The mixture was
prepared by suspending 6 g of freeze dried product in 40 mL of sterile
sea water and homogenized with a sample preparation homogenizer
(Heidolph Instruments, Germany). Gill tissues were dissected immediately
after removing the animals from aquaria at intervals and preserved
for histological observations according to standard protocols
using 10% buffered formalin and 70% ethanol solutions. As with
hemocytes, gills were also used fresh, in conformity with cellular
studies. Gill tissues were sectioned through the ventral end of gill
filaments, showing their frontal surface.