effect of salinity and temperature on oxygen consumption in
juvenile pink shrimp, farfantepenaeus paulensis
W. Wasielesky Jr., R.L. Santos,
C.S. Castano, A. Bianchini
Abstract:
A number of studies have been
carried out on the effects of salinity and temperature on different aspects
of physiology of cultured shrimps, which are important to the understanding
of oxygen requirements during variations of such factors. Juveniles
Farfantepenaeus paulensis (5.11 +/- 1.34 g) were pre-acclimated during 15
days under laboratory conditions (salinity 15, 25°C, 12L/12D, fed ad
libitum with fresh shrimp and crab meat). After this period, groups of F.
paulensis were held on different salinity (5, 10, 20 and 30 ppt) and
temperature (15, 20, 25 and 30°C combinations in 100L tanks and acclimated
for 15 days (12L/12D, fed ad libitum with fresh shrimp and crab meat).
Oxygen consumption was determined in a water flow respirometer with an
oxymeter (ORION ® - 800), for each salinity and temperature combination.
Oxygen consumption is temperature dependent in all tested salinities. On the
other hand, low salinity (5) induces high oxygen consumption only in
experiments performed below 30°C. These increases seem to be indicative of
osmotic stress. When local water conditions show signs of high temperature
and/or low salinity, the shrimp density must be reduced, to provide
sufficient oxygen amount for physiological processes of F. paulensis.
(Laboratório de Zoofisiologia –
D.C.F., Fundaçao Universidade Federal do Rio Grande, Av. Alfredo Huch, 475, CP 474, Rio Grande, RS –
Brasil, CEP 96201-900, e-mail : cabelo@octopus.furg.br)