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Updated: Mar 7, 2026

Quantification of Orofacial Phenotypes in Xenopus
Published on: November 6, 2014
Suspected X-linked facial dysmorphia and growth retardation in related Labrador retriever puppies
C Dierks1, H Hoffmann2, F Heinrich3
1Institute for Animal Breeding and Genetics, University of Veterinary Medicine, Bünteweg 17p, 30559 Hannover, Germany.
Abstract:
Seven male Labrador retriever puppies from four different litters were identified with a brachycephalic-like face and skull, associated with low birth weight, severe growth retardation, and reduced abilities to crawl and suckle, which were not compatible with survival. Excessive doming of the cranium, brachygnathia superior and inferior, and an abnormally opened fontanelle were found in all affected puppies by computed tomography and at post-mortem examination. Pedigree analysis supported an X-linked recessive mode of inheritance.
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