Three samples were
collected at each sampling time and were fixed in
Karnovsky’s solution (Karnovsky, 1965), modified
using glutaraldehyde/paraformaldehyde (4:1, v/v)
in 0.1 M phosphate buffer (pH 7.2), during 4 h at
room temperature. Fixed material was dehydrated
in a graded ethanol series and embedded in
historesin (Leicas).