Combined effect of
temperature and food concentration on the grazing rate of the rotifer
Brachionus plicatilis
D.J.S. Montagnes, S.A. Kimmance, G. Tsounis, J.C. Gumbs-2001
Marine Biology, 139(5): 975-979
Abstract:
We developed a predictive relationship to determine
the grazing rate of Brachionus plicatilis at given temperatures and
food concentrations; this function could be applied to experimental
culturing and aquaculture practices. Grazing experiments were conducted at
temperatures between 5°C and 40°C and at food concentrations, of the
flagellate Isochrysis galbana, ranging between ~0 and 106 ml-1.
In total, 136 grazing rates were determined, using the prey depletion
method, for rotifers acclimated to treatments for 0.5 or 4 h. The
response of grazing rate to temperature and food concentration was described
using a model that combined a rectangular hyperbolic function for food
concentration and a sigmoidal function for temperature. Using non-linear
curve-fitting methods an equation was obtained: G=(45xF)/(159000+F)x
0.94/(1+219000xT-4.35), where G is the grazing rate
(flagellates rotifer-1 min-1), F is the food
concentration (flagellates ml-1), and T is temperature (°C).
The equation indicates a maximum grazing rate of ~35 prey rotifer-1
min-1, above ~4x105 prey ml-1 and 25°C.