Aprosopia/holoprosencephaly in a stillborn puppy: when the face predicts the brain.

In a litter of three puppies, one was stillborn and had facial and brain defects. Fusion of the maxilla and mandible and absence of the face were observed. The forebrain (telencephalon and the diencephalon) was reduced in size and fused, and the telencephalic longitudinal fissure, olfactory bulbs, and optic nerves were absent (Figures 6 and 7). Lissencephaly was observed in the telencephalon and cerebellum. A diagnosis of aprosopia/holoprosencephaly was made.