2035 biocut microtome

The EOs were subjected to anatomical examinations via light microscopy. Three F2-hybrids were fixed shortly after death by immersion in 4% formalin and the caudal peduncle was cut off. Dehydration and embedding in paraffin followed conventional techniques (Mulisch and Welsch 2010 ). The EO was sectioned serially at 4–6 µm thickness in the transverse or sagittal plane using a Leica 2035 Biocut microtome. Sections were mounted on glycerin/albumin-coated slides. Following deparaffination and rehydration, sections were stained with Azan or HE (Mulisch and Welsch 2010 ), dehydrated and coverslipped with DePeX mounting medium (Sigma-Aldrich). Sections were investigated with a Leica microscope DM4000B. Pictures were taken and processed using the Leica DFC 480 camera together with the Leica IM software version 4.0.

The EOs were subjected to anatomical examinations via light microscopy. For the preparation of the histological slides, the fish were euthanized by an overdose of ethylenglycolmonophenylether and the caudal peduncle was cut off. The tissue was fixed by immersion in 4% formalin in the case of small fish or in 10% formalin in larger fish. Fixed tissue of larger fish was decalcified with 7.5% EDTA (pH 7.4). Dehydration and embedding in paraffin followed established protocols (Mulisch and Welsch 2010 ). The EO of each specimen was sectioned serially at 4–6 µm either in the transverse or the sagittal plane using a Leica 2035 Biocut microtome. Sections were mounted on glycerin/albumin-coated slides. Following deparaffinization and rehydration, sections were stained with Azan or HE (Mulisch and Welsch 2010 ), dehydrated and coverslipped with DePeX mounting medium (Sigma-Aldrich). Sections were investigated with a Leica microscope DM4000B. Pictures were taken and processed by using the Leica DFC 480 camera together with the Leica IM software version 4.0.