CEREBELLAR ABIOTROPHY IN PURE-BRED ARABIA NS

Four pure-bred Arabian foals showed severe central nervous symptoms at three weeks to three months of age. The clinical diagnosis ''cerebell ar abiotrophy'' was established and later confirmed histopathologicall y in three of the cases (one foal was not available for autopsy). The dominant clinical signs consisted in severe ataxia, distinctly more pr onounced in the front legs (including rump ataxia), in dys- and extrem e hypermetric gaits and - above all - in an intention tremor of the he ad. The menace or blink reflex was absent although the vision of the f oals was probably unimpaired. The clinical signs were due to an almost total hypoplasia or atrophy of the Purkinje cell layer. The analysis of the pedigrees of the four Swiss cases, as well as of seven Belgian and one Finnish case showed that all foals were inbred to Skowronek, a stallion born in 1909 in the Ukraine and used predominantly in Englan d. All foals trace to Skowronek through his son Naseem (England, later in Russia) and/or his grandson Nana Sahib (Spain). In addition, some of the foals also trace, through Bakszysz and nor through Skowronek, t o Skowronek's grandfather Rymnik. An autosomal recessive mode of inher itance of the trait is the most likely.