[Two rare brain malformations in black and white German Holstein calves]

Two black and white female German Holstein calves showed malformations of the cerebrum. The first calf exhibited a cystencephaly and the second calf a meningoencephalocele. The animals originated from two different dairy farms. Both calves were sired by two unrelated sires used in artificial insemination. The calf affected by cystencephaly was lacking the corpus callosum which may had been caused the cystencephaly. Exept for a pressure atrophy, the remaining parts of the brain were macroscopically and histologically inconspicious. Histological examination of the cerebrum, brain stem and cerebellum in the second calf did not reveal specific changes. A further finding in the second calf was a unilateral anophthalmia. Both animals were affected by additional defects in the spinal column including brachyuria, duplications and fusions of vertebral bodies and rips as well as malformations of the heart such as ventricular-septal defects. Only mild clinical symptoms could be observed in both calves. The calves were not inbred and further calves affected by the identical anomalies could not be ascertained at the farms where the calves were born. Chromosomal anomalies could not be detected after examination of metaphase spreads using light microscopy.