Ankara Üniversitesi Veteriner Fakültesi Dergisi

Abstract

This study was based 011 hydranencephalic 22 calves.
These calves were obtained Ji'om the provinces of Antalya and İçel
during an epizootic period in ı985. The serum neutralizing antibodies
against Akabane virus were detected in eighteen blood sera tak en from
hydranencepha/ic calves and their mothers by Pirbright Animal Virus
Resem'dı Institute (A VRI) in England. Pozitive results for bluetongue
virus were also determined in eight of eighteen sera using ELISA. In
addition, the bluetongue virus was isolated Ji'om the' blood of two hydranencepha/ic calves by Etlik Animal Disease Research Institute (ADRI)
in Turkey. These isolates were identifieel as bluetongue virus serotype 4
by Pirbright AVRI. None the calves showed any remarkable clinical
symptoms except b/indness. Macroscopical/y, hemispheres were fil/ed
with various amounts of cerebrospinal fluid (CSF). The brain stems
were normal in appearance. Changes due to compression were noticed in
the thalamus. corpus striatum, hippocampus, tectum mesencephaly and
cerebel/um. The displacement and hypoplasia of the pineal body were
encountered in two different calves. Obstructioll of the third ventricle
due to precipitation of calcium salts was observed in one ca/f. The other
macroscopical findings were cystic septum pellucidum, defect of the
septum pellucidum and partial absence of the corpus cal/osum. Microscopically, narrow residual hemispheric tissues were scierotic in appearance,
although the relatively large tissues had normal histologic strııctures
and some areas of residual tissues were composed of only leptomeninges.
Generally, residual hemispheric tissues had narrow substantia a/ba protruding to the membranous sacs due to gliosis. Sclerotic appearances
were also observed in the promontorium gliosum calami scriptorU of
the medulla oblongata in almost all of the cases. The other microscopical
findings were subependymal rosettes, gliosis, subcOl.tical cavitations and
mild perivascular cujfings. Myelination was normal. These changes were
found in all cases except one, that case had nonpurulent encephalitis.