Anencephaly, bifid tongue, and cleft palate in a Pomeranian dog: GFAP and NeuN immunoreactivities

Abstract

Anencephaly is a congenital disease manifesting with the absence of the brain due to the failure of the cranial part of the neural tube to close during the embryonic stage. The disease may be accompanied by other anomalies and usually results in premature death. A stillborn puppy of a 2-year old female Pomeranian dog is examined in this case. The lack of brain tissue and accompanying abnormal skull formation was noted macroscopically. The eyes were protruding out of their normal position (protrusion), and a bifid tongue together with a secondary cleft palate was present. On serial sections stained with Haematoxylin-Eosin, only the medulla spinalis among the central nervous system structures could be inspected microscopically. Immunohistochemistry staining revealed GFAP immunoreactivity in the astrocytic glial cells. NeuN immunoreactivity was detected in the neurons in the medulla spinalis and spinal ganglions. Incomplete retinal layers were observed on the eye sections stained with Haematoxylin-Eosin and NeuN. The case was concluded to be coherent with skull and nervous system congenital malformations rarely observed in dogs. To the best of our knowledge, this represents the first description of a dog with anencephaly, bifid tongue and cleft palate.

Keywords

• anencephaly
• bifid tongue
• cleft palate
• dog
• neural tube defect

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