was significantly less (P < 0.01) than at 4 ppt (1085%)
and 30 ppt (106490). Growth of 0.35 g postlarvae was significantly less (P
< 0.01) for 4 ppt (175%) than for 30 ppt (264%). There was no growth data
for juveniles (8 g). It appears from these experiments that the culture of
L. vannamei poses risks when performed in salinities less than 2 ppt.
(Harbor Branch Oceanog Inst Inc, Aquaculture Div,
5600 US 1 N, Ft Pierce, FL 34946, USA)