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Updated: Mar 21, 2026

Shifting Zebrafish Lethal Skeletal Mutant Penetrance by Progeny Testing
Published on: September 1, 2017
[Congenital and lethal semi-hairlessness in an Angler-Holstein crossbred calf]
Abstract:
A male Angler-Red Holstein crossbred calf was almost completely hairless since its birth. Hair growth was not observed within the course of its life, but with increasing age the hair structure changed from a thin and soft hair to a wiry to coarse hair fibre. Growth rate of the animal was reduced, body condition was poor but appetite was good. In addition, accompanying malformations were found including brachygnathia superior and a reduction or a particularly pronounced fine countenance skull ("shrew head"). The calf died unexpectedly at the age of five months. In the subsequent gross pathological and histopathological examination, a pronounced hyperkeratosis, degeneration of follicular epithelial cells, a reduced number of hair follicles, an increased number of telogen hair follicles, sclerosis of the corium, dilated apocrine glands and inflammatory changes of the gastrointestinal tract were seen. Based on the course of the disease, the phenotypic appearance of hypotrichosis and hair fibre as well as the histopathological changes the present case resembles a lethal semi-hairless form of hypotrichosis. This congenital anomaly in the present case is likely genetically determined.
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