ABSTRACT
Knowledge of congenital malformations and their causes in horses is generally sparse. Such conditions require more scientific attention to improve their diagnostics and inform prevention strategies. Here, a unique syndrome of bilateral oblique facial clefts (meloschisis), rudimentary eyes and hydrocephalus is reported in an equine foetus spontaneously aborted at gestation day 224. The cause of abortion was considered to be intrauterine death caused by umbilical cord torsions and subsequent compromised blood flow, but the aetiology of the malformation could not be determined. A detailed history, which includes exposure to a range of pharmaceutical compounds during the early stages of pregnancy, is provided and emphasizes the need for accurate recording of treatments in pregnant animals.
Subject(s)
Cleft Palate/veterinary , Craniofacial Dysostosis/veterinary , Eye Abnormalities/veterinary , Horses/abnormalities , Hydrocephalus/veterinary , Maxillofacial Abnormalities/veterinary , Microphthalmos/veterinary , Abnormalities, Multiple/veterinary , Abortion, Veterinary , Animals , Female , Pregnancy , Umbilical Cord/blood supplyABSTRACT
A new recessive lethal mutation in mice that produces the otocephaly defect is described. The mutation, provisionally named oto is located on chromosome 1, within, or just outside of, a previously existing inversion, In(1)1Rk, and was probably induced by X-irradiation. The penetrance of oto is nearly complete on C57BL strain backgrounds but is reduced to a variable extent on other backgrounds. The previously reported liability to spontaneous otocephaly in the C57BL strains appears to increase the penetrance of oto. Studies of the sequences of developmental changes (conducted primarily by scanning electron microscopy) and of the range of defects indicate that a primary deficiency involving the anterior aspect of the embryonic disc occurs in affected individuals. An hypothesis related to deficiencies in mesodermal populations is presented as the basis for the craniofacial and brain defects observed.
Subject(s)
Brain/abnormalities , Chromosome Aberrations/veterinary , Chromosome Inversion , Craniofacial Dysostosis/veterinary , Genes, Lethal , Mice, Mutant Strains/genetics , Rodent Diseases/genetics , Animals , Brain/embryology , Chromosome Aberrations/embryology , Chromosome Aberrations/genetics , Chromosome Disorders , Craniofacial Dysostosis/embryology , Craniofacial Dysostosis/genetics , Ear/abnormalities , Embryo, Mammalian/ultrastructure , Female , Male , Mesoderm/ultrastructure , Mice , Mice, Mutant Strains/embryology , Rodent Diseases/embryologyABSTRACT
Mandibulofacial defects occurring in two flocks during an autumn lambing season are described. The defects were micrognathia with microtia, brachycephalus, perocephaly, bilateral oro-auricular cleft, and aprosopia. As only early lambing ewes were involved, teratogenic plant(s) were suspected as the cause.