A stereotaxic atlas of the brain of the three-day-old domestic chick.

Preparation of a stereotaxic atlas of the brain of the 3-day-old domestic chick was prompted by the widespread use of chicks in behavioral and pharmacological research. The atlas is comprised of 26 frontal plates extending from the frontal pole to the level of the hypoglossal nucleus, and one sagittal plate at lateral 0.4 mm. Marking lesions were used to ascertain coordinates, the brains were embedded in albumin and sections cut at 36 mmu. The brain sections were stained with cresyl violet for nuclei and with hematoxylin for fibers. Unstained brain sections were used as a guide in drawing the plates to correct for shrinkage and distortion. The use of the atlas for research purposes for one year, plus test lesions targeted for specific brain structures, indicates the atlas is accurate to within 0.5 mm.