title: Spina bifida with associated malformations of the central nervous system in Dorper-cross sheep.
abstract: METHODS
  In 2008, six lambs within a flock of Dorper-cross sheep were born with musculoskeletal and neurological disease. Clinical signs included hindlimb weakness, and urinary incontinence.
  
  
  RESULTS
  All lambs had focal, inverted areas of alopecic skin over the caudal sacrum, and short, often kinked tails. Four affected lambs were subject to euthanasia, and necropsied. On gross examination, the arches of sacral vertebrae were absent, and spinal nerves and meninges were adherent to the overlying subcutis. Other gross lesions included narrow, elongated skulls, herniation of the occipital lobes into the caudal fossas, hydrocephalus, and syringomyelia. One lamb had coning of the cerebellar vermis, but cerebellar herniation through the foramen magnum was not identified.
  
  
  METHODS
  Spina bifida, with associated malformations of the central nervous system.
  
  
  CONCLUSIONS
  Examination of breeding records suggested either an autosomal recessive or partially penetrant autosomal dominant pattern of inheritance. Because of the associated tail lesions it is proposed that the pathogenesis of this syndrome involves a defect in development of the tail bud (secondary neurulation), that tethering of the spinal cord resulted in the clinical signs, and abnormal pressure of the cerebral spinal fluid resulted in the defects in the skull and brain.
authors.affiliation: Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North 4442, New Zealand. kpotter@vetmed.wsu.edu
authors.forename: K A
authors.initials: KA
authors.lastname: Potter
authors.forename: J F
authors.initials: JF
authors.lastname: Weston
authors.forename: J S
authors.initials: JS
authors.lastname: Munday
authors.forename: A C
authors.initials: AC
authors.lastname: Johnstone
mesh_terms: D000818:Animals; D001921:Brain / Q000473:pathology; D002490:Central Nervous System / Q000002:abnormalities*; D005260:Female; D020022:Genetic Predisposition to Disease; D008297:Male; D012756:Sheep; D012757:Sheep Diseases / Q000151:congenital* / Q000235:genetics / Q000473:pathology; D012886:Skull / Q000002:abnormalities; D013118:Spinal Cord Diseases / Q000151:congenital / Q000235:genetics / Q000473:pathology / Q000662:veterinary*; D016135:Spinal Dysraphism / Q000150:complications / Q000473:pathology / Q000662:veterinary*; D013623:Tail / Q000473:pathology