Several species of animals have a non-sex-linked, autosomal recessive cerebellar abiotrophy without apparent injury. This report describes an unusual form of cerebellar abiotrophy in two female sibling border collies. A purebred border collie produced a litter of seven puppies, five females and two males. The mother and puppies had been vaccinated against parvovirus, distemper virus, canine adenovirus 1, canine parainfluenza virus, and Bordetella bronchiseptica. The first affected puppy presented with an intention tremor, dysmetria, and wide-based stance. There was a progressive loss of menace reflex, but no loss of vision or pupillary light reflexes. The puppy was euthanized at 5 months of age. The second puppy trembled and wobbled on the pelvic limbs and progressively, over a 3-month period, fell, had difficulty climbing stairs, and exhibited head nodding. The dog was euthanized at 7 months of age. Both puppies had normal blood counts and serum biochemical analyses and negative results on serologic testing for toxoplasmosis. Only the second puppy had serologic testing for Neospora, and the results were negative. On histopathologic testing, the abnormalities were confined to the cerebelli, which were symmetrically reduced in size.
The disorder described here has been demonstrated to have a non-sex-linked, autosomal recessive mode of inheritance in other breeds of dogs. Although it has also been previously reported in border collies, too few cases have been studied to confirm the genetic mechanism in this breed, but it is suspected.
Cerebellar abiotrophy in a family of border collie dogs. Sandy JR, Slocombe RF, Mitten RW, Jedwab D. VET PATHOL 39:736-738, 2002.