a shipment method for scallop seed
A.N.
Maeda-Martínez, M.T. Sicard, T. Reynoso-Granados-2000
Journal
of Shellfish Research, 19(2): 765-770
Abstract:
A “sandwich” made of layers of sponge and plywood
lids placed inside plastic bags and packed in styrofoam coolers was
evaluated as a device for shipment of catarina scallop (Argopecten
ventricosus Sowerby II, 1842) spat. Spat survival was measured to evaluate
the combined effect of temperature, emersion time, sponge thickness, spat
density, shell gapping, and O2 levels. In addition, temperature
inside the coolers with different amounts of ice was measured under
different external temperatures. Results indicate that scallop seed can
successfully be shipped out of the water over long periods of time (>37
h), taking advantage of the scallop’s capacity to breathe in air. Survival
was greatly enhanced when a pure-O2 atmosphere was
used. Highest survival was obtained at lower temperature and at shorter
emersion times. Survival was not affected by either sponge thickness or by
spat density. Higher rates of survival occurred when shells were forced to
remain tightly closed. Mortality was attributed to a combination of O2 shortage
and desiccation, but the possibility of a genotoxic effect of several
metabolites and toxicity by nitrogenous compounds as possible causes are
discussed. To maintain temperature in the coolers, 50 g L-1 of
ice was found to be optimum.
(Centro
de Investigaciones Biológicas del Noroeste S.C., P.O. Box 128, La Paz,
B.C.S. Mexico 23,000)