*2.12. Image Acquisition*

Fluorescent and light images were observed and analyzed with Zeiss Apotome and processed with Zeiss blue software. Digital raw images were optimized for image resolution, contrast, evenness of illumination, and background using Adobe Photoshop CC 2018 (Adobe Systems, San Jose, CA, USA). Anatomical structures were identified according to the adult *N. furzeri* brain atlas [46]. The immunoreactive cells in the rostral intestinal bulb have been counted. The cell count was carried out manually by using an open source image-processing program (ImageJ). Cells were identified on the basis of their morphological aspect.
