Evaluation of the efficiency of fixation, decalcified and corants to study of pereiopods of Neohelice granulata (Dana, 1851)

Abstract

There were collected sixteen specimens of Neohelice granulata in the estuary of the Laguna dos Patos (Dos Patos Lagoon). From each of them, five pereiopods were collected. Two of these pereiopods were fixed in 10% Formol, other two of them in Zenker and one in Davidson, in a total of 32,32,16 repetitions respectively. After they had been fixated in Formol and Zenker they were immersed in the decalcifiers 5 % Nitric Acid and in a solution of Sodium Citrate/Formic acid. On the other hand, the appendages fixated in Davidson remained in this solution because it is a fixative/decalcified. After the material processing the glass slides were stained with the staining techniques Hematoxylin and Eosin (HE), Gomori Trichrome (TG) and Mallory Trichrome (TM). Throughout the analysis, there was determined no statistics difference between the treatments, yet it is suggested the usage of the Davidson fixative/decalcifier taking into account its handling easiness and low cost. Regarding the colorants, it was observed no difference (P>0.05) between the HE and Mallory Trichrome techniques, however they were found better than the Gomori Trichrome. The HE is the most indicated due to its price and technique easiness for the histological study with the Neohelice granulata pereiopod.